JP2016166865A - Spectrum measuring device, image forming apparatus, and spectrum measuring method - Google Patents

Abstract

A spectroscopic measurement apparatus, an image forming apparatus, and a spectroscopic measurement method capable of performing highly accurate colorimetric processing are provided.
A printer includes a spectroscope that receives light from a measurement target, and a carriage moving unit that relatively moves the spectroscope and the measurement target, and includes light having a first wavelength at a first time. The first measured value that is the measured value of the second and the second measured value that is the measured value of the first wavelength at the second time are compared.
[Selection] Figure 2

Description

  The present invention relates to a spectroscopic measurement apparatus, an image forming apparatus, a spectroscopic measurement method, and the like.

Conventionally, a wavelength variable interference filter capable of switching a transmission wavelength by changing a gap dimension between reflection films and a color measuring device including the wavelength variable interference filter are known (for example, see Patent Document 1). ).
In the colorimetric device disclosed in Patent Document 1, the light to be measured is irradiated with light, the light reflected by the measurement object is incident on the wavelength tunable interference filter, the light having a predetermined wavelength is transmitted through the wavelength tunable interference filter, and the detector is used. To detect. At this time, the wavelength of the transmitted light is sequentially switched by controlling the wavelength variable interference filter to sequentially change the gap size between the reflection films, and the light quantity of each wavelength is detected by the detector. Thereby, the spectral spectrum of a measuring object can be measured (colorimetry).

JP2013-238755A

By the way, there is a case where a color measuring device as described in Patent Document 1 is moved in one direction at a constant speed, for example, and color measurement of a color patch is performed during the movement. In such a case, it is necessary to acquire the light amounts of light having a plurality of wavelengths to be measured while the measurement target region by the color measurement device moves in the color patch.
However, due to changes in the speed of movement of the color measurement device and deviations in the installation position of the color patch, the measurement target area may pass through the color patch between the start of measurement and the end of measurement, or the measurement start timing may be too early. As a result, the position of the measurement range with respect to the color patch may shift. In such a case, since color measurement is performed at a position outside the color patch, accurate color measurement cannot be performed on the color patch, and the color measurement accuracy deteriorates.

  An object of the present invention is to provide a spectroscopic measurement apparatus, an image forming apparatus, and a spectroscopic measurement method capable of easily detecting a spectroscopic measurement position.

  A spectroscopic measurement apparatus according to an application example of the present invention includes a spectroscope including a wavelength variable interference filter on which light from a measurement target is incident, and a movement for relatively moving the spectroscope along one direction with respect to the measurement target. When the measurement object is a color patch, the wavelength of the light that the wavelength tunable interference filter passes is changed during a first period while the spectroscope is relatively moved in the one direction. First measurement that is a measurement value of the spectroscopic measurement at the start of measurement by performing spectroscopic measurement, passing light of the first wavelength from the wavelength variable interference filter at the start of measurement in the first period, and at the end of measurement. A value is compared with a second measurement value that is a measurement value of the spectroscopic measurement at the end of the measurement.

In this application example, the spectroscope is relatively moved along one direction with respect to the color patch to be measured, and the spectroscopic measurement is performed in the first period while the spectroscope is relatively moved. At this time, in the spectroscopic measurement device of this application example, the light emitted from the wavelength variable interference filter is set to the first wavelength at the start of measurement and at the end of measurement in the first period, and the measured value (first value) at the start of the measurement is set. Compare one measured value) with the measured value at the end of the measurement (second measured value).
That is, when the position (measurement range) where the spectroscopic measurement is performed in the first period is within the color patch region, the first measurement value and the second measurement value are the same or substantially the same. On the other hand, when the spectral measurement position at the start of measurement or at the end of measurement is out of the color patch region, the first measurement value and the second measurement value are different. Therefore, by comparing the first measurement value and the second measurement value, it is possible to easily and quickly determine whether or not the measurement range for the color patch is appropriate. Moreover, in this application example, it is not necessary to stop the spectroscope on the color patch and perform the spectroscopic measurement, and the time for spectroscopic measurement can be shortened.

In the spectroscopic measurement device of this application example, it is preferable to determine whether or not a difference between the first measurement value and the second measurement value is equal to or less than a first threshold value.
In this application example, when the difference between the first measurement value and the second measurement value is small and equal to or less than the first threshold value, it can be determined that the measurement position is on the color patch at the start of measurement and at the end of measurement. . On the other hand, when the difference between the first measurement value and the second measurement value is larger than the first threshold value, it can be determined that the measurement position by the spectroscope was not on the color patch either at the start of measurement or at the end of measurement.
In addition, the measurement values in the spectroscopic measurement rarely coincide completely due to the influence of fluctuations in the amount of light incident on the color patch, vibrations of the wavelength variable interference filter, and the like. Therefore, by appropriately setting a value that takes into account the above effects as the first threshold value, there is an error that the measurement range is shifted despite the fact that the spectroscopic measurement can be normally performed on the color patch. There is no output, and the delay of the spectroscopic measurement due to this can be suppressed.

In the spectroscopic measurement device according to this application example, the spectroscope includes a light receiving unit that receives light emitted from the variable wavelength interference filter, and an output value from the light receiving unit is used as the measurement value, and the first measurement value And comparing the second measured values.
In this application example, a light receiving unit that receives light from the variable wavelength interference filter is provided. In this case, it is possible to determine whether or not the measurement range for the color patch is appropriate using the output signal from the light receiving unit as a measurement value. Therefore, for example, it is possible to easily and quickly determine whether or not the measurement range for the color patch is appropriate as compared with the case where the calculation result such as the reflectance for the first wavelength of the color patch is used.

It is preferable that the spectroscopic measurement apparatus of this application example further includes a control unit that controls the spectroscope and the moving mechanism.
In this application example, the spectroscope and the moving mechanism can be controlled by the control unit.

In the spectroscopic measurement apparatus according to this application example, it is preferable that the control unit includes a filter control unit that changes a wavelength of light that passes through the variable wavelength interference filter.
In this application example, the wavelength of the light that the tunable interference filter passes can be controlled by the filter control means.

The spectroscopic measurement device according to this application example performs the spectroscopic measurement on the plurality of color patches along the one direction, selects the color patch whose measurement value is equal to or greater than a second threshold, and performs the selection. It is preferable to compare the first measurement value and the second measurement value of the color patch.
In this application example, the spectroscope is relatively moved with respect to a plurality of color patches arranged in one direction, and the first measurement value and the second measurement value of the color patch whose measurement value is equal to or greater than the second threshold value are compared. When the first measurement value and the second measurement value are small and less than the second threshold value, the reflectance of the color patch with respect to the first wavelength is poor and sufficient light quantity is not obtained. Cheap. In contrast, in this application example, the first measurement value and the second measurement value that are equal to or greater than the second threshold value are compared, so that the measurement range is appropriate for the color patch and is not easily affected by the noise described above. Whether or not can be determined more accurately.

  The spectroscopic measurement device of this application example determines whether or not a difference between the first measurement value and the second measurement value is equal to or less than a first threshold value, and a difference between the first measurement value and the second measurement value. Is greater than the first threshold value, the first position that is the position of the spectrometer when the first measurement value is measured and the second position that is the position of the spectrometer when the second measurement value is measured It is preferable to detect a direction in which the position is deviated from the first position and the second position when the spectroscopic measurement is performed within the region of the color patch.

In this application example, when the spectroscopic measurement apparatus determines that the measurement range of the spectroscopic measurement performed for the first period is shifted from the color patch, the spectroscopic measurement apparatus detects the shift direction.
As a result, it is possible to determine in which direction the measurement range is shifted, so in which direction the measurement range is shifted in order to appropriately set the measurement range for the color patch, i.e. It is possible to easily determine whether the measurement end time is delayed or advanced. Therefore, even when an error indicating that the measurement range is shifted is output, an error recovery process for easily recovering from the error can be performed.

  The spectroscopic measurement apparatus according to this application example is a measurement value obtained when the spectroscopic measurement is performed with the light having the first wavelength while the spectroscope is relatively moved in the one direction before the first period. A fourth measured value that is a measured value when the spectroscopic measurement is performed with the light having the first wavelength while the spectroscope is relatively moved in the one direction after the first period; It is preferable to detect the direction based on one measurement value and the second measurement value.

In this application example, the spectroscope is relatively moved in one direction with the wavelength of the light emitted from the tunable interference filter fixed at the first wavelength, and the measurement value obtained before the spectroscopic measurement for the first period is obtained. The third measurement value, the measurement value obtained after the spectroscopic measurement for the first period is acquired as the fourth measurement value. And the shift | offset | difference direction of a measurement range is detected based on a 1st measured value, a 2nd measured value, a 3rd measured value, and a 4th measured value.
Here, the position where the third measurement value and the fourth measurement value are measured is between the first measurement position and one end of the color patch when the measurement range is appropriately set for the color patch. And between the second measurement position and the other end of the color patch. In this case, if the measurement range is appropriately set in the color patch, the first measurement value, the second measurement value, the third measurement value, and the fourth measurement value are the same or substantially the same (the difference is the first threshold value). The following. On the other hand, when the measurement range is deviated, the difference between the first measurement value and the third measurement value or the difference between the second measurement value and the fourth measurement value is greater than the first threshold value depending on the direction of displacement. . Therefore, the deviation direction can be easily detected by comparing these four measured values.

The spectroscopic measurement apparatus according to this application example preferably detects the direction based on the reflectance of the surrounding color of the color patch with respect to the first wavelength, the first measurement value, and the second measurement value. .
When the reflectance for the first wavelength around the color patch is known, measurement is performed when the spectrometer is scanned in one direction with the wavelength of the light emitted from the tunable interference filter fixed at the first wavelength. It can be easily discriminated whether the value changes to a mountain shape or a valley shape by a color patch. Therefore, by comparing the magnitude relationship between the first measurement value and the second measurement value, the shift direction of the measurement range can be easily detected. For example, when the spectroscope is scanned, if the reflectance of the first wavelength is known to change in a mountain shape in the color patch, if the first measurement value is greater than the second measurement value, the measurement for the first period If it can be determined that the start time and the measurement end time are slow (the measurement range is shifted to the rear side in one direction) and the first measurement value is smaller than the second measurement value, the measurement start and measurement in the first period It can be determined that the end time is early (the measurement range is shifted to the front side in one direction). In addition, when it is known that the reflectance of the first wavelength changes in a valley shape in the color patch, when the first measurement value is larger than the second measurement value, the measurement start time and the measurement end time of the first period are early. When the first measurement value is smaller than the second measurement value, it can be determined that the measurement start and measurement end of the first period are late.

The spectroscopic measurement device of this application example determines whether or not a difference between the first measurement value and the second measurement value is equal to or less than a first threshold value, and a difference between the first measurement value and the second measurement value. Is greater than the first threshold value, the first position that is the position of the spectrometer when the first measurement value is measured and the second position that is the position of the spectrometer when the second measurement value is measured It is preferable to calculate a deviation amount that is deviated from the first position and the second position when the spectroscopic measurement is performed within the color patch region.
In this application example, when the measurement range is shifted from the color patch, the shift amount is calculated. As a result, it is possible to know the amount of movement of the measurement range for appropriately setting the measurement range for the color patch, that is, the time for changing the measurement start time and the measurement end time in the first period. Can be implemented.

At this time, it is preferable that the spectroscopic measurement apparatus according to this application example calculates the shift amount based on the first measurement value and the second measurement value with respect to two or more color patches arranged in succession. .
When the measurement range shift direction is the front side, the trigonometric function can be obtained by determining the first measurement value, the second measurement value, and the first measurement value of the color patch arranged next to the color patch. Thus, the deviation amount can be calculated. Further, when the shift direction of the measurement range is the rear side, based on the first measurement value of the predetermined color patch, the second measurement value, and the second output value of the color patch arranged in front of the color patch The amount of deviation can be calculated by a trigonometric function. That is, if the first measurement value and the second measurement value for at least two consecutive color patches are known, the shift amount can be easily calculated.

In the spectroscopic measurement apparatus of this application example, it is preferable that the moving mechanism moves the spectroscope in the one direction at a constant speed.
In this application example, the moving mechanism relatively moves the spectroscope at a constant speed, so that the position of the spectroscope at the start of measurement and the end of the measurement for the first period is separately provided with a sensor for measuring the position of the spectroscope. It can be easily detected.

A spectroscopic measurement device according to an application example of the present invention includes a spectroscope on which light from a measurement target is incident, and a moving mechanism that relatively moves the spectroscope and the measurement target. A first measurement value that is a measurement value of light of a wavelength is compared with a second measurement value that is a measurement value of light of the first wavelength at a second time.
In this application example, as described above, it is possible to easily and quickly determine whether or not the measurement range for the color patch is appropriate by comparing the first measurement value and the second measurement value.
Further, the measurement target is not limited to the color patch, and it can be determined whether or not the measurement range is appropriate for any measurement target.
In addition, the spectroscope and the measurement target are not always relatively moved during the spectroscopic measurement, and the first measurement value that is the measurement value of the light of the first wavelength at the first time and the first measurement value at the second time. By comparing the second measurement value that is the measurement value of the light of one wavelength, it is possible to determine whether or not appropriate measurement is being performed on an arbitrary measurement target.

An image forming apparatus according to an application example of the invention includes the above-described spectroscopic measurement apparatus and an image forming unit that forms an image on an image forming target.
In this application example, after the color patch as described above is formed on the image formation target by the image forming unit, the spectroscopic measurement device can perform spectroscopic measurement on the formed color patch. Further, in such an image forming apparatus, it is possible to confirm whether or not the color of the formed color patch is the same color as the color commanded to the image forming unit. Accordingly, feedback can be made to the image forming unit.

A spectroscopic measurement method according to an application example of the present invention includes a spectroscope including a wavelength variable interference filter on which light from a measurement target is incident, and a movement for moving the spectroscope relative to the measurement target in one direction. And a spectroscopic measurement method for performing spectroscopic measurement using a color patch as the measurement object, wherein the spectroscope is relatively moved in the one direction, and the spectroscope is relatively moved. During the first period, the spectroscopic measurement is performed while changing the wavelength of the light that the tunable interference filter passes, and the first wavelength from the tunable interference filter at the start of measurement and at the end of the measurement in the first period. And the first measurement value that is the measurement value of the spectroscopic measurement at the start of the measurement and the second measurement value that is the measurement value of the spectroscopic measurement at the end of the measurement are compared. To.
In this application example, the same operational effects as the above-described spectroscopic measurement apparatus can be obtained, the colorimetric range can be set at an appropriate position with respect to the color patch, and the spectroscopic measurement for the color patch can be accurately performed. Can do.

In the spectroscopic measurement method according to an application example of the present invention, the spectroscope performs spectroscopic measurement of light from the measurement target, the spectroscope and the measurement target are relatively movable, and the first wavelength light at the first time The first measured value that is the measured value of the second time and the second measured value that is the measured value of the light of the first wavelength at the second time are compared.
In this application example, as described above, it is possible to easily and quickly determine whether or not the measurement range for the color patch is appropriate by comparing the first measurement value and the second measurement value.
Further, the measurement target is not limited to the color patch, and it can be determined whether or not the measurement range is appropriate for any measurement target.
In addition, the spectroscope and the measurement target are not always relatively moved during the spectroscopic measurement, and the first measurement value that is the measurement value of the light of the first wavelength at the first time and the first measurement value at the second time. By comparing the second measurement value that is the measurement value of one wavelength, it is possible to determine whether or not appropriate measurement is being performed on an arbitrary measurement target.

1 is an external view illustrating a schematic configuration of a printer according to a first embodiment of the invention. 1 is a block diagram illustrating a schematic configuration of a printer according to a first embodiment. Sectional drawing which shows schematic structure of the spectrometer of 1st embodiment. Sectional drawing which shows schematic structure of the optical filter device of 1st embodiment. The block diagram which showed the function structure of CPU contained in the control unit in 1st embodiment. 6 is a flowchart illustrating a spectroscopic measurement method in the printer of the first embodiment. 6 is a flowchart illustrating a spectroscopic measurement method in the printer of the first embodiment. The figure which shows an example of the color chart in 1st embodiment. The figure which shows the relationship between the position of the measurement object area | region with respect to a color patch in 1st embodiment, the change of an output value, and the movement time of a carriage. The figure which shows the position of the measurement object area | region when the measurement range has not shifted | deviated with respect to the color patch in 1st embodiment, the change of an output value, and the capacitance change between reflection films. The figure which shows the position of the measurement object area | region when the measurement range has shifted | deviated with respect to the color patch in 1st embodiment, the change of an output value, and the capacitance change between reflection films. The figure which shows an example of the signal waveform of the output value at the time of the measurement range shifting in 1st embodiment. The figure which shows an example of the signal waveform of the output value at the time of the measurement range shifting in 1st embodiment. The figure which shows an example of the signal waveform of the output value at the time of the measurement range shifting in 1st embodiment. The figure which shows an example of the signal waveform of the output value at the time of the measurement range shifting in 1st embodiment. The figure which expanded a part of signal waveform of the output value at the time of a measurement range shifting in a first embodiment. The figure which expanded a part of signal waveform of the output value at the time of a measurement range shifting in a first embodiment. The figure for demonstrating the shift | offset | difference direction detection process in 2nd embodiment. The figure which shows the change of the output value with respect to the position of a reference point when a measurement range shifts | deviates. The figure which shows the change of the output value with respect to the position of a reference point when a measurement range shifts | deviates. The figure which shows the change of an output value when the area of a measurement object area | region is large. The figure which shows the measurement object area | region in 3rd embodiment.

[First embodiment]
Hereinafter, a first embodiment according to the present invention will be described with reference to the drawings. In this embodiment, as an example of the image forming apparatus of the present invention, a printer 10 (inkjet printer) including a spectroscopic measurement device will be described below.

[Schematic configuration of printer]
FIG. 1 is a diagram illustrating a configuration example of an appearance of the printer 10 according to the first embodiment. FIG. 2 is a block diagram illustrating a schematic configuration of the printer 10 according to the present embodiment.
As shown in FIG. 1, the printer 10 includes a supply unit 11, a transport unit 12, a carriage 13, a carriage moving unit 14, and a control unit 15 (see FIG. 2). The printer 10 controls the units 11, 12, 14 and the carriage 13 based on print data input from an external device 20 such as a personal computer, and prints an image on the medium A. The printer 10 of the present embodiment forms a color patch 31 for colorimetry (see FIG. 9 and the like) at a predetermined position on the medium A based on preset calibration print data, and the color patch 31. The spectroscopic measurement is performed. Accordingly, the printer 10 compares the actual measurement value for the color patch 31 with the calibration print data to determine whether or not the printed color has a color shift. If there is a color shift, the printer 10 determines the actual measurement value. Based on this, color correction is performed.
Hereinafter, each configuration of the printer 10 will be specifically described.

The supply unit 11 is a unit that supplies the medium A that is an image formation target (in this embodiment, a white paper surface is exemplified) to the image formation position. The supply unit 11 includes, for example, a roll body 111 (see FIG. 1) around which the medium A is wound, a roll drive motor (not shown), a roll drive wheel train (not shown), and the like. Then, based on a command from the control unit 15, the roll drive motor is rotationally driven, and the rotational force of the roll drive motor is transmitted to the roll body 111 via the roll drive wheel train. As a result, the roll body 111 rotates and the paper surface wound around the roll body 111 is supplied downstream (+ Y direction) in the Y direction (sub-scanning direction).
In the present embodiment, an example in which the paper surface wound around the roll body 111 is supplied is shown, but the present invention is not limited to this. For example, the medium A may be supplied by any supply method such as supplying the medium A such as a sheet of paper loaded on a tray or the like one by one with a roller or the like.

The transport unit 12 transports the medium A supplied from the supply unit 11 along the Y direction. The transport unit 12 includes a transport roller 121, a transport roller 121, a driven roller (not shown) that is driven by the transport roller 121, and a platen 122.
The conveyance roller 121 is driven by a conveyance motor (not shown), and when the conveyance motor is driven under the control of the control unit 15, the conveyance roller 121 is rotationally driven by the rotation force, and the medium A is moved between the conveyance roller 121 and the driven roller. It is transported along the Y direction while being sandwiched. A platen 122 that faces the carriage 13 is provided on the downstream side (+ Y side) of the transport roller 121 in the Y direction.

The carriage 13 includes a printing unit 16 that prints an image on the medium A, and a spectroscope 17 that performs spectroscopic measurement of a predetermined measurement target region R (see FIG. 2) on the medium A.
The carriage 13 is provided by a carriage moving unit 14 so as to be movable along a main scanning direction (one direction in the present invention, which is the X direction) crossing the Y direction.
Further, the carriage 13 is connected to the control unit 15 by a flexible circuit 131, and based on a command from the control unit 15, printing processing (image forming processing for the medium A) by the printing unit 16 and spectroscopic measurement processing by the spectroscope 17. To implement.
The detailed configuration of the carriage 13 will be described later.

The carriage moving unit 14 constitutes a moving mechanism in the present invention, and reciprocates the carriage 13 along the X direction based on a command from the control unit 15.
The carriage moving unit 14 includes, for example, a carriage guide shaft 141, a carriage motor 142, and a timing belt 143.
The carriage guide shaft 141 is disposed along the X direction, and both ends are fixed to, for example, a casing of the printer 10. The carriage motor 142 drives the timing belt 143. The timing belt 143 is supported substantially parallel to the carriage guide shaft 141, and a part of the carriage 13 is fixed. When the carriage motor 142 is driven based on a command from the control unit 15, the timing belt 143 travels forward and backward, and the carriage 13 fixed to the timing belt 143 is guided by the carriage guide shaft 141 and reciprocates.

Next, the configuration of the printing unit 16 and the spectroscope 17 provided on the carriage 13 will be described with reference to the drawings.
[Configuration of printing unit (image forming unit)]
The printing unit 16 is an image forming unit of the present invention, and forms an image on the medium A by ejecting ink onto the medium A individually at a portion facing the medium A.
The printing unit 16 is detachably mounted with ink cartridges 161 corresponding to a plurality of colors of ink, and ink is supplied from each ink cartridge 161 to an ink tank (not shown) via a tube (not shown). . Further, nozzles (not shown) for ejecting ink droplets are provided on the lower surface of the printing unit 16 (position facing the medium A) corresponding to each color. For example, piezo elements are arranged in these nozzles, and by driving the piezo elements, ink droplets supplied from the ink tank are ejected and land on the medium A to form dots.

[Configuration of spectrometer]
FIG. 3 is a cross-sectional view showing a schematic configuration of the spectrometer 17.
As shown in FIG. 3, the spectroscope 17 includes a light source unit 171, an optical filter device 172, a light receiving unit 173, and a light guide unit 174.
The spectroscope 17 irradiates illumination light onto the medium A from the light source unit 171, and causes the light component reflected by the medium A to enter the optical filter device 172 through the light guide unit 174. Then, the optical filter device 172 emits (transmits) light having a predetermined wavelength from the reflected light and causes the light receiving unit 173 to receive the light. Further, the optical filter device 172 can select a transmission wavelength based on the control of the control unit 15, and can measure the spectrum of the measurement target region R on the medium A by measuring the light amount of each wavelength of visible light. Measurement is possible.

[Configuration of light source section]
The light source unit 171 includes a light source 171A and a light collecting unit 171B. The light source unit 171 irradiates the light emitted from the light source 171 </ b> A into the measurement target region R of the medium A from the normal direction to the surface of the medium A.
The light source 171A is preferably a light source that can emit light of each wavelength in the visible light region. As such a light source 171A, for example, a halogen lamp, a xenon lamp, a white LED, and the like can be exemplified, and in particular, a white LED that can be easily installed in a limited space in the carriage 13 is preferable. The condensing unit 171B is configured by, for example, a condensing lens and condenses light from the light source 171A in the measurement target region R. In FIG. 3, the condensing unit 171B displays only one lens (condensing lens), but may be configured by combining a plurality of lenses.

[Configuration of optical filter device]
FIG. 4 is a cross-sectional view showing a schematic configuration of the optical filter device 172.
The optical filter device 172 includes a housing 6 and a wavelength variable interference filter 5 (wavelength variable interference filter) housed in the housing 6.

(Configuration of wavelength variable interference filter)
The tunable interference filter 5 is a tunable Fabry-Perot etalon element, and includes a translucent fixed substrate 51 and a movable substrate 52 as shown in FIG. By being bonded by the bonding film 53, it is configured integrally.
The fixed substrate 51 includes a first groove portion 511 formed by etching and a second groove portion 512 having a groove depth shallower than the first groove portion 511. The first groove portion 511 is provided with a fixed electrode 561, and the second groove portion 512 is provided with a fixed reflective film 54.
The fixed electrode 561 is formed in, for example, an annular shape surrounding the second groove portion 512 and faces the movable electrode 562 provided on the movable substrate 52.
The fixed reflective film 54 is, for example, a metal film such as Ag, an alloy film such as an Ag alloy, a dielectric multilayer film in which a high refractive layer and a low refractive layer are laminated, or a metal film (alloy film) and a dielectric multilayer film are laminated. It is comprised by the laminated body.

The movable substrate 52 includes a movable portion 521 and a holding portion 522 that is provided outside the movable portion 521 and holds the movable portion 521.
The movable part 521 has a thickness dimension larger than that of the holding part 522. The movable portion 521 is formed to have a diameter larger than the diameter of the outer peripheral edge of the fixed electrode 561, and the movable electrode 562 and the movable reflective film 55 are provided on the surface of the movable portion 521 facing the fixed substrate 51. ing.
The movable electrode 562 is provided at a position facing the fixed electrode 561.
The movable reflective film 55 is disposed via the gap G at a position facing the fixed reflective film 54. As the movable reflective film 55, a reflective film having the same configuration as the above-described fixed reflective film 54 can be used.

The holding part 522 is a diaphragm that surrounds the periphery of the movable part 521, and has a thickness dimension smaller than that of the movable part 521. Such a holding part 522 is easier to bend than the movable part 521, and the movable part 521 can be displaced toward the fixed substrate 51 by a slight electrostatic attraction. As a result, the gap dimension of the gap G can be changed while maintaining the parallelism of the fixed reflective film 54 and the movable reflective film 55.
In the present embodiment, the diaphragm-like holding part 522 is illustrated, but the present invention is not limited to this. For example, a configuration in which beam-like holding parts arranged at equiangular intervals around the plane center point are provided. It is good.
A plurality of electrode pads 57 individually connected to the fixed electrode 561 and the movable electrode 562 are provided on the outer peripheral portion of the movable substrate 52 (a region that does not face the fixed substrate 51).

(Case configuration)
As shown in FIG. 4, the housing 6 includes a base 61 and a glass substrate 62. The base 61 and the glass substrate 62 can use, for example, low-melting glass bonding using glass frit (low-melting glass), adhesion with an epoxy resin, or the like, thereby forming a housing space, and this housing space. A tunable interference filter 5 is accommodated therein.

The base 61 is formed by, for example, laminating ceramics on a thin plate, and has a recess 611 that can accommodate the variable wavelength interference filter 5. The wavelength variable interference filter 5 is fixed to, for example, a side surface of the concave portion 611 of the base 61 with a fixing material 64. A light passage hole 612 is provided on the bottom surface of the concave portion 611 of the base 61. The light passage hole 612 is provided so as to include a region overlapping the reflective films 54 and 55 of the wavelength variable interference filter 5. A cover glass 63 covering the light passage hole 612 is bonded to the surface of the base 61 opposite to the glass substrate 62.

  The base 61 is provided with an inner terminal portion 613 that is connected to the electrode pad 57 of the wavelength tunable interference filter 5, and the inner terminal portion 613 is provided outside the base 61 through a conduction hole 614. Connected to the outer terminal portion 615. The outer terminal portion 615 is electrically connected to the control unit 15.

[Configuration of light receiving unit and light guiding optical system]
Returning to FIG. 3, the light receiving unit 173 is disposed on the optical axis of the wavelength tunable interference filter 5 and receives light transmitted through the wavelength tunable interference filter 5. The light receiving unit 173 outputs a detection signal (current value) corresponding to the amount of received light based on the control of the control unit 15. The detection signal output by the light receiving unit 173 is input to the control unit 15 via an IV converter (not shown), an amplifier (not shown), and an AD converter (not shown).
The light guide unit 174 includes a reflecting mirror 174A and a band pass filter 174B.
The light guide unit 174 reflects the light reflected at 45 ° with respect to the surface of the medium A in the measurement target region R onto the optical axis of the wavelength variable interference filter 5 by the reflecting mirror 174A. The band-pass filter 174B transmits light in the visible light range (for example, 380 nm to 720 nm) and cuts ultraviolet light and infrared light. As a result, light in the visible light region is incident on the wavelength variable interference filter 5, and light having a wavelength selected by the wavelength variable interference filter 5 in the visible light region is received by the light receiving unit 173.

[Control unit configuration]
As shown in FIG. 2, the control unit 15 includes an I / F 151, a unit control circuit 152, a memory 153, and a CPU (Central Processing Unit) 154.
The I / F 151 inputs print data input from the external device 20 to the CPU 154.
The unit control circuit 152 includes control circuits for controlling the supply unit 11, the transport unit 12, the printing unit 16, the light source 171A, the variable wavelength interference filter 5, the light receiving unit 173, and the carriage moving unit 14, respectively. The operation of each unit is controlled based on the command signal. The control circuit of each unit may be provided separately from the control unit 15 and connected to the control unit 15.

The memory 153 stores various programs and various data for controlling the operation of the printer 10.
As various data, for example, V-λ data indicating the wavelength of light transmitted through the variable wavelength interference filter 5 with respect to the voltage applied to the electrostatic actuator 56 when controlling the variable wavelength interference filter 5, and print data For example, print profile data that stores the ejection amount of each ink with respect to the included color data. Moreover, the light emission characteristic (light emission spectrum) with respect to each wavelength of the light source 171A, the light reception characteristic (light reception sensitivity characteristic) with respect to each wavelength of the light receiving unit 173, and the like may be stored.

FIG. 5 is a block diagram illustrating a functional configuration of a CPU included in the control unit 15 of the printer 10.
The CPU 154 corresponds to the control unit of the present invention, and reads and executes various programs stored in the memory 153, thereby, as shown in FIG. It functions as filter control means 184, determination means 185, deviation amount calculation means 186, deviation direction detection means 187 (direction detection means), color measurement means 188, calibration means 189, and the like.

  The scanning control unit 181 outputs a command signal for driving the supply unit 11, the transport unit 12, and the carriage moving unit 14 to the unit control circuit 152. Accordingly, the unit control circuit 152 drives the roll drive motor of the supply unit 11 to supply the medium A to the transport unit 12. Further, the unit control circuit 152 drives the transport motor of the transport unit 12 to transport the predetermined area of the medium A along the Y direction to a position facing the carriage 13 of the platen 122. Further, the unit control circuit 152 drives the carriage motor 142 of the carriage moving unit 14 to move the carriage 13 along the X direction.

The print control unit 182 outputs a command signal for controlling the printing unit 16 to the unit control circuit 152 based on, for example, print data input from the external device 20. In the present embodiment, the print control unit 182 forms the color patch 31 on the medium A based on the calibration print data indicating that the predetermined color patch 31 of a predetermined color is formed at a predetermined position. The calibration print data may be stored in the memory 153 or may be input from the external device 20.
A detailed description of the color patch 31 will be described later.
When a command signal is output from the print control means 182 to the unit control circuit 152, the unit control circuit 152 outputs a print control signal to the printing unit 16, and drives a piezo element provided in the nozzle to the medium A. Eject ink. When printing is performed, the carriage 13 is moved along the X direction, and during the movement, a dot forming operation is performed in which ink is ejected from the printing unit 16 to form dots, and the medium A is transported in the Y direction. The conveying operation is alternately repeated to print an image composed of a plurality of dots on the medium A.

The measurement range setting means 183 sets a measurement range M (see FIG. 9) for the color patch 31, and sets a measurement start time and a measurement peripheral time for performing spectroscopic measurement for the measurement range. To do.
As described above, the color patch 31 is formed on the medium A based on the calibration print data, and the width dimension in the X direction is a predetermined dimension recorded in the calibration print data. In the present embodiment, spectral characteristics of light of a plurality of wavelengths having a predetermined interval in the visible light region (for example, light for 16 bands at intervals of 20 nm from 400 nm to 700 nm) are acquired for one color patch 31. . Therefore, it is necessary to drive the wavelength variable interference filter so that the light of the plurality of wavelengths can be acquired while the measurement target region R (see FIG. 9) moves on the one color patch 31. The measurement range setting means 183 moves the carriage 13 in the X direction (constant straight line), the filter drive time T _n necessary for switching the transmitted light of the wavelength variable interference filter 5, the number of light to be acquired (number of bands) n, The starting position M1 (see FIG. 9) and the ending position M2 (see FIG. 9) of the measurement range M within the area of the color patch 31 based on the speed v during the movement) and the size (patch width W _p ) of the color patch. Set each. Also, the time (measurement start time, measurement end time) until the predetermined reference point Rb (see FIG. 9) of the measurement target region R moves to the set start position M1 and end position M2 is calculated.

The filter control means 184 reads the drive voltage to the electrostatic actuator 56 with respect to the wavelength of the light transmitted through the wavelength variable interference filter 5 from the V-λ data of the memory 153 and outputs a command signal to the unit control circuit 152. As a result, the unit control circuit 152 applies the commanded drive voltage to the wavelength variable interference filter 5, and light having a desired transmission wavelength is transmitted from the wavelength variable interference filter 5.
Further, the filter control means 184 is based on the measurement range set by the measurement range setting means 183, the moving speed of the carriage 13 moved by the scanning control means 181 and the elapsed time from the start of the movement. The voltage applied to 56 is switched.

The determination unit 185 determines when the reference point Rb of the measurement target region R is located at the start position M1 of the measurement range M in the color patch 31 and at the end position M2 of the measurement range M in the color patch 31. Based on the measured value, it is determined whether or not the measurement range is within the area of the color patch 31 (whether or not a part of the color patch 31 is displaced from the position of the color patch 31).
In the present embodiment, an output signal (output value) from the light receiving unit 173 is used as a measurement value. Here, the output value from the light receiving unit 173 when the reference point Rb of the measurement target region R is located at the start position M1 of the measurement range M in the i-th color patch 31 is the first output value V ₁ (i) (this The first measurement value of the invention), and the output value from the light receiving unit 173 when the reference point Rb of the measurement target region R is located at the end position M2 of the measurement range M in the i-th color patch 31 is the second output value V ₂ (i) (second measurement value of the present invention) will be described hereinafter.

When the measurement range M is shifted from the color patch 31, the shift amount calculation unit 186 calculates the shift amount.
The deviation direction detection means 187 detects the deviation direction when the measurement range M is deviated from the color patch 31.
The color measurement unit 188 measures the chromaticity in the color patch 31 based on the spectroscopic measurement result for the light of a plurality of wavelengths obtained for the measurement range.
The calibration unit 189 corrects (updates) the print profile data based on the color measurement result by the color measurement unit 188 and the calibration print data.
The detailed operation of each functional configuration in the control unit 15 will be described later.

[Spectroscopic measurement method]
Next, a spectroscopic measurement method in the printer 10 of the present embodiment will be described with reference to the drawings.
6 and 7 are flowcharts showing a spectroscopic measurement method in the printer 10.
In the present embodiment, the wavelength range to be measured is a visible light range from 400 nm to 700 nm, and the initial wavelength is set to 700 nm, and the spectroscopic measurement is performed based on the light amounts of 16 wavelengths with 20 nm intervals. An example is shown.

(Formation of color chart)
In the spectroscopic measurement method using the printer 10, first, a color chart including the color patch 31 is formed on the medium A.
For this, the scanning control means 181 sets the medium A at a predetermined position (step S1). That is, the scanning control unit 181 controls the supply unit 11 and the transport unit 12 to transport the medium A in the sub-scanning direction (+ Y direction), and sets a predetermined print start position of the medium A on the platen 122. Further, the scanning control unit 181 moves the carriage 13 to the initial position (for example, the −X side end in the main scanning direction).

Thereafter, the print control means 182 reads the calibration print data from the memory 153, and prints the color chart on the medium A in synchronization with the control by the scanning control means 181 (step S2).
That is, the scanning control means 181 scans the carriage 13 to the + X side, for example, at a constant speed. The print control unit 182 identifies the position of the printing unit 16 of the carriage 13 according to the time from the start of scanning, for example, and forms dots by ejecting ink from nozzles of a predetermined color at predetermined positions based on the calibration print data. (Dot formation operation) Further, when the carriage 13 is moved to the + X side end, the scanning control unit 181 controls the supply unit 11 and the transport unit 12 to transport the medium A in the + Y direction (transport operation). Then, the scanning control unit 181 scans the carriage 13 in the −X direction, and the printing control unit 182 forms dots at predetermined positions based on the calibration print data.
A color chart is formed on the medium A by repeating the dot forming operation and the conveying operation as described above.

FIG. 8 is a diagram illustrating an example of a color chart formed in the present embodiment.
In the present embodiment, as shown in FIG. 8, a color chart in which a plurality of color patch groups 30 each including a plurality of color patches 31 arranged without gaps along the X direction are arranged along the Y direction. 3 is formed by printing. The color chart 3 includes a linear start bar 32 parallel to the Y direction on the −X side of the color patch group 30 and a linear goal bar 33 parallel to the Y direction on the + X side of the color patch group 30. Is provided. The start bar 32 and the goal bar 33 are formed in a color having a reflectance different from that of the medium A with respect to the initial wavelength. In this embodiment, the black start bar 32 and the goal bar 33 are compared with the medium A on the white paper surface. Is formed.

Furthermore, in this embodiment, when the reflectance with respect to the initial wavelength (700 nm in this embodiment) of three continuous color patches 31 is P (i−1), P (i), and P (i + 1),
P (i) -P (i-1) <0
P (i + 1) -P (i) <0
Or P (i) -P (i-1)> 0
P (i + 1) -P (i)> 0
A color patch 31 that satisfies the condition is formed based on the calibration print data. That is, in this embodiment, when the output value from the light receiving unit 173 is observed in a state where the carriage 13 is scanned along the X direction and the transmission wavelength of the wavelength variable interference filter 5 is fixed to the initial wavelength, the color patch 31 is Each time switching is performed, the output value repeatedly increases and decreases, and the output value with respect to the position of the carriage 13 (or the time after the carriage 13 moves) is an output waveform in which a peak-shaped waveform and a valley-shaped waveform appear alternately .

(Initial setting)
Returning to FIG. 6, after the ink of the printed color chart 3 is dried after step S <b> 2, the scanning control unit 181 controls the transport unit 12 to transport the medium A in the −Y direction, and the color patch. The first line 31 is positioned on the scanning straight line facing the carriage 13 (measurement target region R) (step S3).
In the following description, the color patch 31 is arranged in J rows along the Y direction, and the number of measurement target rows in the color patch 31 is indicated by a variable j (j is an integer from 1 to J). In step S <b> 3, the variable j = 1 is set, so that the scanning control unit 181 transports the medium A so that the color patch group 30 in the first row is positioned on the platen 122. In step S3, the scanning control unit 181 moves the carriage 13 to the −X side end (initial position X = 0).

After step S3, the calibration process of the spectroscope 17 is performed (step S4).
FIG. 9 is a diagram illustrating the relationship among the position of the measurement target region with respect to the color patch, the change in the output value, and the movement time of the carriage. After step S3, since the carriage 13 is positioned at the initial position of the −X side end, the measurement target region R is positioned on the −X side of the start bar 32 as shown in FIG. ing.
When a white paper surface is used as the medium A, the control unit 15 performs spectroscopic measurement on the white paper surface at the initial position. That is, the control unit 15 turns on the light source 171A, and sequentially changes the drive voltage applied to the electrostatic actuator 56 of the wavelength tunable interference filter 5 by the filter control means 184, so that the n band (20 nm interval from the initial wavelength) ( For example, the output value of the light receiving unit 173 of 16 bands is acquired. Further, the control unit 15 measures an output value (dark voltage) in a state where no light is incident on the light receiving unit 173. For this, for example, the output value from the light receiving unit 173 may be acquired in a state where the light source 171A is turned off. For example, the light guide unit 174 of the spectroscope 17 is provided with a light shielding plate that can advance and retreat with respect to the optical path. The output value from the light receiving unit 173 may be acquired after blocking the incidence of light to the light receiving unit 173 by the light shielding plate.

Then, the color measurement unit 188 performs the calibration process of the spectroscope 17 based on the spectral spectrum with respect to the white paper surface and the dark voltage. That is, in the medium A, the reference light amount (reference output value) for each wavelength when the light from the light source 171A is reflected is acquired. In the above example, when the output value for the wavelength λ when the white paper surface is measured is Vw (λ) and the dark voltage is Vd, the reference output value V _ref (λ) = Vw (λ) −Vd of the wavelength λ can be calculated. .
In the present embodiment, an example in which the medium A is a white paper surface is shown, but other colors may be used. In this case, since the color of the medium A (reflectance with respect to each wavelength) is known, the reference output value can be calculated from the output value of each wavelength during calibration. Further, when the color chart 3 is formed, a white color patch serving as a reference color may be formed on the −X side of the start bar 32. In this case, when the ink pigment has a white color, a white color patch having a known reflectance can be formed regardless of the medium A.

In step S4, calibration of the variable wavelength interference filter 5 may be performed in addition to obtaining the reference output value V _ref (λ) used at the time of spectroscopic measurement.
That is, since the light emission characteristic of the light source 171A and the light reception sensitivity characteristic of the light receiving unit 173 are known, the spectral characteristic obtained by multiplying the light emission characteristic of the light source 171A and the light reception sensitivity characteristic of the light reception unit 173, and the waveform of the output value in step S4 By comparing these, it is possible to detect a deviation between the transmission wavelength with respect to the applied voltage based on the V-λ data and the transmission wavelength with respect to the actually applied voltage. In this case, the wavelength variable interference filter 5 can be calibrated by correcting the V-λ data, for example, based on the measurement result.
In addition, a correction color patch having a reflectance or absorptance of a predetermined wavelength (for example, 700 nm which is the initial wavelength) higher than other wavelengths may be formed with respect to the initial position of the medium A. For example, when a correction color patch having only a high reflectance with respect to the initial wavelength is arranged, spectroscopic measurement is performed for each wavelength and recorded in the voltage at which the peak of the reflectance (initial wavelength) is detected and V-λ data. It is determined whether or not the voltage for the initial wavelength matches, and if the voltage is shifted, the V-λ data is corrected.

(Measurement range setting process)
After step S4, the control unit 15 sets a measurement range M for measuring each color patch 31 of the color patch group 30 of the color chart 3 (step S5).
In the following description, as shown in FIG. 9, the −X side end (minus side end) along the X direction of one color patch 31 is the first patch end 311 and the + X side end (plus side). The second patch end 312 is referred to as “end”. In the present embodiment, the first patch end 311 of the i-th color patch 31 in the color patch group 30 coincides with the second patch end 312 of the i−1th color patch 31, and the i-th color patch 31. The second patch end 312 coincides with the first patch end 311 of the (i + 1) th color patch 31. In the present embodiment, the measurement target region R is a circular spot having a diameter r (measurement width dimension r), the −X side end thereof is the first measurement region end R1, and the + X side end is the second. The measurement region end R2. In the present embodiment, the center point of the circle in the measurement target region R is set as the reference point Rb.

The color chart 3 is an image formed on the basis of the calibration print data. As shown in FIG. 9, the color chart 3 is printed from the start bar 32 to the first color patch 31 in the color chart 3 printed on the medium A. The distance W ₀ and the width dimension (patch width W _p ) along the X direction of each color patch 31 are known values.
Further, the scanning control means 181 scans the carriage 13 along the X direction with a uniform motion (speed v).
Further, after applying a driving voltage to the electrostatic actuator 56 of the wavelength tunable interference filter 5, a time (filter driving time) T _n until light having a transmission wavelength corresponding to the driving voltage is transmitted is, for example, a wavelength tunable interference filter It can be obtained by measuring in advance during the inspection. Accordingly, the time required to acquire the light amount (output value) of light for n bands is n × _Tn , and the measurement distance W _m in which the measurement target region R moves in the X direction during that period (see FIG. 9). ) Is W _m = v × (n × T _n ). In practicing actually colorimetry, while moving the measuring distance W _m, since the measurement target region R is required to fall within the region of the color patches 31, as measuring range M, at least the following formula ( It is necessary to satisfy 1).

[Equation 1]
r + W _m <W _p (1)

By the way, the position where the first patch end 311 of the color patch 31 and the first measurement region end R1 coincide (the position where the reference point Rb is + r / 2 from the first patch end 311) is the measurement range M. The position where the second patch end 312 and the second measurement region end R2 coincide with each other (the position where the reference point Rb becomes −r / 2 from the second patch end 312) is set as the start position. Assuming that the position is a position, the start position or the end position deviates from the color patch 31 only by slightly shifting the measurement range. In this case, accurate spectroscopic measurement with respect to the color patch 31 cannot be measured.
Therefore, in the present embodiment, the position on the + X side by the predetermined margin a ₁ (first distance) from the position where the first measurement region end R1 overlaps the first patch end 311 is set as the start position M1, and the second A measurement range M is set in which the position on the −X side is set to the end position M2 by a predetermined margin a ₂ (second distance) from the position where the second measurement region end R2 overlaps the patch end 312.
Therefore, the measurement range setting unit 183 sets the margins a ₁ and a ₂ and sets the measurement range M so as to satisfy the following formula (2). The margins a ₁ and a ₂ are preferably the same value. When the spectroscopic measurement is actually performed, it is impossible to predict in which direction the measurement range M will move. Therefore, by setting margins a ₁ and a ₂ having the same value on the + X side and the −X side, Reliability during measurement can be increased.

[Equation 2]
r + (a ₁ + a ₂ ) + W _m = W _p (2)

In the present embodiment, the carriage 13 is accelerated by the acceleration linear motion from the position where the initial position (X = 0) to the start bar 32, and then in the + X direction by the constant velocity linear motion at the speed v. After moving and exceeding the goal bar 33, it is decelerated by the acceleration linear motion and stopped.
Therefore, it is possible to detect the position of the measurement target region R based on the movement time when the carriage 13 is moved at a constant speed linearly at the speed v with the timing when the measurement target region R exceeds the start bar 32 as a reference position. Become. That is, in the present embodiment, the measurement range setting unit 183 sets the measurement range M as a time (measurement start time) for moving the reference point Rb of the measurement target region R to the start position M1 of each color patch 31 and the reference. The time (measurement end time) for the point Rb to move to the end position M2 of each color patch 31 is calculated. Therefore, the period from the measurement start time to the measurement end time is the first period in the present invention, and is the time when the spectroscopic measurement for the color patch 31 is actually performed.

More specifically, as shown in FIG. 9, when the wavelength transmitted from the wavelength tunable interference filter 5 is fixed (for example, the initial wavelength 700 nm), the output value from the light receiving unit 173 is the first value in the measurement target region R. The second measurement region end R2 gradually decreases after reaching the start bar 32, and when the reference point Rb passes through the center of the start bar 32, the output value becomes a minimum value, and then the output value increases again. At the timing (T = T ₀ ) when the first measurement region end R1 coincides with the + X side end of the start bar, the original output value (for example, with respect to the white paper surface) is restored. Therefore, it is possible to easily detect the reference timing T ₀ with respect to the reference position based on the waveform of the output value.
Also, the distance from the reference position to the start position M1 of the first color patch 31 is “W ₀ + a ₁ ” as shown in FIG. Accordingly, the movement time (measurement start time) T _m1 (1) from the reference timing T ₀ to the start position M 1 in the first color patch 31 is expressed by the following equation (3) and reaches the end position M 2. The travel time (measurement end time) T _m2 (1) of the following equation (4).

[Equation 3]
T _m1 (1) = (W ₀ + a ₁ ) / v (3)
T _m2 (1) = T _m1 (1) + W _m / v = (W ₀ + a ₁ + W _m ) / v (4)

Also, if the patch width _{W p} of the color patch 31 are the same, i-th starting position M1 and the end position M2 of (i ≧ 2) color patches 31 of the start position of the i-1 th color patch 31 M1 and the moved from the end position M2 patch width W _p amount corresponding color patches 31 + X-side position. Therefore, from the reference timing _{T 0,} i-th (i ≧ 2) Time to start position M1 and the end position M2 of the color patches 31 of, the following formulas (4) (5).

[ _Equation 4] T _m1 (i) = T _m1 (i−1) + W _p / v (4)
T _m2 (i) = T _m1 (i) + W _m / v
(= T _m2 (i−1) + W _p / v) (5)
(However, i ≧ 2)

When the dimensions of the color patches 31 are different, the margins a ₁ (i), a ₂ (i) for the i-th color patch 31 having the patch width W _p (i) so as to satisfy the following formula (6) ) Is set. Also in this case, it is preferable to set a ₁ (i) and a ₂ (i) to the same value.

[Equation 5]
r + (a ₁ (i) + a ₂ (i)) + W _m = W _p (i) (7)

Then, the measurement range setting means 183 uses the measurement start time T _m1 (i) and the measurement end time T _m2 (i) for the reference point Rb to move to the start position M1 and the end position M2 of the i-th color patch 31. It calculates based on following formula (8) (9).

[Equation 6]
T _m1 (i) = T _m1 (i−1) + (r + W _m + a ₂ (i−1) + a ₁ (i)) / v
(= T _m2 (i−1) + (r + a ₂ (i−1) + a ₁ (i)) / v) (8)
T _m2 (i) = T _m2 (i−1) + (r + a ₂ (i−1) + a ₁ (i) + W _m ) / v
(= T _m1 (i) + W _m / v) (9)
(However, i ≧ 2)

(Scanning measurement process)
After step S5, the following scanning measurement process is performed.
FIG. 10 is a diagram illustrating a waveform example of an output value in a state where no error has occurred.
FIG. 11 is a diagram illustrating a waveform example of an output value when an error occurs.
10 and 11, the lower row shows the position of the measurement target region R with respect to the color patch 31. The signal waveform at the middle stage indicates the waveform of the output value from the light receiving unit 173 with respect to the position of the measurement target region R. The upper signal waveform is a signal corresponding to the gap size of the reflection films 54 and 55 in the wavelength tunable interference filter 5. For example, the electric capacity when the reflection films 54 and 55 function as a capacitance detection amount electrode. It shows a change.

In the scanning measurement process, the filter control means 184 sets the voltage applied to the electrostatic actuator 56 of the variable wavelength interference filter 5 to the initial voltage with respect to the initial wavelength (for example, 700 nm) which is the first wavelength of the present invention (step S6). ).
Thereafter, the scanning control means 181 moves the carriage 13 along the X direction (step S7). In addition, the control unit 15 acquires the output value from the light receiving unit 173 at a predetermined sampling period and stores it in the memory 153. Moreover, the filter controller 184 monitors the sampled output value, to identify the reference timing T _0, and counts the elapsed time t from the reference timing T ₀ (step S8).
Then, the filter control unit 184 determines whether or not the elapsed time t from the reference timing T ₀ has reached the measurement start time T _m1 (i) set in step S5 (step S9). That is, whether or not the reference point Rb of the measurement target region R is located at the start position M1 in the measurement range M (X = X _m1 (i) (= v × T _m1 (i) or not) is determined.

If “No” is determined in step S9, the process waits until the elapsed time t reaches the measurement start time T _m1 (i).
When it determines with "Yes" in step S9, the control unit 15 performs the spectroscopic measurement with respect to the measurement range M (step S10). Specifically, the filter control unit 184 sequentially changes the voltage applied to the electrostatic actuator 56 based on the V-λ data. As a result, output values for n-band light in a predetermined wavelength region (for example, 16 output values for light having a wavelength of 20 nm intervals from 400 nm to 700 nm) are output to the control unit 15. The control unit 15 stores these output values in the memory 153 as appropriate.
Here, the filter control means 184 gradually increases the drive voltage applied to the electrostatic actuator 56 as shown in the upper signal waveforms of FIGS. The transmission wavelength is gradually shortened). Thereby, the fluctuation | variation space | interval of a gap dimension becomes small and the vibration at the time of the displacement of the movable part 521 can be suppressed. That is, it is possible to shorten the filter drive time T _n required to switch the light transmitted through the wavelength-tunable interference filter 5, to shrink measuring range M, it is possible to suppress the measurement range M deviates error from the color patches 31 it can.
In this example, an example in which the gap dimension is gradually decreased is shown, but the present invention is not limited to this. For example, the initial wavelength may be set to 400 nm (the initial voltage is set to the maximum value), and the drive voltage applied to the electrostatic actuator 56 during the spectroscopic measurement may be gradually decreased (the transmission wavelength is gradually increased).
Further, when the gap G is returned from the gap dimension corresponding to 400 nm at the end of measurement to the gap dimension corresponding to the initial wavelength 700 nm, the drive voltage may be switched stepwise. Further, the transmission wavelength may be changed from 700 nm, which is the initial wavelength, to gradually decrease from 400 nm to 40 nm at intervals of 40 nm, and then to be gradually increased from 420 nm to 680 nm at intervals of 40 nm. In such a case, when the transmission wavelength is returned to the initial wavelength after the spectroscopic measurement is completed, the sudden displacement of the movable portion 521 is suppressed. Therefore, the vibration of the movable part 521 can be suppressed more effectively, and the fluctuation of the second output value V ₂ (i) at the end position M2 can be suppressed.

Thereafter, the filter control means 184 determines whether or not the elapsed time t from the reference timing T ₀ has reached the measurement end time T _m2 (i) set in step S5 (the reference point Rb is X = X _m2 ( i) (= whether or not moved to v × T _m2 (i)) is determined (step S11).
If “No” is determined in step S11, the process waits until the elapsed time reaches the measurement end time T _m2 (i).
If it is determined as “Yes” in step S <b> 11, the filter control unit 184 returns the voltage applied to the electrostatic actuator 56 to the initial voltage, and transmits the light having the initial wavelength from the wavelength variable interference filter 5.
Note that, when the spectroscopic measurement for the n-band light is completed before the elapsed time t reaches the measurement end time T _m2 (i), the filter control unit 184 causes the electrostatic actuator 56 at the end of the spectroscopic measurement. The voltage applied to may be returned to the initial voltage.

Thereafter, the control unit 15 determines whether or not the spectroscopic measurement process for all the color patches 31 in the color patch group 30 arranged in the jth row is completed (step S12). For this purpose, the number of spectral measurement processes may be counted, and it may be determined whether or not the count has reached the total number I of color patches 31 arranged in the color patch group 30, and the carriage 13 exceeds the goal bar 33. It may be determined whether or not.
If it is determined “No” in step S12, the process returns to step S9.

(Error judgment processing)
If “Yes” is determined in step S12, the process proceeds to an error determination process shown in FIG. That is, the determination unit 185 determines whether or not the measurement range M is within the corresponding one color patch 31 based on the spectroscopic measurement result for each color patch 31 stored in the memory 153.
Specifically, the determination unit 185 refers to the spectral measurement result for each color patch 31, and receives the light at the first output value V ₁ (i) output from the light receiving unit 173 at the start position M1 and at the end position M2. The color patch 31 in which the second output value V2 (i) output from the unit 173 is equal to or greater than a predetermined second threshold is selected (step S13). As the second threshold value, for example, a value that can discriminate between a noise component and a detection signal from the light receiving unit 173 may be set.

Next, the determination unit 185 determines the absolute value (| V ₁ (i) − of the difference between the first output value V ₁ (i) and the second output value V ₂ (i) in each selected color patch 31. V2 (i) |) is calculated as an error determination value C, and it is determined whether or not there is a color patch 31 having the error determination value C equal to or greater than a predetermined first threshold value (step S14).

That is, at the start position M1 and the end position M2, the wavelength of the light transmitted through the wavelength tunable interference filter 5 is set to the same wavelength, so if the measurement range M is within the area of the color patch 31, the first As shown in FIG. 10, the output value V ₁ (i) and the second output value V ₂ (i) are the same or substantially the same, and the error determination value C that is the difference value between them should be small.
However, for example, when the movement speed or position of the carriage 13 changes due to vibration applied to the printer 10 or when the installation position of the medium A changes, as shown in FIG. The position may be shifted, and a part of the measurement range M may be off the color patch 31. In this case, the first output value V ₁ (i) and the second output value V ₂ (i) are different values, and the error determination value C is increased.
Therefore, by determining whether or not the error determination value C is equal to or greater than the first threshold value, it is determined whether or not the measurement range M is within the area of the color patch 31 (the measurement range M is within the color patch 31). Whether or not there is a positional deviation).
Note that the first threshold value may be set based on the fluctuation width of the transmission wavelength due to the vibration of the optical filter device 172 or the resonance of the movable portion 521 caused by the driving of the electrostatic actuator 56. For example, as shown in the enlarged waveform diagram in FIG. 9, the signal waveform when the output value is sampled is a waveform that vibrates with a fine amplitude. Therefore, as shown in FIG. 9, the difference α between the maximum amplitude and the minimum amplitude of fine vibrations may be set as the first threshold value.

If it is determined as “Yes” in step S14 (when there is a color patch 31 in which the error determination value C is equal to or greater than the first threshold value), the color patch 31 determined to have an error is selected in step S13. It is determined whether or not all the color patches 31 have been processed (step S15).
That is, as described above, when the measurement range M is displaced with respect to the color patch 31, the first output value V ₁ (i) and the second output value V in the spectroscopic measurement results for all the color patches 31. ₂ (i) becomes a different value, and an error should be output for all the color patches 31.
On the other hand, when the error determination value C is equal to or more than the first threshold value only in a part of the color patches 31 (when “No” is determined in step S15), for example, electrical noise or mechanical It is predicted that an error occurred accidentally due to disturbance noise caused by dynamic vibration.
In this case, for example, the determination unit 185 adds “1” to the error counter value E (initial value E = 0) stored in the memory 153 (step S16), and the error counter value E is equal to the predetermined maximum value Emax. It is determined whether or not (for example, “4”) has been exceeded (step S17).

If “No” is determined in step S17, the process returns to step S6. That is, in the case where an accidental error as described above occurs, it is determined that the error is not caused by the displacement of the measurement range, and the spectroscopic measurement is performed again.
On the other hand, if “Yes” is determined in step S17, it can be determined that there is another factor causing an error, and the forced termination process is performed (step S18). That is, even if it is determined “No” in step S15, if an accidental error occurs many times, it is considered that there are other error factors.
In the forced termination process, the scanning control unit 181 controls the supply unit 11 and the transport unit 12 to forcibly eject the medium A. In addition, it informs that an error has occurred during the spectroscopic measurement. For example, it is displayed on a display (not shown), displayed on an external device 20 such as a personal computer connected to the printer 10, or the occurrence of an error is notified by voice.

On the other hand, when it is determined as “Yes” in Step S15 (when the error determination value C is equal to or greater than the first threshold value in the spectral measurement results for all the color patches 31), the determination unit 185 determines whether an error occurs as in Step S16. “1” is added to the value E of the counter (step S19).
Then, the determination unit 185 determines whether or not the value E of the error counter has exceeded a predetermined maximum value Emax (for example, “4”) as in step S17 (step S20).
If “Yes” is determined in step S20, the process proceeds to the forced termination process in step S18.
On the other hand, if “No” is determined in step S20, the process proceeds to error recovery processing.

(Error recovery processing)
In the error recovery process, first, a deviation direction detection process is performed by the deviation direction detection means 187 (step S21).

(Deviation direction detection process)
12A, 12B, 13A, and 13B are diagrams illustrating examples of signal waveforms of output values when the measurement range M is shifted with respect to the color patch 31. FIG.
In the present embodiment, as described above, the color patch group 30 in which the reflectance with respect to the initial wavelength in the three adjacent color patches 31 is alternately increased or decreased is formed.
Therefore, when the reflectance of the i-th color patch 31 with respect to the initial wavelength is higher than that of the adjacent (i−1) th and i + 1th color patches 31, a mountain-shaped (convex) shape as shown in FIGS. 12A and 12B. A spectroscopic measurement result (change in output value) of the waveform is obtained. On the other hand, when the reflectance of the i-th color patch 31 with respect to the initial wavelength is lower than that of the adjacent (i−1) th and i + 1th color patches 31, the valley-shaped (concave) waveform as shown in FIGS. 13A and 13B. The spectroscopic measurement result is obtained.
In step S21, the deviation direction detection unit 187 first determines whether the output value change for the i-th color patch 31 is a mountain shape (convex shape) or a valley shape (concave shape) based on the calibration print data. Determine whether. That is, since each color patch 31 is formed based on the calibration print data, the reflectance with respect to the initial wavelength for the i-th color patch 31 is higher or lower than that for the (i−1) th and i + 1th color patches 31. This can be easily determined based on the calibration print data.

Although the above illustrates that the relationship of the reflectance of each color patch is stored in the calibration print data, the present invention is not limited to this.
For example, as shown in FIGS. 12A and 13A, the second output value V ₂ (i−1) for the i−1th color patch 31, the first output value V ₁ (i) for the ith color patch 31, Based on the second output value V ₂ (i) for the i-th color patch 31 and the first output value V ₁ (i + 1) for the i + 1-th color patch 31, the output value change is mountain-shaped or valley-shaped. You may determine whether there is.
Specifically, when the conditions of the following formulas (10) to (12) are satisfied, the deviation direction detection unit 187 determines that the output value change is a mountain shape (convex shape).

[Equation 7]
V ₁ (i)> V ₂ (i-1) (10)
V ₁ (i)> V ₁ (i + 1) (11)
V ₂ (i)> V ₁ (i + 1) (12)

  Moreover, when satisfy | filling the conditions of following formula (13)-(15), the shift | offset | difference direction detection means 187 determines with an output value change being a trough type (concave type).

[Equation 8]
V ₁ (i) <V ₂ (i-1) (13)
V ₂ (i) <V ₂ (i-1) (14)
V ₂ (i) <V ₁ (i + 1) (15)

Then, as shown in FIG. 12A, the output value change is a mountain shape, and the relationship between the first output value V ₁ (i) and the second output value V ₂ (i) for the i-th color patch 31 is , V ₁ (i)> V ₂ (i), the deviation direction detection means 187 determines that the position deviation direction is the + X side (measurement start time is too late).
Also, as shown in FIG. 12B, the change in the output value is a mountain shape, and the relationship between the first output value V ₁ (i) and the second output value V ₂ (i) is V ₁ (i) <V _2. In the case of (i), the deviation direction detection unit 187 determines that the direction of the deviation is on the −X side (measurement start time is too early).

On the other hand, as shown in FIG. 13A, the change in the output value is valley-shaped, and the relationship between the first output value V ₁ (i) and the second output value V ₂ (i) for the i-th color patch 31 is , V ₁ (i) <V ₂ (i), the deviation direction detection means 187 determines that the direction of the deviation is the + X side (measurement start time is too late).
Further, as shown in FIG. 13B, the output value change is valley-shaped, and the relationship between the first output value V ₁ (i) and the second output value V ₂ (i) is V ₁ (i)> V _2. In the case of (i), the deviation direction detection unit 187 determines that the direction of the deviation is on the −X side (measurement start time is too early).

(Deviation amount calculation process)
After step S21, the deviation amount calculation means 186 calculates the deviation amount of the measurement range M with respect to the color patch 31 (step S22).
Hereinafter, an example of a calculation method of the deviation amount by the deviation amount calculation unit 186 will be described.
14A and 14B are enlarged views of a part of the waveform of the output value when an error is detected. FIG. 14A shows the case where the measurement range M is shifted to the −X side, and FIG. 14B shows the measurement range. Is a signal waveform when is shifted to the + X side.
When the measurement target region R moves to another adjacent color patch 31 with the transmission wavelength of the tunable interference filter 5 set to the initial wavelength, the area of the measurement target region R is sufficiently small and the moving speed of the carriage 13 If v is fast, the output value from the light receiving unit 173 changes substantially linearly.
The distance along the X direction of the linear portion B is the width dimension (diameter r) of the measurement target region R when the measurement range M is within the region of the color patch 31. However, when the measurement range M is displaced and does not fall within the area of the color patch 31, the distance along the X direction of the linear portion B is shortened.
Therefore, when the measurement range M is shifted to the −X side, as shown in FIG. 14A, the distance L from the point P1 at which the distance along the X direction of the linear portion B becomes the diameter r to the start position M1 is This is the amount of movement necessary to fit the measurement range M within the color patch 31 area. When the measurement range M is deviated to the + X side, as shown in FIG. 14B, the distance L from the point P2 where the distance along the X direction of the linear part B becomes the diameter r to the end position M2 is This is the amount of movement required to fit the measurement range M within the color patch 31 area.

Here, when the measurement range M is shifted to the −X side, the inclination β of the linear part B is, as shown in FIG. 14A, the error determination value C and the i-th first output value V ₁ (i ) And the absolute value D ₁ (= | (V ₁ (i) −V ₂ (i−1) |)) of the difference between the i−1th second output value V ₂ (i−1) and β = It can be calculated as (C + D ₁ ) / r.
When the measurement range M is shifted to the + X side, as shown in FIG. 14B, the error determination value C, the i-th second output value V ₂ (i), and the i + 1-th first output value V ₁ (i + 1) can be calculated as β = (C + D ₂ ) / r using the absolute value D ₂ (= | (V ₂ (i) −V ₁ (i + 1) |) of the difference.
That is, the inclination β of the linear part B can be calculated based on the output values of the start position M1 and the end position M2 for the two color patches 31 adjacent to each other.

When the measurement range M is deviated to the −X side, the moving distance L required to fit the measurement range M within the area of the color patch 31 is determined by the inclination β of the linear portion B and the error determination value C. Used, L = C / β. Further, if the start position M1 is moved to the + X side by the distance L, a margin is not ensured. Therefore, the start range M1 is moved to the + X side by L + a ₁ (= x _C1 ) in consideration of the margin, so that the measurement range M Is moved to the position to be originally set.
That is, when the measurement range M is shifted to the −X side, the shift amount calculation unit 186 outputs the output values V ₁ (i), V ₂ (i), V ₂ (i−1) and the measurement target region R. a diameter r, the margin _{a 1,} on the basis, calculates the shift amount _{x C1.}

On the other hand, even when the measurement range M is deviated to the + X side, the moving distance L required to fit the measurement range M within the area of the color patch 31 includes the inclination β of the linear portion B and the error determination value C. Used, L = C / β. In this case, in consideration of the margin _{a 2,} the end position _{M2 L + a 2 (= x} C2) by moving only the -X side, the measuring range M is moved to the position to be originally set. That is, when the measurement range M is shifted to the + X side, the shift amount calculation unit 186 outputs the output values V ₁ (i), V ₂ (i), V ₁ (i + 1) and the diameter r of the measurement target region R. When a margin _{a 2,} on the basis, calculates the shift amount _{x C2.}

(Measurement range correction)
After the deviation direction detection process in step S21 and the deviation amount calculation process in step S22, the measurement range setting means 183, based on the deviation direction detected in step S21 and the deviation amount calculated in step S22, The position of the measurement range M, the measurement start time T _m1 (i), and the measurement end time T _m2 (i) are corrected (step S23).
Specifically, when the deviation direction is on the −X side, the measurement range setting unit 183 means that the measurement start time is early, and therefore delays the measurement start time by x _C1 / v.
Further, when the deviation direction is on the + X side, it means that the measurement start time is late, so that the measurement start time is advanced by x _C2 / v.
That is, the measurement range setting means 183 starts measurement as shown in the following formulas (16) to (19), where T _M1 (i) is the previously set measurement start time and T _M2 (i) is the measurement end time. The time T _m1 (i) and the measurement end time T _m2 (i) are corrected.

[Equation 9]
(When the displacement direction is -X side)
T _m1 (i) = T _M1 (i) + x _C1 / v (16)
T _m2 (i) = T _M2 (i) + x _C1 / v (17)
(When the displacement direction is + X side)
T _m1 (i) = T _M1 (i) −x _C2 / v (18)
T _m2 (i) = T _M2 (i) −x _C2 / v (19)

Thereafter, the process returns to step S6, and the scanning measurement process is performed again based on the set new measurement start time T _m1 (i) and the measurement end time T _m2 (i).

(Line feed processing)
In step S14, it is determined as “No”, and it is determined that the error determination value C is equal to or less than the first threshold (no error) for all the color patches 31 in the color patch group 30 in the j-th row of the color chart 3. In this case, the scanning control means 181 adds “1” to the variable j (step S24), and determines whether or not the variable j is equal to or greater than the maximum value J corresponding to the last row of the color patch group 30 (step S24). Step S25).
If “No” is determined in step S25, the scanning control unit 181 transports the medium A so that the color patch group 30 in the j-th row is positioned on the platen 122 (step S26). Thereafter, the process returns to step S6. In the case where the patch width W _p for each color patch 31 is different for each color patch group 30, after step S26, the process returns to step S5, sets the measurement range M.

(Colorimetry processing and profile update processing)
When it is determined as “Yes” in step S25 (when the spectroscopic measurement process is completed for all the color patches 31 in the color chart 3 without error), the scanning control unit 181 controls the transport unit 12 to discharge the paper. The operation is performed to eject the medium A (step S27).

Thereafter, the color measuring unit 188 determines the wavelength for each wavelength of the color patch based on the output value of each wavelength acquired for each color patch and the reference output value V _ref (λ) obtained in step S4. The reflectance is calculated (step S28). That is, the color measurement unit 188 performs color measurement processing for each color patch and calculates chromaticity.
Thereafter, the calibration unit 189 updates the print profile data stored in the memory 153 based on the chromaticity of each color patch recorded in the calibration print data and the chromaticity calculated in step S28. (Step S29).

[Operational effects of this embodiment]
In the present embodiment, the carriage moving unit 14 moves the carriage 13 including the spectroscope 17 having the wavelength variable interference filter 5 in the X direction, so that the spectroscope is applied to the color patch 31 provided on the medium A. 17 measurement object regions R are moved along the X direction.
At this time, the control unit 15 changes the wavelength of light transmitted from the wavelength variable interference filter 5 according to the position of the measurement target region R with respect to the set measurement range M by the filter control means 184. That is, the filter controller 184 scans the carriage 13 in the X direction, and starts the measurement when the reference point Rb of the measurement target region R is located at the start position M1 of the measurement range M, and the reference point Rb is located at the end position M2. At the end of the measurement, an initial voltage is applied to the electrostatic actuator 56 of the variable wavelength interference filter 5 to set the transmission wavelength to the initial wavelength. Further, the filter control means 184 applies a voltage to be applied to the electrostatic actuator 56 while the reference point Rb of the measurement target region R moves within the measurement range M from the start position M1 to the end position M2 (first period). The transmission wavelength is sequentially changed by sequentially switching.
The determination unit 185 receives the first output value V ₁ (i) from the light receiving unit 173 when the measurement target region R is located at the start position M1, and the light reception when the measurement target region R is located at the end position M2. The second output value V ₂ (i) from the unit 173 is compared.
In this way, by comparing the first output value V ₁ (i) and the second output value V ₂ (i), whether or not the measurement range M is set at an appropriate position with respect to the color patch 31 is determined. Can be easily determined. In addition, since the spectroscopic measurement with respect to the measurement range M can be performed with the carriage 13 moved, for example, the spectroscopic measurement can be performed more quickly than when the carriage 13 is stopped on the color patch 31 and the spectroscopic measurement is performed. Can be implemented.

Further, since the first output value V ₁ (i) and the second output value V ₂ (i) from the light receiving unit 173 are compared, for example, the reflectance (V for the first wavelength calculated by the colorimetric unit 188) Compared to the case of using ₁ (i) / V _ref (λ)), the processing is easier and it is possible to quickly determine whether or not the measurement range M is appropriate.

  Further, the color measurement unit 188 outputs when the measurement target region R moves within the measurement range M when it is determined that the measurement range M is within the region of the color patch 31 according to the determination result. Color measurement processing for the color patch 31 is performed based on each output value. For this reason, the color measurement based on the spectral measurement result in the area of the color patch 31 can be performed with high accuracy.

In the present embodiment, the determination unit 185 determines that the absolute value (error determination value C) of the difference between the first output value V ₁ (i) and the second output value V ₂ (i) is equal to or less than the first threshold value. Then, it is determined that the measurement range M is located within the area of the color patch 31. Accordingly, the determination unit 185 can easily determine whether or not the measurement range M is set to an appropriate position only by comparing the error determination value C with the first threshold value. Further, since the output value from the light receiving unit 173 is output in a minute vibration waveform due to electric noise or noise due to mechanical vibration, the first threshold value is set to a value α in consideration of the noise or the like. Thus, for example, it is possible to prevent erroneous detection of an error as compared with the case where it is determined whether or not the difference between the first output value V ₁ (i) and the second output value V ₂ (i) is “0”. And the processing efficiency can be improved.

In the present embodiment, the determination unit 185 has a first output value V ₁ (i) and a second output value V ₂ (i) that are equal to or greater than the second threshold among the plurality of color patches 31 arranged along the X direction. The color patch 31 is selected, and the displacement of the measurement range M is determined based on the first output value V ₁ (i) and the second output value V ₂ (i) of the selected color patch 31.
Thereby, it is possible to omit the output value of the low signal level that is easily affected by noise, and to accurately determine the displacement of the measurement range M based on the output value of the high signal level that is not easily affected by noise.

In the present embodiment, the first patch edge 311 of the color patches 31, to set the starting position M1 to the position of r / 2 + _{a 1} only the + X side, the second patch edge 312, r / ₂ + _a 2 by -X side Is set to the end position M2. That is, immediately before the measurement target region R, the margin a ₁ provided during a period from completely contained within the area of the color patches 31 to the starting position M1, out of the color patches 31 measurement area R from the end position M2 margin a ₂ is provided between the up.
By providing such margins a ₁ and a ₂ , for example, even when the position of the measurement range M with respect to the color patch 31 is slightly shifted due to mechanical vibration or the like, the shift within the margins a ₁ and a ₂ is reduced. In some cases, no error is output, normal spectroscopic measurement for the color patch 31 can be performed, and color measurement processing for each color patch 31 by the color measurement unit 188 can be performed with high accuracy.

In the present embodiment, when the determination unit 185 determines that the measurement range M is displaced with respect to the color patch 31, the displacement direction detection unit 187 that detects the direction of the displacement is provided. Accordingly, in which direction the previously set measurement range M should be moved, that is, the measurement start time T _m1 (i) and the measurement end time T _m2 (i) may be advanced or delayed. Can be easily determined. Therefore, the measurement range setting unit 183 can easily reset the position of the measurement range M, and can quickly perform error recovery processing.

In the present embodiment, the deviation direction detection unit 187 acquires the reflectance with respect to the initial wavelength of the i-th color patch 31 and the i−1th and i + 1th color patches 31 adjacent to the i-th color patch 31 before and after the i-th color patch 31. And the direction of misalignment is detected based on the first output value V ₁ (i) and the second output value V ₂ (i).
That is, the deviation direction detection unit 187 moves the carriage 13 in the X direction in a state where the wavelength of the light transmitted through the wavelength variable interference filter 5 is fixed to the initial wavelength based on the reflectance of the color patch 31 and surrounding colors with respect to the initial wavelength. It can be determined whether the output value at the time of scanning is a peak waveform or a valley waveform. And if it is a mountain-shaped waveform and V ₁ (i)> V ₂ (i), the misalignment direction is + X side, and if V ₁ (i) <V ₂ (i), the misalignment direction is −X. If it is a valley waveform, and V ₁ (i)> V ₂ (i), the displacement direction is −X side, and V ₁ (i) <V ₂ (i). It can be determined that the positional deviation direction is the + X side. That is, if the signal waveform of the output value can be discriminated, the deviation direction detection means 187 uses the first output value V ₁ (i) and the second output value V ₂ (i) for judging the positional deviation of the measurement range M. Thus, the misalignment direction can be easily detected.

In this embodiment, the displacement amount calculation unit 186 calculates the displacement amount of the measurement range M with respect to the color patch 31.
As a result, when the measurement range M is reset by the measurement range setting means 183, the amount to which the measurement range M should be moved is calculated. Based on this, the measurement range M is reset to an appropriate position. (Correction).

In the present embodiment, when the measurement range M is displaced to the + X side, the deviation amount calculation unit 186 has the measurement width dimension r, the first output value V ₁ (i), and the second output value V ₂ (i). The deviation amount is calculated based on the first output value V ₁ (i + 1). When the measurement range M is displaced to the −X side, the measurement width dimension r, the first output value V ₁ (i), the second output value V ₂ (i), and the second output value V ₂ (i The deviation amount is calculated based on -1).
That is, the deviation amount calculation unit 186 can easily perform the deviation based on the first output value V ₁ (i) and the second output value V ₂ (i) for determining the positional deviation of the measurement range M of each color patch 31. The amount of deviation can be calculated.

In the present embodiment, the measurement range setting means 183 includes the measurement start time T _m1 (i) until the measurement target region R moves to the start position M1 when the carriage 13 is linearly moved at a constant speed, and the measurement target region. The measurement end time T _m2 (i) until R moves to the end position M2 is calculated.
In this case, the position of the carriage 13 can be specified using the internal timer of the control unit 15, and for example, the configuration can be simplified and downsized as compared with the case where the position of the carriage 13 is detected by a position sensor or a distance sensor.

  In the present embodiment, as described above, high-precision color measurement processing is performed on the color patch 31 based on the spectral measurement result acquired when the measurement range M is within the area of the color patch 31. Therefore, the calibration unit 189 can appropriately update the print profile data based on the color measurement result. That is, based on the difference between the chromaticity of each color patch printed by the printing unit 16 based on the calibration print data and the chromaticity of each color patch based on the actually measured high-precision color measurement result, By providing feedback to the printing unit 16, appropriate color correction can be performed, and the color desired by the user can be reproduced with high accuracy.

[Second Embodiment]
Next, a second embodiment according to the present invention will be described. In the following description, the same configurations and the same processes as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.
In the first embodiment described above, in the plurality of color patches 31 arranged continuously in the X direction, the reflectance with respect to the initial wavelength alternately increases and decreases (the waveform of the output value becomes a peak shape or a valley shape). Indicated. On the other hand, the second embodiment is different from the first embodiment in that the direction of displacement of the measurement range M can be detected even when the change in reflectance with respect to the initial wavelength of the arranged color patches 31 is unknown. To do.

That is, when the reflectance change of the color patch 31 arranged in the X direction is unknown, the waveform of the output value is a mountain-shaped signal waveform as shown in FIGS. 12A and 12B, or as shown in FIGS. 13A and 13B. In addition to the valley-shaped signal waveform, the output value may monotonously increase or monotonously decrease. In such a case, if the reflectance change with respect to the initial wavelength of each color patch is not recorded as the calibration print data, the method of the first embodiment can detect the direction of displacement of the measurement range M. It becomes difficult.
On the other hand, in the second embodiment, the deviation direction detection means 187 detects the direction of the deviation of the measurement range M by the following method.

FIG. 15 is a diagram for explaining the deviation direction detection processing of the second embodiment.
In this embodiment, in the shift direction detection processing in step S21 using light of the initial wavelength, in addition to the first output value V ₁ (i) and the second output value V ₂ (i) for the i-th color patch, Three output values V ₃ (i) (third measured value of the present invention) and fourth output value V ₄ (i) (fourth measured value of the present invention) are obtained, and based on these output values, the deviation direction Is detected.
The third output value V ₃ (i) is an output value output from the light receiving unit 173 when the measurement target region R is located at a predetermined pre-start position M3 before the start position.
As the pre-start position M3, when the entire measurement target region R exceeds the first patch end 311 and reaches the start position M1 when the measurement range M is set to a normal position. Is set to That is, the position on the −X side by the distance a ₃ (third distance) smaller than the margin a ₁ than the start position M ₁ is set as the pre-start position M 3.
Further, as the post-end position M4, when the measurement range M is set to a normal position, the entire measurement target region R is between the end position M2 and before reaching the second patch end 312. Is set. That is, the position of the small distance a _{4 (fourth} distance) by + X side of the margin a ₂ than the end position M2 and after the end position M4.

Therefore, the measurement range setting means 183 sets T _m3 (i) = T _m1 (i) −a ₃ / v as the pre-measurement start time T _m3 (i) corresponding to the pre-start position M3, and the post-end position T _m4 (i) = T _m2 (i) + a ₄ / v is set as the time T _m4 (i) after the measurement corresponding to M4.

FIGS. 16A and 16B are diagrams showing changes in the output value with respect to the position of the reference point Rb when the measurement range M is displaced in the second embodiment. FIG. 16A shows the measurement range M on the −X side. 16B shows a case where the measurement range (M) is shifted to the + X side.
In the present embodiment, as shown in FIG. 16A, the deviation direction detection means 187 has an absolute value of the difference between the first output value V ₁ (i) and the third output value V ₃ (i) larger than the first threshold value. When the absolute value of the difference between the second output value V ₂ (i) and the fourth output value V ₄ (i) is equal to or smaller than the first threshold value, the measurement range M is shifted to the −X side. judge.
Further, as shown in FIG. 16B, the deviation direction detection means 187 has an absolute value of a difference between the first output value V ₁ (i) and the third output value V ₃ (i) equal to or less than the first threshold value. When the absolute value of the difference between the two output values V ₂ (i) and the fourth output value V ₄ (i) is larger than the first threshold value, it is determined that the measurement range M is displaced to the + X side.

In the present embodiment, the third output value V ₃ (i) and the fourth output value for the pre-start position M3 and the post-end position M4 even if the magnitude relationship of the reflectance with respect to the initial wavelength of the adjacent color patch 31 is unknown. V ₄ (i) is acquired, the relationship between the first output value V ₁ (i) and the third output value V ₃ (i), the second output value V ₂ (i) and the fourth output value V ₄ (i ), It is possible to easily determine the direction of displacement.

[Third embodiment]
Next, a third embodiment according to the present invention will be described.
In the first embodiment and the second embodiment described above, an example in which the measurement target region R is a circular spot having a diameter r has been shown. However, in the third embodiment, each of the above-described points is that the measurement target region R is a rectangular spot. It is different from the embodiment.

In each of the above embodiments, it is assumed that when the measurement target region R exceeds the end portions 311 and 312 of the color patch 31, the output value changes to a substantially linear shape. Even in this case, when the area of the measurement target region R is sufficiently small and the speed v of the carriage 13 is sufficiently high, a measurement error that affects the spectroscopic measurement process does not occur.
However, for example, when a spectral image of the color patch 31 is acquired and chromaticity measurement is performed in consideration of color unevenness of the color patch, a measurement target region having a relatively large area (a predetermined third threshold value or more). The R light is received by a light receiving unit 173 configured by an image sensor such as a CCD sensor.
In this case, the change in the output value is as shown in FIG.
FIG. 17 is a diagram illustrating a change in the output value when the spectroscope 17 performs the spectroscopic measurement process on the color patch 31 when the diameter of the measurement target region R that is a circular spot is large.

As shown in FIG. 17, when the measurement target region R is a circular spot and the area thereof is large, when the measurement target region R moves to the adjacent color patch 31, the center point (reference point) of the measurement target region R A waveform of an output value curved in a cubic curve is obtained with the output value when Rb) is positioned on the end of the color patch 31 as an inflection point.
In this case, as in the first embodiment, when the slope β (= (C + D ₁ ) / r) is calculated and the distance L is calculated as L = C / β, from the point P1 to be originally calculated to the start position M1. The distance to the point P3 before (−X side) from the point P1 is calculated instead of the distance, and a slight error occurs.

FIG. 18 is a diagram illustrating the measurement target region Q in the present embodiment.
Measurement target region Q in the present embodiment has a measurement patch width W _p along the X direction, two parallel sides along the X direction, rectangular with two sides parallel to the Y direction orthogonal to X direction It becomes a shape.
When the measurement target region Q having such a shape is used, even when the measurement target region Q has a large area, the measurement target region Q is moved to the adjacent color patch 31 across the end portions 311 and 312 of the color patch 31. The change waveform of the output value has a linear shape similar to that of the first embodiment. Therefore, the deviation amount can be calculated with high accuracy by the same method as in the first embodiment described above.

The configuration for setting the measurement target region Q of the rectangular measurement spot is, for example, in the spectroscope 17, in the light guide 174, the glass substrate 62 or the cover glass 63 of the optical filter device 172, the optical filter device 172, and the like. A rectangular aperture is provided between the light receiving portions 173, on the light incident surface of the light receiving portion 173, the surfaces of the substrates 51 and 52 of the wavelength variable interference filter 5, and the like. As a result, only the light in the rectangular measurement target region Q that has passed through the aperture in the incident light is received by the light receiving unit 173. Alternatively, a rectangular reflecting mirror 174A may be used, and a black frame may be provided on the outer periphery of the reflecting mirror 174A, for example.

[Modifications] The present invention is not limited to the above-described embodiments, and the configuration obtained by appropriately combining the modifications, improvements, and the like within a range in which the object of the present invention can be achieved. It is included in the invention.

(Modification 1)
In each of the above embodiments, the carriage moving unit 14 that moves the carriage 13 in the + X direction is illustrated as the moving mechanism of the present invention, but the present invention is not limited to this.
For example, the carriage 13 may be fixed and the medium A may be moved with respect to the carriage 13. In this case, the vibration of the variable wavelength interference filter 5 accompanying the movement of the carriage 13 can be suppressed, and the transmission wavelength of the variable wavelength interference filter 5 can be stabilized.
Moreover, although the example which scans the measurement object area | region R along an X direction with respect to the color patch 31 arrange | positioned along the X direction was shown, the measurement object area | region R is moved to a Y direction with respect to the color patch 31. You may scan along. In this case, the measurement target region R can be moved relative to the color patch 31 by sending the medium A in the Y direction by the transport unit 12. In this case, since one direction (scanning direction) in the present invention is the Y direction, the measurement range setting unit 183 sets the measurement range M with respect to the color patch 31 along the Y direction. That is, the measurement start time and the measurement end time for each color patch 31 may be set based on the paper feed speed v by the transport unit 12.

(Modification 2)
In each of the above embodiments, the color patch group 30 in which a plurality of color patches 31 are arranged adjacent to each other in the X direction is illustrated, but a configuration in which a gap is provided between the color patches 31 may be employed. In this case, when the medium A is a white paper surface, when the transmitted light from the wavelength variable interference filter 5 is fixed to the initial wavelength and the carriage 13 is scanned in the X direction, the signal waveform of the output value in the color patch 31 is a mountain shape. It becomes a waveform. Further, when the medium A is a black paper surface or when a black frame is arranged between the color patches 31, the signal waveform of the output value in the color patch 31 is a valley waveform. Therefore, even if the reflectance with respect to the initial wavelength of each color patch 31 is unknown, the position shift direction can be easily detected by the method of the first embodiment.
Furthermore, in the color chart 3, an example in which a plurality of color patches 31 are arranged is shown. However, for example, only a single color patch 31 may be arranged, and color measurement processing may be performed on the color patch 31. .

(Modification 3)
In each of the above embodiments, an example in which the spectroscopic measurement process is performed on each color patch 31 while the carriage 13 is moved to the + X side has been described. However, each color patch 31 is moved while the carriage 13 is moved to the −X side. Spectral measurement processing may be performed.
Further, spectroscopic measurement processing is performed on the odd-numbered color patch group 30 arranged in the color chart 3 while the carriage 13 is moved to the + X side. The spectroscopic measurement process may be performed while the carriage 13 is moved to the −X side.
In this case, the color chart 3 are line-symmetrical shape with respect to parallel imaginary lines and street Y direction center of the movement range of the carriage 13, when the patch width W _p of the color patch are the same, the carriage the measurement start time _T m1 (i) and the measurement end time _T m2 times for (i) in the case of moving 13 to the + X side, the measurement start time _T m1 (i) and in the case of moving the carriage 13 on the -X side It can be applied as the measurement end time T _m2 (i). When the patch widths W _{p of the} color patches in the color patch groups 30 in the color chart 3 are different or are not line-symmetric with respect to the virtual line, the measurement target region R is measured from the goal bar 33. Is set to the measurement start time T _m1 (i) and the measurement end time T _m2 (i), respectively.

(Modification 4)
In each of the above embodiments, in step S13, the color patch 31 in which the first output value V ₁ (i) and the second output value V ₂ (i) are equal to or greater than the second threshold value is selected, and the selected color patch 31 is selected. Although the positional deviation determination of the measurement range M was performed based on the output value, the present invention is not limited to this. For example, based on the first output value V ₁ (i) and the second output value V ₂ (i) in all the color patches 31, the misregistration determination of the measurement range M may be performed.

(Modification 5)
In each of the above embodiments, the margins a ₁ and a ₂ are set when setting the measurement range M, but the present invention is not limited to this.
For example, the measurement range setting unit 183 may set the measurement range M without providing a margin. In this case, the start position M1 is a position where the first patch end 311 and the first measurement region end R1 overlap (immediately after the measurement target region R enters the region of the color patch 31), and the end position M2 is This is the position where the second patch end 312 and the second measurement region end R2 overlap (immediately before the measurement target region R comes out of the color patch 31). When such a measurement range M is set, the measurement distance W _m can be set wide, the time for detecting light of one wavelength can be lengthened, and the vibration of the movable part 521 when the wavelength tunable interference filter 5 is driven. It is possible to acquire the amount of transmitted light in a surely stationary state. Therefore, when there is no positional deviation of the measurement range M, it is possible to perform a highly accurate spectroscopic measurement process, thereby improving the accuracy of the spectroscopic measurement process for the color patch 31.
Further, in the case of measuring the distance W _m is fixed (the number of bands n and filter drive time T _n is fixed), it is also possible to shorten the patch width W _p of the color patch 31, one row color patches More color patches 31 can be arranged in the group 30.

(Modification 6)
In each of the embodiments described above, the measurement range setting means 183 includes the patch width W _p of the color patch 31, the diameter r of the measurement target region R, the number n of measurement bands in the measurement range M, and the filter drive required for one spectroscopic measurement. After setting the margins a ₁ and a ₂ based on the time T _n , the measurement start time T _m1 (i) and the measurement end time T _m2 (i) for the start position M1 and the end position M2 are set. It is not limited.
For example, margins a ₁ and a ₂ may be set in advance for the color patch 31.
Further, the carriage 13 is scanned in a state where the transmitted light of the wavelength tunable interference filter 5 is fixed to the initial wavelength, and the patch width W _p of the color patch 31 is calculated based on the waveform of the output value from the light receiving unit 173. The margins a ₁ and a ₂ may be set based on the patch width W _p thus set.
Furthermore, in this case, whether or not the calculated patch width W _p has a sufficient dimension for setting sufficient margins a ₁ and a ₂ that are equal to or larger than a predetermined value, and n-band spectroscopic measurement. If the measurement distance W _m of the measurement range M for performing the measurement is determined to be a sufficient dimension, and it is determined that the margin dimension and the measurement distance W _m are insufficient, the measurement range M in the measurement range M The number of color measurements (number of bands n) may be decreased.

(Modification 7)
In the above embodiment, the measurement range setting unit 183 uses the position where the measurement target region R exceeds the start bar 32 as a reference position, and is required for the measurement target region R to move from the reference position to the start position M1 and the end position M2. Although time was set as the measurement start time and the measurement end time, respectively, it is not limited to this.
For example, the measurement start time and measurement end time of the measurement range M with respect to each color patch 31 from the initial position may be set with the carriage 13 positioned at the extreme end on the -X side (initial position) as the reference position. Good.

(Modification 8)
The measurement start time and the measurement end time for each color patch 31 are based on the timing when the entire measurement target region R exceeds the second patch end 312 of the color patch 31 arranged in the previous stage. An end time may be set.
That is, when the carriage 13 is scanned along the X direction with the light transmitted through the wavelength tunable interference filter 5 fixed to the initial wavelength, the measurement target region R straddles the end 311 (312) of the color patch 31. When moving, the signal waveform of the output value changes into a substantially linear shape, and the output value becomes substantially constant when the measurement target region R completely enters the region of the color patch 31. Therefore, the timing at which the output value becomes constant may be detected, and the start position M1 and the end position M2 may be determined based on the elapsed time from this timing.
In this case, the measurement range setting means 183 sets the measurement start time T _m1 as T _m1 = a ₁ / v because the position where the measurement target region R has advanced by the margin a ₁ is the start position. Also, the measurement end time T _m2 is calculated as T _m2 = T _m1 + W _m / v, where the width dimension of the measurement range M is W _m .
When such measurement start time and measurement end time are set, the measurement range M does not shift in all of the plurality of color patches 31. Therefore, if remeasurement is performed on a part of the color patches 31 in which an error has been detected, the spectroscopic measurement results for all the color patches 31 can be easily obtained, and the measurement time can be shortened.

(Modification 9)
In the embodiment described above, the deviation amount and the deviation direction when the measurement range M is displaced are obtained by the deviation amount calculation unit 186 and the deviation direction detection unit 187. However, the present invention is not limited to this.
For example, when it is determined that the measurement range M does not fall within the area of the color patch 31, the measurement range setting unit 183 causes the measurement range M to be changed by a minute amount in a predetermined direction and is reset, and spectroscopic measurement is performed again. Then, by repeating this, the measurement range M may be set to an appropriate position.

  Further, only the deviation amount calculation unit 186 may be provided, and the deviation direction detection unit 187 may not be provided. In this case, when it is determined that the measurement range M does not fall within the area of the color patch 31, the measurement range setting unit 183 moves the measurement range M to, for example, the + X side by a correction amount corresponding to the shift amount, and again. Perform spectroscopic measurements. When it is determined that the measurement range M is displaced again, the measurement range setting unit 183 moves the measurement range M to the −X side, for example, by a correction amount corresponding to the displacement amount. Thereby, even when the misalignment direction is unknown, the measurement range M can be set to an appropriate position.

  Further, the shift amount calculation unit 186 may not be provided, and only the shift direction detection unit 187 may be provided. In this case, when it is determined that the measurement range M does not fall within the area of the color patch 31, the measurement range M is set to a minute amount (for example, margin a1) on the side opposite to the displacement direction detected by the measurement range setting unit 183. , A2), and the spectral measurement is performed again. When it is determined that the measurement range M is displaced again, the measurement range M is moved again by a minute amount. By repeating this, the measurement range M can be set to an appropriate position even when the amount of displacement is not known.

(Modification 10)
In the above embodiment, the measurement range setting unit 183 calculates the measurement start time and the measurement end time from the reference position, but is not limited to this.
For example, the position of the carriage 13 (the position of the measurement target region R) in the X direction may be detected based on the position sensor and the rotation angle and the number of rotations of the drive motor of the carriage moving unit 14. In this case, the measurement range setting unit 183 sets the start position M1 and the end position M2 for each color patch 31, and the filter control unit 184 applies a voltage to the electrostatic actuator 56 based on the detected position. May be controlled.

(Modification 11)
In each of the above embodiments, the determination unit 185 determines whether or not the measurement range M is appropriate based on the output value from the light receiving unit 173. For example, the reflectance (based on the spectroscopic measurement) Based on V ₁ (i) / V _ref (λ), V ₂ (i) / V _ref (λ)), it may be determined whether or not the measurement range M is appropriate.

(Modification 12)
In each of the above embodiments, the filter control unit 184 has set the initial wavelength as the first wavelength of the present invention at the start of measurement and at the end of measurement for the measurement range M. However, the present invention is not limited to this.
For example, at the start of measurement and at the end of measurement, a predetermined first wavelength (for example, 400 nm) different from the initial wavelength in the measurement range M may be set. In this case, the set first wavelength is similarly set in the time from the measurement end time T _m2 (i) for the i-th color patch 31 to the measurement start time T _m1 (i + 1) for the i + 1-th color patch 31. Set.
In each of the above embodiments, an example in which the initial drive voltage is applied and the initial wavelength is set at the start of measurement and at the end of measurement has been described. The wavelength of light that passes through the variable interference filter 5 may be set as the first wavelength.

(Modification 13)
In the control unit 15, the configuration in which the unit control circuit 152 is provided is illustrated. However, as described above, each control unit may be provided separately from the control unit 15 and provided in each unit. For example, the spectroscope 17 may be provided with a filter control circuit for controlling the wavelength variable interference filter 5 and a light receiving control circuit for controlling the light receiving unit 173. Further, the spectroscope 17 may include a microcomputer and a storage memory storing V-λ data, and the microcomputer may function as the filter control unit 184, the determination unit 185, and the color measurement unit 188.

(Modification 14)
As the printing unit 16, the ink jet type printing unit 16 that discharges the ink supplied from the ink tank by driving the piezoelectric element is illustrated, but the printing unit 16 is not limited thereto. For example, the printing unit 16 may have a configuration in which bubbles are generated in the ink by a heater to discharge the ink, or a configuration in which the ink is discharged by an ultrasonic transducer.
Further, the present invention is not limited to the ink jet type, and can be applied to any printing type printer such as a thermal printer using a thermal transfer method, a laser printer, or a dot impact printer.

(Modification 15)
As the spectroscope 17, the configuration example in which the light of the light source unit 171 is irradiated from the normal direction to the medium A and the light reflected by the medium A at 45 ° is incident on the wavelength variable interference filter 5 by the light guide unit 174 is shown. However, it is not limited to this.
For example, light may be incident on the surface of the medium A at an angle of 45 °, and light reflected in the normal direction of the medium A may be received by the light receiving unit 173 via the wavelength variable interference filter 5. .
Further, although the light that reflects the medium A at 45 ° is received by the light receiving unit 173 via the wavelength variable interference filter 5, the light reflected at other than 45 °, such as 30 °, may be received. That is, the angles of the optical axes of the light receiving unit 173 and the wavelength variable interference filter 5 may be set so that the light regularly reflected by the medium A is not received by the light receiving unit 173.

(Modification 16)
In each of the embodiments described above, for convenience of explanation, the color patch 31 is provided in the section where the carriage 13 performs the constant linear motion, and the measurement start time T _m1 (i) and the measurement end time T _m2 (i) are set. It is not limited to this.
For example, the color patch 31 may be provided near the initial position on the medium A. That is, the color patch 31 may be arranged in a section where acceleration motion is performed from the initial position. In this case, the measurement range setting means measures the measurement start time T _m1 (i) and the measurement end time T _m2 (i) for the color patch 31 for the period in which the carriage 13 performs the acceleration motion and the constant speed motion, respectively. Set.
Furthermore, even when the carriage 13 does not perform a constant velocity linear motion even after the start bar 32 is exceeded, and the speed of the carriage 13 changes in a predetermined speed pattern, the measurement range M is determined based on the speed pattern. The measurement start time T _m1 (i) and the measurement end time T _m2 (i) may be obtained.

(Modification 17)
In the third embodiment, when the area of the measurement target region R is large, a configuration in which an aperture is provided in the spectroscope 17 so that the measurement target region R is rectangular, or a configuration in which the reflecting mirror 174A is rectangular. However, the present invention is not limited to this.
For example, based on a signal change in the output value from the light receiving unit 173 (curved part B ′ in FIG. 17) when the measurement target region R straddles the end portions 311 and 312 of the color patch 31, the curve is approximated to a polynomial. Then, the shift amount (distance L + margin a ₁ from point M1 to point P1) may be calculated based on the approximated polynomial.

(Modification 18)
Further, as the wavelength variable interference filter 5, the light transmission type wavelength variable interference filter 5 that transmits light having a wavelength corresponding to the gap G between the reflection films 54 and 55 from the incident light is illustrated, but the wavelength variable interference filter 5 is not limited thereto. For example, a light reflection type tunable interference filter that reflects light having a wavelength corresponding to the gap G between the reflection films 54 and 55 may be used. Other types of variable wavelength interference filters may be used.

(Modification 19)
Further, the optical filter device 172 in which the wavelength tunable interference filter 5 is housed in the housing 6 is illustrated, but a configuration in which the wavelength tunable interference filter 5 is directly provided in the spectroscope 17 may be employed.

(Modification 20)
Furthermore, although the optical filter device 172 provided with the wavelength variable interference filter 5 illustrated the configuration (post-spectroscopy) provided between the light guide unit 174 and the light receiving unit 173, it is not limited to this.
For example, the wavelength variable interference filter 5 or the optical filter device 172 including the wavelength variable interference filter 5 is disposed in the light source unit 171, and the medium A is irradiated with light dispersed by the wavelength variable interference filter 5 (front Spectroscopy).

(Modification 21)
In each said embodiment, although the printer 10 provided with the spectrometer was illustrated, it is not limited to this. For example, a spectroscopic measurement apparatus that does not include an image forming unit and performs only color measurement processing on the medium A may be used. For example, the spectroscopic measurement apparatus of the present invention may be incorporated into a quality inspection apparatus that performs quality inspection of printed matter manufactured in a factory or the like, and the spectroscopic measurement apparatus of the present invention may be incorporated into any other apparatus.

(Modification 22)
The measurement target is not limited to the color patch, and may be any substance.
For example, the present invention can be applied to a spectroscope that detects foreign substances in food moving on a belt conveyor. When detecting an organic substance as a foreign substance, it is preferable to use a spectroscope that performs spectroscopy of near-infrared light to mid-infrared light.

(Modification 23)
In each of the above embodiments, the carriage moving unit 14 that moves the carriage 13 along one direction (X direction) is exemplified as the moving mechanism of the present invention, but the present invention is not limited to this.
For example, the carriage moving unit 14 may be configured to be able to move the carriage 13 along the X direction and the Y direction. Alternatively, the carriage 13 may be fixed and the medium A may be moved along the X direction and the Y direction with respect to the carriage 13.
Moreover, the said structure may be employ | adopted and the measurement object area | region R may be moved to the arbitrary directions along XY plane. In other words, the measurement target and the measurement target region R may be configured to be relatively movable in any direction along the XY plane. For example, the measurement target region R may be scanned along a curved line along the XY plane, or the scanning direction may be changed during measurement. Thereby, it is possible to perform spectroscopic measurement at a plurality of positions not on a straight line while scanning the measurement target region R.
Furthermore, the measurement target region R and the measurement target may be relatively moved in a three-dimensional manner, whereby spectroscopic measurement can be performed even when the surface of the measurement target is a curved surface.

(Modification 24)
Of course, the present invention may be applied while the measurement target and the spectroscope are relatively moving, but when the measurement target and the spectroscope are not relatively moving, or the measurement target and the spectroscope are The present invention can be applied when the relative movement is intermittently performed.
For example, the first measurement value measured at the first time and the second measurement value measured at the second time are obtained from the same position of the measurement object, or the measurement object and the spectroscope are relative to each other. It is also within the scope of the present invention to obtain the second measurement value in a state where the object to be measured and the spectroscope are moving relative to each other.
Specifically, for example, even if the moving mechanism is stopped, the relative position between the spectroscope and the measurement target may change due to some reason such as a user unexpectedly touching the measurement target. Even in such a case, whether or not the measurement range for the measurement target is appropriate can be determined easily and quickly by comparing the first measurement value and the second measurement value obtained at different times as in the above embodiments. It is possible to determine whether or not a displacement of the measurement range with respect to the measurement object has occurred.

(Modification 25)
In each of the above-described embodiments, the configuration in which the spectroscope 17 includes the wavelength variable interference filter 5 as a spectroscopic element capable of changing the spectroscopic wavelength when the light from the measurement target is spectroscopically illustrated, but is not limited thereto. For example, the spectroscope 17 includes various spectroscopic elements capable of changing spectral wavelengths such as AOTF (acousto-optic tunable filter), LCTF (liquid crystal tunable filter), and grating instead of the wavelength variable interference filter 5. Also good.
Moreover, although the spectroscope 17 illustrated the structure containing the spectroscopic element which can change a spectroscopic wavelength, for example, spectroscopic wavelengths, such as an interference filter with which the gap dimension between the reflecting films 54 and 55 was fixed, are predetermined one wavelength. It is also possible to include a spectroscopic element. Even in such a case, by comparing the first measurement value measured at the first time with the second measurement value measured at the second time for the same wavelength to be measured, it is easy and quick. It can be determined whether or not the measurement range for the measurement object is appropriate.

  In addition, the specific structure for carrying out the present invention may be configured by appropriately combining the above-described embodiments and modifications within the scope that can achieve the object of the present invention, and may be appropriately changed to other structures and the like. May be.

DESCRIPTION OF SYMBOLS 5 ... Wavelength variable interference filter (wavelength variable interference filter), 10 ... Printer (image forming apparatus), 12 ... Conveyance unit, 13 ... Carriage, 14 ... Carriage movement unit (movement mechanism), 15 ... Control unit, 16 ... Printing part (Image forming unit), 17 ... spectrometer, 30 ... color patch group, 31 ... color patch, 32 ... start bar, 33 ... goal bar, 54 ... fixed reflective film, 55 ... movable reflective film, 56 ... electrostatic actuator, 171 ... Light source unit, 171A ... Light source, 171B ... Condensing unit, 172 ... Optical filter device, 173 ... Light receiving unit, 174 ... Light guide unit, 174A ... Reflective mirror, 174B ... Band pass filter, 181 ... Scanning control means, 182 ... print control means, 183 ... measurement range setting means, 184 ... filter control means, 185 ... determination means, 186 ... deviation Calculation means, 187 ... deviation direction detection means, 188 ... spectroscopic measurement means, 189 ... calibration means, 311 ... first patch end, 312 ... second patch end, A ... medium, B ... linear part, C ... error Determination value, G ... gap, M ... measurement range, M1 ... start position, M2 ... end position, M3 ... position before start, M4 ... post-end position, Q ... measurement area, R ... measurement area, R1 ... first measurement region ends, R2 ... second measuring area end portion, Rb ... reference point, T 0 _... reference _{timing, T m1} (i) ... measurement start _{time, T m2} (i) ... measurement end _{time, T} m3 (i) ... Time before measurement start, T _m4 (i) ... Time after measurement, Tn ... Filter drive time, V ₁ (i) ... First output value (first measurement value), V ₂ (i) ... Second output value (Second measured value), V ₃ (i) ... third output value (third measured value), V ₄ (I) ... fourth output value (fourth measurement value), W _m ... measurement distance, W _p ... patch width, a ₁ ... margin, a ₂ ... margin, r ... diameter dimension (measurement width dimension).

Claims (16)

A spectroscope on which light from a measurement object is incident;
A moving mechanism for relatively moving the spectroscope and the measurement object;
Including
Spectroscopy characterized by comparing a first measurement value that is a measurement value of light of a first wavelength at a first time with a second measurement value that is a measurement value of light of the first wavelength at a second time measuring device. A spectroscope including a tunable interference filter on which light from a measurement object is incident;
A moving mechanism that relatively moves the spectroscope along one direction with respect to the measurement object,
When the measurement target is a color patch, in the first period while the spectroscope is relatively moved in the one direction, the spectroscopic measurement is performed while changing the wavelength of the light that the wavelength variable interference filter passes, First measurement value, which is a measurement value of the spectroscopic measurement at the start of measurement, is passed through the wavelength variable interference filter at the start of measurement and at the end of measurement in the first period, and the measurement is completed. A spectroscopic measurement device that compares a second measurement value that is a measurement value of the spectroscopic measurement at the time. The spectrometer according to claim 2,
It is determined whether a difference between the first measurement value and the second measurement value is equal to or less than a first threshold value. In the spectroscopic measurement device according to claim 2 or 3,
The spectrometer includes a light receiving unit that receives light emitted from the wavelength variable interference filter,
The first measurement value and the second measurement value are compared using the output value from the light receiving unit as the measurement value. In the spectroscopic measurement device according to any one of claims 2 to 4,
The spectroscopic measurement apparatus further comprising a controller that controls the spectroscope and the moving mechanism. The spectrometer according to claim 5, wherein
The said control part contains the filter control means which changes the wavelength of the light which passes the said wavelength variable interference filter. The spectrometry apparatus characterized by the above-mentioned. The spectrometer according to any one of claims 2 to 6,
The spectroscopic measurement is performed on the plurality of color patches along the one direction, the color patch whose measured value is equal to or greater than a second threshold value is selected, and the first of the selected color patches is selected. A spectroscopic measurement device that compares a measured value and the second measured value. The spectroscopic measurement apparatus according to any one of claims 2 to 7,
If the difference between the first measurement value and the second measurement value is less than or equal to a first threshold value, and the difference between the first measurement value and the second measurement value is greater than the first threshold value, The first position that is the position of the spectrometer when the first measurement value is measured and the second position that is the position of the spectrometer when the second measurement value is measured are areas of the color patch. The direction which has shifted compared with the 1st position and the 2nd position at the time of performing the spectroscopic measurement in the inside is detected. The spectroscopic measurement device characterized by things. The spectrometer according to claim 8, wherein
Before the first period, a third measurement value that is a measurement value when the spectroscopic measurement is performed with the light of the first wavelength while the spectroscope is relatively moved in the one direction, and the first period Later, a fourth measurement value that is a measurement value when the spectroscopic measurement is performed with the light of the first wavelength while the spectroscope is relatively moved in the one direction, the first measurement value, and the second measurement The said direction is detected based on a value. The spectroscopic measurement apparatus characterized by the above-mentioned. The spectrometer according to claim 8, wherein
The spectroscopic measurement device that detects the direction based on a reflectance of the surrounding color of the color patch with respect to the first wavelength, the first measurement value, and the second measurement value. The spectrometer according to any one of claims 2 to 10,
If the difference between the first measurement value and the second measurement value is less than or equal to a first threshold value, and the difference between the first measurement value and the second measurement value is greater than the first threshold value, The first position that is the position of the spectrometer when the first measurement value is measured and the second position that is the position of the spectrometer when the second measurement value is measured are areas of the color patch. A shift amount that is shifted compared to the first position and the second position when the spectroscopic measurement is performed is calculated. The spectrometer according to claim 11, wherein
The spectroscopic measurement apparatus, wherein the shift amount is calculated based on the first measurement value and the second measurement value with respect to two or more color patches arranged in succession. The spectrometer according to any one of claims 2 to 12,
The movement mechanism moves the spectroscope in the one direction at a constant speed. The spectroscopic measurement device according to any one of claims 2 to 13,
An image forming apparatus comprising: an image forming unit that forms an image on an image forming target. The spectroscope measures the light from the object to be measured,
The spectroscope and the measurement object are relatively movable,
Spectroscopy characterized by comparing a first measurement value that is a measurement value of light of a first wavelength at a first time with a second measurement value that is a measurement value of light of the first wavelength at a second time Measuring method. A color patch using a spectroscopic measurement device including a spectroscope including a wavelength tunable interference filter on which light from the measurement target is incident, and a moving mechanism that relatively moves the spectroscope along one direction with respect to the measurement target. Is a spectroscopic measurement method for performing spectroscopic measurement with the measurement object,
Relatively moving the spectrometer in the one direction;
During the first period while the spectroscope is relatively moved, spectroscopic measurement is performed while changing the wavelength of the light that the tunable interference filter passes,
At the start of measurement in the first period, and at the end of measurement, pass the light of the first wavelength from the wavelength variable interference filter,
A first measurement value that is a measurement value of the spectroscopic measurement at the start of the measurement and a second measurement value that is a measurement value of the spectroscopic measurement at the end of the measurement are compared.