JP2019109374A - Optical module, spectrometry device, spectrometry method, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical module for accurately detecting the intensity of light with respect to a wavelength of light. SOLUTION: A fixed reflective film 11 that passes through a part of incident light 3 and reflects a part thereof, and a fixed reflective film 11 that is arranged to face the fixed reflective film 11 and passes through a part of the incident light 3 and reflects a part of the incident light 3. The space changing unit 39 and the reflecting unit are such that the movable reflecting film 13 is caused by natural vibration of the fixed reflecting film 11 and the movable reflecting film 13 to change the distance 15 between the reflecting portions between the fixed reflecting film 11 and the movable reflecting film 13. The interval detection unit 29 that detects the distance 15, the light receiving element 24 that receives the light 3 passing through the fixed reflective film 11 and the movable reflective film 13 and detects the intensity of the light 3, the fixed reflective film 11 and the movable reflective film. A calculation unit 53 for calculating the relationship between the wavelength of the light 3 passing through 13 and the intensity of the light 3 is provided, and when the second integer is an integer larger than the first integer, the calculation unit 53 is the distance between the reflection units. The intensity of the first light 70, in which 15 is a half wavelength of the light 3, and the intensity of the second light 71, in which the distance 15 between the reflecting portions is twice the half wavelength of the light, are used. [Selection diagram] Fig. 1

Description

  The present invention relates to an optical module, a spectrometer, a spectrometer method, and an electronic device.

  Patent Document 1 discloses an optical module provided with a variable wavelength interference filter capable of switching the wavelength of passing light by changing the distance between the reflecting portions between the first reflecting portion and the second reflecting portion. There is. According to this, the spectrometry apparatus causes the light reflected by the measurement object to be incident on the variable wavelength interference filter, and detects the light of the predetermined wavelength that has passed through the variable wavelength interference filter. The variable wavelength interference filter comprises a first reflecting portion and a second reflecting portion facing each other. And the wavelength of the light which passes a wavelength variable interference filter can be switched by changing the distance between reflection parts between a 1st reflection part and a 2nd reflection part, and the intensity of the passage light of each wavelength can be detected. Thereby, the spectrum of the measurement object can be measured.

  In this spectrometer, after adjusting the distance between the reflection parts of the variable wavelength interference filter to a desired value, the passing light is detected. However, in order to maintain the distance between the reflection portions at a desired value, it is necessary to apply a high drive voltage to the variable wavelength interference filter. For this reason, the power consumption in the spectrometer has been increased.

  As a method of reducing power consumption, a method of resonating one of the first reflecting portion and the second reflecting portion and vibrating it by natural vibration can be considered. In this method, stable vibration can be performed with a small force. Then, the optical module detects the distance between the reflecting portions and the intensity of light passing through the variable wavelength interference filter a plurality of times within one cycle.

  An integral multiple of half wavelengths of light passing through the variable wavelength interference filter is a distance between the reflection portions. By limiting the light passing through the variable wavelength interference filter with a band pass filter or the like, the relationship between the light wavelength and the intensity can be detected. Therefore, the optical module using natural vibration can detect the light spectrum by suppressing the power consumption.

JP, 2013-238755, A

  The variable wavelength interference filter is vibrated by natural vibration. Then, charge can be accumulated between the first reflecting portion and the second reflecting portion, and the distance between the reflecting portions can be estimated by detecting the voltage between the first reflecting portion and the second reflecting portion. . When the variable wavelength interference filter is subjected to the natural oscillation, there are a place where the voltage between the first reflection part and the second reflection part changes rapidly within one cycle and a place where the voltage changes late. In the place of the timing where voltage changes rapidly, since the dispersion | variation in the measured value of distance between reflection parts becomes large, estimation accuracy falls. Therefore, an optical module that accurately detects the intensity of light with respect to the wavelength of light has been desired.

  The present invention has been made to solve the above-described problems, and can be realized as the following modes or application examples.

Application Example 1
In an optical module according to the application example, a first reflecting portion that passes a part of incident light and reflects a part, and a portion of the incident light that is disposed to face the first reflecting portion. Between the reflecting portions which is the distance between the first reflecting portion and the second reflecting portion by causing the second reflecting portion, which passes and reflects a part, to inherently vibrate the first reflecting portion and the second reflecting portion An interval changing unit that changes a distance, an interval detecting unit that detects the distance between the reflecting units, and a light receiving element that receives light passing through the first reflecting unit and the second reflecting unit to detect the intensity of the light An arithmetic operation unit for calculating the relationship between the wavelength of light passing through the first reflection unit and the second reflection unit and the intensity of the light, and the second integer is an integer larger than the first integer, The calculating unit is configured to calculate the intensity of the first light whose distance between the reflecting portions is the first integer multiple of the half wavelength of light, and between the reflecting portions. Away is characterized the intensity of the second light is the second integer multiple of the half wavelength of the light, the use of.

  According to this application example, the optical module includes the first reflecting portion and the second reflecting portion. The first reflecting portion and the second reflecting portion are disposed to face each other. The first reflecting portion and the second reflecting portion respectively transmit a part of incident light and reflect a part. The first reflecting portion and the second reflecting portion are disposed at a predetermined interval, and the interval changing portion changes the distance between the first reflecting portion and the second reflecting portion. The distance between the first reflecting portion and the second reflecting portion is taken as the distance between the reflecting portions. The interval detection unit detects the distance between the reflection units.

  Light in which the distance between the reflecting portions is equal to an integral multiple of a half wavelength passes through the first reflecting portion and the second reflecting portion. Let the second integer be an integer greater than the first integer. Then, light in which the distance between the reflecting portions is a first integer multiple of a half wavelength of light is taken as a first light, and light in which the distance between the reflecting portions is a second integer multiple of a half wavelength of light is taken as second light. The light passing through the first reflecting portion and the second reflecting portion includes the first light and the second light.

  The light receiving element receives the light passing through the first reflecting portion and the second reflecting portion to detect the intensity of the light. The calculation unit uses the intensity of the first light and the intensity of the second light. As for the intensity of light passing through the first reflecting portion and the second reflecting portion, the first light is detected stronger than the second light. It is presumed that this difference in intensity is due to the difference in the distance of light traveling between the reflecting portions. That is, since the distance between the reflecting portions is shorter in the first light than in the second light, it is presumed that the intensity of the light is not easily attenuated while traveling between the reflecting portions. The light with high intensity can measure the intensity more accurately than the light with low intensity. Therefore, the first light can measure the light intensity more accurately than the second light.

  The first reflector and the second reflector are caused to vibrate inherently, and the distance changer changes the distance between the reflectors. At the timing when the distance between the reflective portions changes, there is a timing when the speed at which the distance between the reflective portions changes changes is fast and the timing when the speed is slow. And, since the change of the wavelength of the passing light is fast in the part where the change speed of the distance between the reflection parts is fast, the variation of the measured value becomes large. Since the change of the wavelength of the passing light is slow at a place where the change speed of the distance between the reflection portions is slow, the variation of the measured value becomes small.

  The first light and the second light in the light having the same wavelength are different in the distance between the reflecting portions. For this reason, the change speed of the distance between reflecting portions may be different between the first light and the second light in the light having the same wavelength. Therefore, in the first light, when the change speed of the distance between the reflection parts is fast, the calculation part calculates the light intensity by calculating the light intensity using the second light where the change speed of the distance between the reflection parts is slow. It can be calculated well. As a result, the optical module can accurately output the light intensity with respect to the light wavelength.

Application Example 2
In the optical module according to the application example, the calculation unit uses the second light to calculate the intensity of light having a wavelength of 400 nm or more and less than 480 nm, and the calculation unit performs the calculation of the intensity of light having a wavelength of 480 nm or more and less than 700 nm. The relationship between the wavelength of the light passing through the first reflection unit and the second reflection unit and the intensity of the light is calculated using one light.

  According to this application example, the calculation unit uses the second light to calculate the intensity of light having a wavelength of 400 nm or more and less than 480 nm. The calculation unit uses the first light to calculate the intensity of light with a wavelength of 480 nm or more and less than 700 nm. The calculation unit calculates the intensity of light having a wavelength of 400 nm or more and less than 700 nm. The relationship between the wavelength of light passing through the first reflecting portion and the second reflecting portion and the intensity of the light is taken as a spectrum. The computing unit can compute the spectrum of visible light. The calculation unit uses the second light to calculate the intensity of light having a wavelength of less than 480 nm. When the first light is used to calculate the intensity of light with a wavelength of less than 480 nm, the change speed of the distance between the reflecting portions is fast. Therefore, by using the second light instead of the first light, the calculation unit accurately measures the light intensity It can be calculated.

  The calculation unit uses the first light to calculate the intensity of light having a wavelength of 480 nm or more. Since the intensity of light of the first light is larger than that of the second light, it can be measured accurately. And, in the light having a wavelength of 480 nm or more, since the change speed of the distance between the reflection portions is not fast, it is possible to calculate the intensity of the light with high accuracy by using the first light. As a result, the computing unit can compute the intensity of light having a wavelength of 400 nm or more and less than 700 nm with high accuracy.

Application Example 3
The optical module according to the application example is characterized by including a band pass filter for suppressing the light receiving element to be irradiated with light having a wavelength of less than 400 nm and light having a wavelength of 700 nm or more.

  According to this application example, the optical module includes the band pass filter. The band pass filter suppresses that the light receiving element is irradiated with light having a wavelength of less than 400 nm and light having a wavelength of 700 nm or more. Therefore, it is possible to suppress that the light of the wavelength other than the first light and the second light used by the calculation unit affects the calculation of the spectrum.

Application Example 4
In the optical module according to the application example, the interval changing unit includes two electrodes that are interlocked and opposed to the first reflection unit and the second reflection unit, and a rectangular wave voltage is repeatedly applied between the electrodes. It is characterized by

  According to this application example, the space changer includes two opposing electrodes. Then, the interval changing unit repeatedly applies a rectangular wave voltage between the electrodes. By applying a voltage between the electrodes, an electrostatic force is generated between the electrodes, so the distance between the reflecting portions can be changed. And two opposing electrodes interlock | cooperate with a 1st reflection part and a 2nd reflection part. The interval changing unit can cause the first reflecting unit and the second reflecting unit to inherently vibrate by repeatedly applying a voltage. The voltage applied repeatedly between the electrodes is a rectangular wave. Since the rectangular wave is a waveform that can be formed with a simple circuit configuration of a single power supply and a switch circuit, the optical module can be easily manufactured.

Application Example 5
In the optical module according to the application example, the arithmetic unit inputs the intensity of light passing through the first reflecting portion and the second reflecting portion at a predetermined distance between the reflecting portions from the light receiving element multiple times, and the average value is obtained. To calculate.

  According to this application example, the light receiving element receives the light passing through the first reflecting portion and the second reflecting portion at a predetermined distance between the reflecting portions a plurality of times. Since the interval changing unit causes the first reflecting unit and the second reflecting unit to vibrate uniquely, the light receiving element can easily receive light passing through the first reflecting unit and the second reflecting unit at a predetermined distance between reflecting units multiple times Can. Then, the light receiving element outputs the intensity of the received light to the calculation unit. The arithmetic unit inputs the light intensity a plurality of times to calculate an average value. Therefore, even when the light intensity of the light received by the light receiving element varies, the optical module can output the average value. As a result, the optical module can output a value that is less susceptible to variations in light intensity.

Application Example 6
It is a spectrometry apparatus concerning this application example, Comprising: The variable-wavelength interference filter which has an electrostatic actuator which changes the gap amount which is a distance between a pair of reflecting films, and a pair of said reflecting films, The electrostatic actuator A filter drive unit that applies a periodic drive voltage, a gap detection unit that detects the gap amount, and outputs a gap detection signal corresponding to the detected gap amount, and receives light output from the variable wavelength interference filter A light receiving unit for outputting a light intensity detection signal corresponding to the light intensity of the received light; and an operation unit for calculating the relationship between the wavelength of light passing through the variable wavelength interference filter and the light intensity; When it is assumed that 2 integers are integers larger than the first integer, the calculation unit may calculate the intensity of the first light whose gap amount is the first integer multiple of the half wavelength of light, and The amount is characterized the intensity of the second light is the second integer multiple of the half wavelength of the light, the use of.

  According to this application example, the spectrometry apparatus includes the variable wavelength interference filter, the filter driver, the light receiver, and the calculator. The variable wavelength interference filter includes a pair of reflective films and an electrostatic actuator. Each reflective film is disposed at an interval of the gap amount. And each reflective film passes a part of light which injected, respectively, and reflects a part. The electrostatic actuator changes the gap amount. The gap detection unit detects a gap amount, and outputs a gap detection signal corresponding to the detected gap amount.

  Light having a gap amount equal to an integral multiple of half wavelengths passes through the pair of reflective films. Let the second integer be an integer greater than the first integer. Then, light whose gap amount is a first integer multiple of a half wavelength of light is taken as a first light, and light whose gap amount is a second integer multiple of a half wavelength of light is taken as a second light. The light passing through the pair of reflection films includes the first light and the second light.

  The light receiving unit receives the light output from the variable wavelength interference filter, and outputs a light intensity detection signal corresponding to the intensity of the received light. Then, the computing unit computes the relationship between the wavelength of light passing through the variable wavelength interference filter and the intensity of the light. The computing unit uses the intensity of the first light and the intensity of the second light. The intensity of light passing through the pair of reflective films is stronger in the first light than in the second light. The light with high intensity can measure the intensity more accurately than the light with low intensity. Therefore, the first light can measure the light intensity more accurately than the second light.

  The electrostatic actuator inherently vibrates the pair of reflective films to change the gap amount. At the timing when the amount of gap changes, there are a portion where the speed of the amount of gap change is fast and a portion where the speed is slow. And, in the portion where the change speed of the gap amount is fast, since the change of the wavelength of the passing light is fast, the variation of the measured value becomes large. Since the change of the wavelength of the passing light is slow where the change rate of the gap amount is slow, the variation of the measured value becomes small.

  The amount of gap differs between the first light and the second light in the light having the same wavelength. For this reason, the timing at which the change speed of the gap amount is fast differs from the timing at which the change speed of the gap amount is fast in the first light and the second light in the light having the same wavelength. Therefore, in the first light, when the change speed of the gap amount is fast, the calculation unit can calculate the light intensity with high accuracy by calculating the light intensity using the second light. As a result, the spectrometer can accurately output the light intensity with respect to the light wavelength.

Application Example 7
An electronic apparatus according to this application example is characterized by including the optical module described above.

  According to this application example, the electronic device includes the optical module described above. Each of the optical modules described above can output the intensity of the light with respect to the wavelength of the passing light with high accuracy. Therefore, the electronic device can be an electronic device provided with an optical module capable of accurately outputting the light intensity with respect to the wavelength of light.

Application Example 8
In the spectrometry method according to this application example, a first reflection unit that transmits a part of incident light and reflects a part of the incident light, and the first reflection unit are disposed to face each other, and a part of incident light is transmitted. A second reflecting portion that reflects a portion, and the first reflecting portion and the second reflecting portion are naturally vibrated to provide a distance between the reflecting portions that is a distance between the first reflecting portion and the second reflecting portion. An interval changing unit to be changed, an interval detecting unit for detecting the distance between the reflecting units, a light receiving element for receiving light passing through the first reflecting unit and the second reflecting unit to detect an intensity of the light; A spectroscopic measurement method using an optical module, comprising: an operation unit that calculates a relationship between the wavelength of light passing through a first reflection unit and the second reflection unit and the intensity of the light, the first reflection unit And a vibration step of causing the second reflection portion to vibrate inherently, a distance between the reflection portions, and light received by the light receiving element. A sampling step of sampling the intensity at a plurality of timings within a vibration period in which the first reflection unit and the second reflection unit are eigen-oscillated, and when the second integer is an integer greater than the first integer, the arithmetic unit An intensity of the first light whose distance between the reflecting portions is the first integer multiple of a half wavelength of light, and an intensity of a second light whose distance between the reflecting portions is the second integer multiple of a half wavelength of light And D. a spectrum calculation step of calculating a relation between the wavelength of light passing through the first reflection part and the second reflection part and the intensity of the light by using.

  According to this application example, the optical module includes the first reflecting unit, the second reflecting unit, the interval changing unit, the interval detecting unit, the light receiving element, and the computing unit. The first reflecting portion and the second reflecting portion are disposed to face each other. The first reflecting portion and the second reflecting portion respectively transmit a part of incident light and reflect a part. The first reflecting portion and the second reflecting portion are disposed at a predetermined interval, and the interval changing portion changes the distance between the first reflecting portion and the second reflecting portion. The distance between the first reflecting portion and the second reflecting portion is taken as the distance between the reflecting portions. The interval detection unit detects the distance between the reflection units. The light receiving element receives the light passing through the first reflecting portion and the second reflecting portion to detect the intensity of the light. Then, the computing unit computes the relationship between the wavelength of light passing through the first reflecting unit and the second reflecting unit and the intensity of the light.

  In the vibration process, the interval changing unit inherently vibrates the first reflecting unit and the second reflecting unit to change the distance between the reflecting units. Then, in the sampling step, the distance between the reflection portions detected by the interval detection portion is sampled, and the intensity of the light received by the light receiving element is sampled. This sampling is performed at a plurality of timings within a vibration period in which the first reflection portion and the second reflection portion naturally vibrate.

  Light in which the distance between the reflecting portions is equal to an integral multiple of a half wavelength passes through the first reflecting portion and the second reflecting portion. Let the second integer be an integer greater than the first integer. Then, light in which the distance between the reflecting portions is a first integer multiple of a half wavelength of light is taken as a first light, and light in which the distance between the reflecting portions is a second integer multiple of a half wavelength of light is taken as second light. The light passing through the first reflecting portion and the second reflecting portion includes the first light and the second light.

  In the spectrum calculation step, the calculation unit calculates the relationship between the wavelength of light passing through the first reflection unit and the second reflection unit and the light intensity. The computing unit uses the intensity of the first light and the intensity of the second light. The intensity of light passing through the first reflecting portion and the second reflecting portion is stronger in the first light than in the second light. The light with high intensity can measure the intensity more accurately than the light with low intensity. Therefore, the first light can measure the light intensity more accurately than the second light.

  At the timing when the distance between the reflective portions changes, there are a portion where the speed between the reflective portions changes is fast and a portion where the speed is slow. And, since the change of the wavelength of the passing light is fast in the part where the change speed of the distance between the reflection parts is fast, the variation of the measured value becomes large. Since the change of the wavelength of the passing light is slow at a place where the change speed of the distance between the reflection portions is slow, the variation of the measured value becomes small.

  The first light and the second light in the light having the same wavelength are different in the distance between the reflecting portions. For this reason, the timing at which the change speed of the distance between the reflection portions is fast differs from the timing at which the change speed between the reflection portions is fast for the first light and the second light in light having the same wavelength. Therefore, in the first light, when the change speed of the distance between the reflection parts is fast, the calculation part can calculate the light intensity with high accuracy by calculating the light intensity using the second light. As a result, the optical module can accurately output the light intensity with respect to the light wavelength.

FIG. 1 is a block diagram showing the configuration of a spectrometry apparatus according to a first embodiment. The figure for demonstrating the structure of a light receiver, a space | interval detection part, and a data conversion part. The electric block diagram which shows the structure of a control part. Flow chart of the measurement method. The figure for demonstrating the spectroscopy measurement method. The figure for demonstrating the spectroscopy measurement method. The figure for demonstrating the spectroscopy measurement method. The figure for demonstrating the spectroscopy measurement method. The figure for demonstrating the spectroscopy measurement method. The figure for demonstrating the spectroscopy measurement method. The figure for demonstrating the spectroscopy measurement method. The figure for demonstrating the spectroscopy measurement method. The figure for demonstrating the spectroscopy measurement method. FIG. 7 is a schematic front view showing the configuration of a gas detection device according to a second embodiment. The block diagram which shows the structure of the control system of a gas detection apparatus. The block diagram which shows the structure of the food-analysis apparatus in connection with 3rd Embodiment.

Hereinafter, embodiments will be described according to the drawings.
In addition, in order to make each member in each drawing into a size that can be recognized in each drawing, each member is illustrated with different scales.

First Embodiment
In the present embodiment, characteristic examples of a spectrometry device and a spectrometry method of performing spectrometry using this spectrometry device will be described with reference to the drawings. The spectrometer according to the first embodiment will be described according to FIGS. 1 to 3. FIG. 1 is a block diagram showing the configuration of a spectrometry apparatus. As shown in FIG. 1, the spectrometer 1 includes a light source 4 for irradiating the object 2 with light 3. In the spectrometry device 1, a portion not including the light source 4 is an optical module 1a. Therefore, the spectrometer 1 is composed of the light module 1a and the light source 4 and the like.

  The light source 4 is composed of a halogen lamp, an LED (Light Emitting Diode), or the like, and emits light 3 of a wavelength in a range to be measured. Although the range of the wavelength to measure is not specifically limited, For example, in this embodiment, it sets to 400 nm-700 nm. The emission spectrum of the light source 4 is preferably flat. The object to be measured 2 is an object to be subjected to the spectroscopic measurement, and the type of the object to be measured 2 is not particularly limited.

  The spectrometer 1 further includes a band pass filter 5, a variable wavelength interference filter 6, and a light receiver 7 as a light receiving unit. Part of the light 3 reflected by the device under test 2 passes through the band pass filter 5 and the variable wavelength interference filter 6 in this order to illuminate the light receiver 7.

  The band pass filter 5 is an optical component that suppresses the light 3 having a wavelength of less than 400 nm and the light 3 having a wavelength of 700 nm or more on the light receiver 7. The wavelength of the light 3 which the spectrometer 1 disperses is 400 nm or more and less than 700 nm. The band pass filter 5 suppresses the influence of the light 3 of the unnecessary wavelength by suppressing the passage of the light 3 of the wavelength outside the spectral range. In the band pass filter 5, a film formed by vapor deposition or the like is formed on a light transmitting substrate. The wavelength of the passing light 3 is limited by the material and thickness of the film.

  The variable wavelength interference filter 6 is an optical component that limits the wavelength of the passing light 3. The variable wavelength interference filter 6 includes a fixed substrate 8 and a movable substrate 9. The material of the fixed substrate 8 and the movable substrate 9 may be a light transmissive material, and for example, silica glass, quartz crystal, or the like can be used. The fixed substrate 8 and the movable substrate 9 are bonded by a bonding film 10. The bonding film 10 is a film used when bonding the fixed substrate 8 and the movable substrate 9. For the bonding film 10, for example, a film composed of a plasma-polymerized film containing siloxane as a main component can be used.

  The fixed substrate 8 is provided with a fixed reflection film 11 as a first reflection part and a reflection film, and a fixed electrode 12 as an electrode. The fixed reflection film 11 passes a part of the incident light 3 and reflects a part. The movable substrate 9 is provided with a movable reflection film 13 as a second reflection portion and a reflection film, and a movable electrode 14 as an electrode. The movable reflective film 13 passes a part of the incident light 3 and reflects a part. The fixed reflection film 11 and the movable reflection film 13 are disposed to face each other, and form a pair of reflection films. The distance between the fixed reflection film 11 and the movable reflection film 13 which are a pair of reflection films is taken as a distance 15 between reflection parts as a gap amount. The distance between the fixed reflection film 11 which is a pair of reflection films and the movable reflection film 13 is also referred to as a distance between the fixed reflection film 11 which is a pair of reflection films and the movable reflection film 13.

  The fixed substrate 8 has a rectangular plate shape. At the center of the fixed substrate 8, a reflective film setting portion 16 projecting in a cylindrical shape is installed. An electrode installation groove 17 recessed in an annular shape surrounding the reflection film installation portion 16 is installed. A first bonding portion 18 protruding in the upper direction in the figure is installed around the electrode installation groove 17. The first bonding portion 18 is a portion to be bonded to the movable substrate 9. The fixed substrate 8 is formed by processing a glass substrate having a thickness of, for example, 500 μm to 1000 μm.

  The fixed reflection film 11 is provided on the surface on the upper side in the drawing of the reflection film setting unit 16. As a material of the fixed reflective film 11, for example, a conductive reflective film such as a metal film of Ag or the like, an Ag alloy or the like, or a conductive alloy film is used. The fixed reflection film 11 also functions as a capacitance detection electrode for detecting the capacitance according to the distance 15 between the reflection portions. As the fixed reflection film 11, a dielectric multilayer film in which a high refractive layer and a low refractive layer are laminated may be used. In this case, for example, by forming a conductive metal alloy film on the lowermost layer or surface layer of the dielectric multilayer film, the fixed reflection film 11 can function as a capacitance detection electrode.

  In addition, the fixed reflection film 11 may be overlaid on a metal film to set a transparent conductive material. As a transparent conductive material, materials such as ITO (Indium Tin Oxide), IGO (Indium-gallium oxide), ICO (indium-doped cadmium oxide), etc. can be used. In the present embodiment, ITO is used as the material of the fixed reflection film 11, for example.

  The fixed electrode 12 is installed in the electrode installation groove 17. The shape of the fixed electrode 12 is annular. The material of the fixed electrode 12 is not particularly limited as long as it is conductive and easy to form a film. In the present embodiment, for example, ITO is used as the material of the fixed electrode 12. A metal film such as a TiW film can also be used as the material of the fixed electrode 12.

  An annular groove 21 surrounding the center is provided on the upper surface of the movable substrate 9 in the drawing. A cylindrical portion surrounded by the groove 21 is referred to as a movable portion 22. The movable portion 22 is disposed to face the reflective film installation portion 16 of the fixed substrate 8. Since the thickness of the movable substrate 9 is thin at the portion of the groove 21, it is easily deformed. Therefore, the movable portion 22 can be easily moved in the vertical direction in the drawing. The movable substrate 9 is formed by subjecting a glass substrate having a thickness of, for example, 300 μm to 1000 μm to a process such as planar polishing.

  A movable reflection film 13 is provided on the lower surface of the movable portion 22 in the drawing. The material of the movable reflective film 13 is the same as that of the fixed reflective film 11. The movable reflective film 13 also functions as a capacitance detection electrode for detecting the capacitance according to the distance 15 between the reflection portions.

  The movable electrode 14 is disposed around the movable reflective film 13 and has an annular planar shape like the fixed electrode 12. The movable electrode 14 is disposed at a position facing the fixed electrode 12. When a voltage is applied between the fixed electrode 12 and the movable electrode 14, an electrostatic force is generated between the fixed electrode 12 and the movable electrode 14 due to static electricity. The fixed substrate 8 and the movable substrate 9 are actuators in which the portion of the groove 21 of the movable substrate 9 is deformed by electrostatic force and the distance between the fixed electrode 12 and the movable electrode 14 is changed. When the distance between the fixed electrode 12 and the movable electrode 14 changes, the inter-reflection portion distance 15 changes. The material of the fixed electrode 12 is the same as the material of the movable electrode 14.

  Thus, the electrostatic actuator 23 is configured by the fixed substrate 8, the movable substrate 9, the fixed electrode 12, the movable electrode 14 and the like. The electrostatic actuator 23 of the variable wavelength interference filter 6 changes the distance 15 between the reflecting portions. By changing the inter-reflecting portion distance 15, the variable wavelength interference filter 6 can pass the light 3 of the wavelength according to the inter-reflecting portion distance 15.

  A light receiver 7 is disposed on the upper side of the variable wavelength interference filter 6 in the drawing. The light receiver 7 is provided with a light receiving element 24. The light receiving element 24 receives the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 and detects the intensity of the light 3. The light receiver 7 receives the light 3 output from the variable wavelength interference filter 6 and outputs a light intensity detection signal corresponding to the intensity of the received light.

  The spectrometer 1 includes a controller 25 that controls the spectrometer 1. The control device 25 includes a control unit 26, a light source drive unit 27, a data conversion unit 28, an interval detection unit 29 as a gap detection unit, and an actuator drive unit 30 as a filter drive unit. The control unit 26 controls the light source drive unit 27, the interval detection unit 29, the actuator drive unit 30, and the like, and calculates the spectrum of the light 3 using the input data.

  The light source drive unit 27 is electrically connected to the control unit 26 and the light source 4. The light source drive unit 27 turns on and off the light source 4 in accordance with an instruction signal from the control unit 26. In addition, the intensity of the light 3 emitted by the light source 4 is controlled so that the intensity of the light 3 reflected by the object to be measured 2 becomes appropriate.

  The data conversion unit 28 is electrically connected to the control unit 26, the interval detection unit 29, and the light receiver 7. The data converter 28 receives the voltage signal output from the light receiver 7. Then, the data conversion unit 28 reduces the noise of the input voltage signal. Further, the data conversion unit 28 converts the voltage signal into digital data and outputs the digital data to the control unit 26.

  The interval detection unit 29 is electrically connected to the data conversion unit 28, the fixed reflection film 11, and the movable reflection film 13. The interval detection unit 29 samples the voltage between the fixed reflection film 11 and the movable reflection film 13 and outputs the sampled voltage to the data conversion unit 28. A voltage between the fixed reflection film 11 and the movable reflection film 13 is used as a gap detection unit output voltage as a gap detection signal. The data conversion unit 28 receives the voltage signal output from the interval detection unit 29. Then, the data conversion unit 28 reduces the noise of the input voltage signal. Further, the data conversion unit 28 converts the voltage signal into digital data and outputs the digital data to the control unit 26. Data indicating the interval detection unit output voltage is input to the control unit 26. Thus, the interval detection unit 29 detects the inter-reflection unit distance 15 and outputs an interval detection unit output voltage corresponding to the detected inter-reflection unit distance 15.

  The actuator drive unit 30 is electrically connected to the control unit 26, the fixed electrode 12 and the movable electrode 14. The actuator drive unit 30 outputs a drive signal to the fixed electrode 12 and the movable electrode 14 based on the control signal from the control unit 26. Although the waveform of the drive signal is not particularly limited, in the present embodiment, for example, it is a pulse voltage of a rectangular wave, and its peak voltage is 5 V or less. The drive signal is a voltage signal that is periodically driven. Thus, the actuator drive unit 30 applies a periodic drive voltage to the electrostatic actuator 23. The fixed reflection film 11 and the movable reflection film 13 inherently vibrate due to the applied periodic drive voltage. As described above, the electrostatic actuator 23 causes the fixed reflection film 11 and the movable reflection film 13 to vibrate uniquely to change the distance 15 between the reflection portions.

  A gap changing unit 39 is configured by the electrostatic actuator 23 and the actuator driving unit 30 and the like. The interval changing unit 39 includes a fixed electrode 12 and a movable electrode 14 which are interlocked and opposed to the fixed reflection film 11 and the movable reflection film 13. Then, the actuator drive unit 30 repeatedly applies a rectangular wave voltage between the fixed electrode 12 and the movable electrode 14. The actuator driver 30 causes the fixed reflection film 11 and the movable reflection film 13 to vibrate uniquely by repeatedly applying a voltage. The voltage repeatedly applied between the fixed electrode 12 and the movable electrode 14 is a rectangular wave. The rectangular wave is a waveform that can be formed with an easy circuit configuration of a single power supply and a switch circuit, so the spectrometer 1 can be easily manufactured. The actuator drive unit 30 includes an inverter circuit and the like, and can change the frequency of the drive signal.

  The control unit 26 inputs data corresponding to the inter-reflection unit distance 15 from the interval detection unit 29 and the data conversion unit 28. Then, the control unit 26 inputs data corresponding to the intensity of the light 3 that has passed through the variable wavelength interference filter 6 from the light receiver 7 and the data conversion unit 28. The control unit 26 controls the inter-reflector distance 15 to collect data of the wavelength and light intensity of the light 3 passing through the variable wavelength interference filter 6. The spectrometer 1 then calculates the spectrum of the light 3 reflected by the object 2 to be measured.

  FIG. 2 is a diagram for explaining the configuration of the light receiver, the interval detection unit, and the data conversion unit. As shown in FIG. 2, the light receiver 7 is composed of a light receiving element 24, a current / voltage conversion circuit 31, an amplification circuit 32, and the like. The light receiving element 24 is a photoelectric conversion element such as a photodiode. The light receiving element 24 receives the light that has passed through the variable wavelength interference filter 6, and outputs a current signal corresponding to the intensity of the received light to the current voltage conversion circuit 31.

  The current-voltage conversion circuit 31 is configured by an operational amplifier, a resistor, a capacitor, and the like. The current voltage conversion circuit 31 receives a current signal from the light receiving element 24 and converts the current signal into a voltage signal. Then, the converted voltage signal is output to the amplifier circuit 32. The amplifier circuit 32 is a programmable gain amplifier. The amplification circuit 32 amplifies the gain by varying the gain so that the output of the current-voltage conversion circuit 31 is in a desired dynamic range. The amplification circuit 32 receives and amplifies the voltage signal output from the current-voltage conversion circuit 31, and outputs the amplified signal as a light intensity detection signal to the data conversion unit.

  The data conversion unit 28 is provided with a first low pass filter 33, a second low pass filter 34, an AD converter 35 (analog digital), and the like. The first low pass filter 33 and the second low pass filter 34 are configured by an operational amplifier, a resistor, a capacitor, and the like. The first low pass filter 33 and the second low pass filter 34 attenuate high frequency components contained in the signal.

  The AD converter 35 has two input ports. The AD converter 35 can sample data input from two input ports simultaneously. One of the input ports of the AD converter 35 receives the light intensity detection signal from the light receiver 7. One of the input ports of the AD converter 35 receives a signal indicating the interval detection unit output voltage from the interval detection unit 29. The AD converter 35 receives the sampling signal from the control unit 26. When performing AD conversion processing, a sampling signal is used. Then, the AD converter 35 simultaneously performs AD conversion processing on the interval detection unit output voltage and the light intensity detection signal which are analog signals.

  The first low pass filter 33 is electrically connected to the amplifier circuit 32 and the AD converter 35. The first low pass filter 33 receives the light intensity detection signal from the amplification circuit 32. Then, noise included in the light intensity detection signal is reduced. This noise includes the noise added by the light receiver 7. The first low pass filter 33 outputs the light intensity detection signal with reduced noise to the AD converter 35. The AD converter 35 converts the light intensity detection signal into digital data and outputs the digital data to the control unit 26.

  The second low pass filter 34 is electrically connected to the interval detection unit 29 and the AD converter 35. The second low pass filter 34 receives a signal indicating the interval detection unit output voltage from the interval detection unit 29. Then, the second low pass filter 34 reduces noise included in the signal indicating the interval detection unit output voltage. This noise includes the noise added by the interval detection unit 29. The second low pass filter 34 outputs, to the AD converter 35, a signal indicating the interval detection unit output voltage with reduced noise. The AD converter 35 converts a signal indicating the interval detection unit output voltage into digital data and outputs the digital data to the control unit 26.

  FIG. 3 is an electrical block diagram showing the configuration of the control unit. In FIG. 3, the control unit 26 includes a CPU 36 (central processing unit) that performs various types of arithmetic processing as a processor, and a memory 37 as a storage unit that stores various types of information. The light source drive unit 27, the actuator drive unit 30, the data conversion unit 28, the interval detection unit 29, the input device 38 and the display device 41 are connected to the CPU 36 via the input / output interface 42 and the data bus 43.

  The input device 38 is a device for the operator to input an instruction command and measurement conditions to the CPU 36. The input device 38 is a device such as a keyboard and a touch panel. The touch panel is a transparent sheet-like switch disposed on the surface of the display device 41. As the display device 41, a liquid crystal display device, an organic electroluminescence display, a plasma display, or a surface electric field display can be used. The display device 41 displays the status of measurement, measurement results, and the like.

  The memory 37 is a concept including a semiconductor memory such as a RAM and a ROM, and an external storage device such as a hard disk. The memory 37 stores a program 44 in which the control procedure of the operation of the spectrometry device 1 and the calculation procedure of the distance measurement are described. In addition, the memory 37 stores interval data 45 which is data of the measured inter-reflector distance 15. In addition, the memory 37 stores wavelength conversion table data 46 which is data for converting data of the inter-reflecting portion distance 15 into wavelengths. The wavelength conversion table data 46 includes a table for converting the interval detection unit output voltage into the inter-reflection unit distance 15. Furthermore, the wavelength conversion table data 46 includes a table for converting the interval detection unit output voltage into a wavelength. In addition, the memory 37 stores light intensity data 47 which is data of the intensity of the light 3 detected by the light receiver 7. Besides, the memory 37 stores spectrum data 48 which is data of the spectrum of the light 3 calculated by the CPU 36. In addition, the memory 37 includes a work area for the CPU 36, a storage area functioning as a temporary file or the like, and various other storage areas.

  The CPU 36 controls the light source 4, the variable wavelength interference filter 6 and the light receiver 7 in accordance with the program 44 stored in the memory 37. The CPU 36 calculates the spectrum of the light 3 using the data of the intensity of the light 3 detected by the light receiver 7 after passing through the variable wavelength interference filter 6 and displays the result on the display device 41. The CPU 36 on which the program 44 operates has a light source control unit 49 as a specific function implementing unit. The light source control unit 49 outputs a control signal to the light source drive unit 27 and causes the light source drive unit 27 to drive the light source 4. Then, the light source control unit 49 controls the on / off of the light source 4 and the intensity of the light 3 emitted by the light source 4.

  In addition, the CPU 36 has an actuator control unit 50. The actuator control unit 50 outputs a control signal to the actuator drive unit 30 to cause the actuator drive unit 30 to drive the electrostatic actuator 23. Then, the actuator control unit 50 controls the operation start, the operation stop, the adjustment of the amplitude and the vibration cycle of the electrostatic actuator 23.

  In addition, the CPU 36 has an interval measurement control unit 51. The interval measurement control unit 51 outputs a control signal to the interval detection unit 29 to control the operation of the interval detection unit 29. The space | interval detection part 29 detects a space | interval detection part output voltage, and the data conversion part 28 converts into digital data. The data conversion unit 28 includes a timer. Then, the data conversion unit 28 outputs data indicating the voltage between the fixed reflection film 11 and the movable reflection film 13 and data of measurement time to the interval measurement control unit 51. The interval measurement control unit 51 inputs the converted data and measurement time data, and stores the data as interval data 45 in the memory 37.

  Besides, the CPU 36 has a light intensity measurement control unit 52. The data converter 28 detects the intensity of the light 3 received by the light receiver 7 and converts it into digital data. Then, the data conversion unit 28 outputs data indicating the intensity of the light 3 received by the light receiver 7 and data of the measurement time to the light intensity measurement control unit 52. The light intensity measurement control unit 52 inputs the converted data and the data of measurement time and stores the data as light intensity data 47 in the memory 37.

  In addition, the CPU 36 has an arithmetic unit 53. The computing unit 53 computes the relationship between the wavelength of the light 3 transmitted through the fixed reflection film 11 and the movable reflection film 13 of the variable wavelength interference filter 6 and the intensity of the light 3 using the input data. The relationship between the wavelength of the light 3 and the intensity of the light 3 corresponds to a spectrum. The calculation unit 53 includes a light intensity calculation unit 54. The light intensity calculation unit 54 combines the data indicating the interval detection unit output voltage measured at the same time with the data indicating the light intensity detected by the light receiver 7 into a data array. In this data arrangement, data indicating the output voltage of the interval detection unit and data indicating the light intensity detected by the light receiver 7 are arranged in time series.

  The interval detector output voltage is repeated at a predetermined cycle. When the inter-reflecting portion distance 15 is the smallest, the interval detecting portion output voltage becomes maximum. The light intensity calculator 54 forms a data array on the basis of the time when the interval detector output voltage becomes maximum. In the data arrangement, data indicating the output voltage of the interval detection unit decreases from the maximum value to become the minimum value, and data for one cycle while increasing from the minimum value to the maximum value is one data arrangement. Therefore, the number of data arrays is the number of times the variable wavelength interference filter 6 vibrates during the measurement period.

  Besides, the calculation unit 53 includes an average value calculation unit 55. The average value calculation unit 55 calculates an average of a plurality of data arrays. It is assumed that the data array includes data of n interval detection unit output voltages and data indicating n light intensities. The number of times the variable wavelength interference filter 6 vibrates during the measurement period is m times. At this time, the number of data arrays is m.

  Let i be an integer, and let the i-th value of the data of the interval detection unit output voltage in one data array be Xi. The i-th value of data indicating light intensity is taken as Yi. i is a number in the range of 1 to n. When j is an integer and m data arrays are arranged in the order of measurement, the order is indicated by j. j is a number in the range of 1 to m.

  Let Xi in the j-th data array be Xij. Let Yi in the j-th data array be Yij. Then, a value obtained by dividing the operation value of Xi1 + Xi2 +... + Xim by m is taken as an average Xi. When i is arranged in order from 1, the array of Xi is an array of time series. Similarly, a value obtained by dividing the operation value of Yi1 + Yi2 +... + Yim by m is taken as an average Yi. The array of Yi is an array of time series. An array combining the average Xi and the average Yi is taken as an average data array. The average value calculator 55 calculates an average data array.

  Xi is data corresponding to a predetermined inter-reflector distance 15. And, Yi is data corresponding to the intensity of light passing through the fixed reflection film 11 and the movable reflection film 13. The average value calculator 55 receives the intensity of light 3 passing through the fixed reflection film 11 and the movable reflection film 13 at a predetermined distance 15 between the reflection parts from the light receiving element 24 by the CPU 36 several times, and the average value calculator 55 Calculate the average value.

  Besides, the calculation unit 53 includes a spectrum calculation unit 56. The spectrum calculator 56 calculates a spectrum using the average data array. At this time, the spectrum calculation unit 56 converts the data of the interval detection unit output voltage into the wavelength of the light 3 using the wavelength conversion table data 46. Then, the wavelength of the light 3 is converted to a frequency. Next, a spectrum indicating the distribution of the intensity of the light 3 with respect to the frequency of the light 3 is calculated by calculating the relationship between the intensity of the light 3 with the frequency of the light 3.

  In addition, the CPU 36 has a functional unit (not shown), and performs control to display the spectrum of the calculation result on the display device 41, for example. Besides, the CPU 36 performs control to display information on display and measurement of the state of the apparatus on the display device 41.

  Next, the spectrometry method which the spectrometry apparatus 1 mentioned above performs is demonstrated with FIGS. 4-13. FIG. 4 is a flowchart of the measurement method. In the flowchart of FIG. 4, step S1, step S2 and step S3 are performed in parallel. Step S1 corresponds to a vibration process. This step is a step of causing the fixed reflection film 11 and the movable reflection film 13 to vibrate inherently. Next, the process proceeds to step S4. Step S2 is a light irradiation process. This step is a step in which the light source 4 irradiates the object 3 with the light 3. Next, the process proceeds to step S4. Step S3 is a sampling process. This step is a step of sampling the distance 15 between the reflection portions and the intensity of the light 3 received by the light receiving element 24 at a plurality of timings within a vibration cycle in which the fixed reflection film 11 and the movable reflection film 13 inherently vibrate. In this process, a predetermined number of vibrations are performed. And while step S3 continues, step S1 and step S2 are also performed. Next, the process proceeds to step S4.

  Step S4 is an averaging process. This process is a process in which the average value calculation unit 55 calculates an average data array. Next, the process proceeds to step S5. Step S5 is a spectrum calculation process. This process is a process in which the spectrum calculation unit 56 calculates the intensity distribution of the light 3 with respect to the frequency or wavelength of the light 3. The process of the spectroscopy measurement is complete | finished by the above process.

  5 to 13 are diagrams for explaining the spectrometry method. Next, the measurement method will be described in detail in correspondence with the steps shown in FIG. 4 using FIGS. 1 and 5 to 13. FIG. 5 is a diagram corresponding to the vibration process of step S1 and the sampling process of step S3. In FIG. 5, the horizontal axis indicates the passage of time, and the time shifts from left to right in the drawing. The vertical axis shows the voltage and the distance 15 between the reflecting portions. The voltage is higher in the upper side than in the lower side in the figure. The distance between the reflecting portions 15 is such that the upper side in the drawing is longer than the lower side.

  A drive voltage transition line 57 represents a voltage waveform of a drive signal applied by the actuator drive unit 30 between the fixed electrode 12 and the movable electrode 14. As shown in the drive voltage transition line 57, the voltage waveform of the drive signal is a rectangular pulse voltage, and the peak voltage of the drive signal is 5 V or less. The frequency of the drive signal is equal to the natural frequency of the electrostatic actuator 23. Thus, the variable wavelength interference filter 6 can vibrate at a voltage of 5 V or less.

  The inter-reflector distance transition line 58 indicates the transition of the inter-reflector distance 15. As the inter-reflecting portion distance transition line 58 shows, the period of the inter-reflecting portion distance 15 is the same as the period of the drive voltage transition line 57. The inter-reflector distance transition line 58 is a curve close to a sine wave. When a voltage is applied between the fixed electrode 12 and the movable electrode 14, the distance 15 between the reflecting portions is reduced. When a voltage is not applied between the fixed electrode 12 and the movable electrode 14, the distance 15 between the reflecting portions becomes large.

  When the application of the drive signal is started, the amplitude of the inter-reflector distance transition line 58 is small and gradually increases. Then, after passing a predetermined time, the amplitude of the inter-reflecting portion distance transition line 58 is stabilized. The sampling process of step S3 is performed after the amplitude of the inter-reflecting portion distance transition line 58 is stabilized. The vibration of the fixed reflection film 11 and the movable reflection film 13 is performed a plurality of times. The drive voltage transition line 57 and the inter-reflector distance transition line 58 indicate a part of the vibration.

  In the light irradiation process of step S2, as shown in FIG. 1, light 3 is irradiated from the light source 4 toward the object 2 to be measured. Part of the light 3 reflected by the DUT 2 passes through the band pass filter 5. The band pass filter 5 passes light 3 having a wavelength of 400 nm or more and less than 700 nm. The light 3 having passed through the band pass filter 5 travels toward the fixed reflection film 11 and the movable reflection film 13 of the variable wavelength interference filter 6. Then, light 3 of a specific wavelength passes through the variable wavelength interference filter 6 and illuminates the light receiving element 24 of the light receiver 7.

  5-8 is a figure corresponding to the sampling process of step S3. In step S3, the interval detection unit 29 outputs an interval detection unit output voltage. The interval detection unit output voltage is a voltage between the fixed reflection film 11 and the movable reflection film 13. Then, the interval detection unit 29 samples the inter-reflection unit distance 15 at a plurality of timings within a vibration period in which the fixed reflection film 11 and the movable reflection film 13 inherently vibrate. Since the interval detection unit 29 can not directly sample the inter-reflection unit distance 15, it samples an interval detection unit output voltage that is correlated with the inter-reflection unit distance 15. The vibration of the fixed reflection film 11 and the movable reflection film 13 is performed a plurality of times in step S1. Then, data corresponding to the predetermined number of vibrations is sampled also in step S3.

  In FIG. 5, the interval detection unit output voltage transition line 61 indicates the transition of the interval detection unit output voltage. When the value of the inter-reflecting portion distance 15 is small, the value of the interval detection portion output voltage transition line 61 is large, and the change is rapid. When the value of the inter-reflecting portion distance 15 is large, the value of the interval detection portion output voltage transition line 61 is small, and the change becomes gentle.

  FIG. 6 is a diagram showing the relationship between the interval detection unit output voltage and the distance between the reflection units. In FIG. 6, the horizontal axis indicates the interval detection unit output voltage, and the right side in the drawing is a voltage larger than the left side. The vertical axis indicates the distance between the reflecting portions 15, and in the figure, the upper side is a longer distance than the lower side. Then, as indicated by the correlation line 62, the interval detection unit output voltage and the distance between the reflection units 15 are in inverse proportion to each other. The fixed reflection film 11 and the movable reflection film 13 function as an electrostatic capacitance having a charge. At this time, it is known that the interval detection unit output voltage is in inverse proportion to the distance between the reflection units 15. As described above, the interval detection unit output voltage has a phase difference of 15 between the reflection units. Therefore, the interval detection unit output voltage is a signal used to detect the inter-reflection unit distance 15.

  FIG. 7 is a diagram showing transition of the interval detection unit output voltage, and is a diagram in which the interval detection unit output voltage transition line 61 of FIG. 5 is enlarged in the time axis direction. The vertical and horizontal axes in FIG. 7 are the same as in FIG. When the interval detection unit 29 and the data conversion unit 28 sample the interval detection unit output voltage, the time at which the peak 61 a of the interval detection unit output voltage transition line 61 is reached is used as a reference. Then, the interval detection unit 29 and the data conversion unit 28 sample the interval detection unit output voltage at a predetermined sampling interval. The sampled data is stored in the memory 37 as part of the interval data 45.

  Furthermore, in this step, the light receiving device 7 and the data conversion unit 28 sample the intensity of the light 3 received by the light receiving element 24 at a plurality of timings within the oscillation period in which the fixed reflection film 11 and the movable reflection film 13 are intrinsically vibrated. FIG. 8 shows the transition of the light intensity detection signal. The light intensity detection signal is a signal output from the light receiver 7 to the light intensity measurement control unit 52 via the data conversion unit 28. In FIG. 8, the horizontal axis indicates the passage of time, and the time shifts from left to right in the drawing. The vertical axis indicates the light intensity detection signal, and the upper side in the drawing is a voltage larger than the lower side. The larger the voltage is, the stronger the intensity of the light 3 received by the light receiving element 24 is. The light intensity detection signal transition line 63 shows an example of the transition of the light intensity detection signal.

  With the variable wavelength interference filter 6, the distance 15 between the reflecting portions changes with the passage of time. The light 3 having a distance between the reflection portions 15 equal to a half wavelength or one wavelength passes through the variable wavelength interference filter 6 and illuminates the light receiving element 24. As shown by the light intensity detection signal transition line 63, the light intensity detection signal becomes large when the half wavelength or one wavelength of the light 3 reflected by the object to be measured 2 becomes equal to the distance between the reflection portions 15.

  In the averaging step of step S4, the average value calculating unit 55 interpolates data between the sampled light intensity detection signal and the measurement time of the interval detection unit output voltage. A well-known method can be used for the interpolation method. For example, polynomial interpolation such as Newton interpolation or Lagrange interpolation, spline interpolation, linear interpolation, parabola interpolation, or the like can be used. The interpolation method is not particularly limited, but in the present embodiment, for example, spline interpolation is used.

  The average value calculation unit 55 calculates the average of the interpolated light intensity detection signal and the interval detection unit output voltage. The vibration of the fixed reflection film 11 and the movable reflection film 13 is performed a plurality of times in step S1. Then, data is sampled a plurality of times in step S3. In the light intensity detection signal and the data of the interval detection unit output voltage, the peak 61 a in the interval detection unit output voltage transition line 61 is the reference of the time axis. In step S4, the average value calculation unit 55 calculates an average value by combining the reference of the time axis, adding data plural times, and dividing by the number of additions. Therefore, even when the intensity of the light 3 received by the light receiving element 24 varies, the spectrometer 1 can output the average value.

  6 to 10 correspond to the spectrum calculation process of step S5. The inter-reflection unit distance 15 and the interval detection unit output voltage are divided into six areas and described with reference to FIGS. 6 and 9 to 11. FIG. 9 is a diagram showing the transition of the interval detection unit output voltage. 10 and 11 are diagrams showing the transition of the distance between the reflective portions, and FIG. 11 is a diagram in which a part of FIG. 10 is enlarged. The horizontal and vertical axes in FIGS. 9 to 11 are the same as those in FIG. 9 and 10, the vertical axis of the interval detection unit output voltage transition line 61 is the interval detection unit output voltage, and the vertical axis of the inter-reflection unit distance transition line 58 is the distance between reflection units.

  In FIG. 6, FIG. 9 and FIG. 10, a region where the distance between the reflection portions 15 is short and the distance detection portion output voltage is high is taken as a first region 64. As shown in FIG. 9, the first region 64 is a region not suitable for detecting the distance between the reflection portions 15 because the rate of change of the output voltage of the distance detection portion is large. The region where the inclination of the interval detection unit output voltage transition line 61 is large is the region where the change rate is large, and the region where the inclination of the interval detection unit output voltage transition line 61 is small is the region where the change rate is small. Therefore, the first area 64 is an unused area. In the first region 64, the light 3 passing through the variable wavelength interference filter 6 has a wavelength of less than 400 nm. The light 3 having a wavelength of less than 400 nm is suppressed by the band pass filter 5 from traveling to the variable wavelength interference filter 6. Therefore, the first area 64 is an area where the variable wavelength interference filter 6 is not used.

  In FIG. 6, FIG. 9 and FIG. 10, a region where the inter-reflecting portion distance 15 is longer than the first region 64 is referred to as a second region 65. In the second region 65, the light 3 passing through the variable wavelength interference filter 6 has a wavelength of 400 nm or more and less than 480 nm. As shown in FIG. 11, in the second region 65, the light 3 having the distance 15 between the reflection parts equal to the half wavelength of the light 3 passes through the variable wavelength interference filter 6. The light 3 in which the inter-reflecting portion distance 15 is equal to the half wavelength of the light 3 is also referred to as the light of the primary peak. Accordingly, in the second region 65, the light 3 of the primary peak passes through the variable wavelength interference filter 6. As shown in FIG. 9, in the second area 65, the rate of change of the output voltage of the interval detection section is large, so this area is not suitable for detecting the distance 15 between the reflection sections.

  In FIG. 6, FIG. 9 and FIG. 10, a region where the distance between the reflecting portions 15 is longer than the second region 65 is taken as a third region 66. In the third region 66, the light 3 passing through the variable wavelength interference filter 6 has a wavelength of 480 nm or more and less than 700 nm. As shown in FIG. 11, in the third region 66, the light 3 having the distance 15 between the reflection parts equal to the half wavelength of the light 3 passes through the variable wavelength interference filter 6. Accordingly, in the third region 66, the light 3 of the primary peak passes through the variable wavelength interference filter 6. As shown in FIG. 9, in the third region 66, the rate of change of the output voltage of the interval detection unit is not large, so it is a region suitable for detecting the distance 15 between the reflective portions.

  In FIGS. 6, 9 and 10, a region where the distance 15 between the reflecting portions is longer than the third region 66 is referred to as a fourth region 67. In the fourth region 67, the light 3 passing through the variable wavelength interference filter 6 has a wavelength of less than 400 nm and 700 nm or more. The light 3 having a wavelength of less than 400 nm is suppressed by the band pass filter 5 from traveling to the variable wavelength interference filter 6. The travel of the light 3 having a wavelength of 700 nm or more to the variable wavelength interference filter 6 is suppressed by the band pass filter 5. Therefore, the fourth area 67 is an area where the variable wavelength interference filter 6 is not used.

  In FIG. 6, FIG. 9 and FIG. 10, a region where the inter-reflection portion distance 15 is longer than the fourth region 67 is referred to as a fifth region 68. In the fifth region 68, the light 3 passing through the variable wavelength interference filter 6 has a wavelength of 400 nm or more and less than 480 nm. As shown in FIG. 11, in the fifth region 68, the light 3 having the distance 15 between the reflection parts equal to one wavelength of the light 3 passes through the variable wavelength interference filter 6. The light 3 in which the inter-reflecting portion distance 15 is equal to one wavelength of the light 3 is also referred to as light of secondary peak. Accordingly, in the fifth region 68, the light 3 of the secondary peak passes through the variable wavelength interference filter 6. As shown in FIG. 9, in the fifth area 68, the rate of change of the output voltage of the interval detection section is not large, so it is an area suitable for detecting the distance 15 between the reflection sections.

  In FIG. 6, FIG. 9 and FIG. 10, a region where the distance between the reflecting portions 15 is longer than the fifth region 68 is taken as a sixth region 69. In the sixth region 69, the light 3 passing through the variable wavelength interference filter 6 has a wide wavelength range. As shown in FIG. 9, in the sixth region 69, the change in the output voltage of the interval detection unit is small. However, since the change of the output voltage of the interval detection unit is too small to detect the inter-reflector distance 15, the region is not suitable.

  As described above, the fifth region 68 is suitable for the light 3 having a wavelength of 400 nm or more and less than 480 nm. The third region 66 is suitable for light 3 having a wavelength of 480 nm or more and less than 700 nm. In FIG. 11, the light 3 in which the inter-reflecting portion distance 15 is equal to a half wavelength is taken as the first light 70, and the light 3 in which the inter-reflecting portion distance 15 is equal to one wavelength is taken as the second light 71. The first light 70 corresponds to the light 3 of the primary peak, and the second light 71 corresponds to the light 3 of the secondary peak.

  In FIG. 7, the third region 66 and the fifth region 68 are used to detect the interval detection unit output voltage. The third region 66 and the fifth region 68 are suitable for detecting the inter-reflecting portion distance 15 because the rate of change of the output voltage of the interval detection portion is smaller than that of the second region 65.

  In FIG. 8, the peak generated in the second region 65 is referred to as a first peak 63a. The peak generated in the fifth region 68 is taken as a second peak 63 b. The first peak 63a and the second peak 63b are peaks at which the light 3 of the same wavelength is detected. Although both the first peak 63a and the second peak 63b can be detected, the light intensity detection is performed using the second peak 63b because the fifth region 68 can detect the output voltage of the interval detection unit with high accuracy.

  The peak generated in the third region 66 is referred to as a third peak 63c. The third area 66 is an area where it is easy to detect both the light intensity detected by the light receiving element 24 and the output voltage of the interval detection unit. Therefore, light intensity detection is performed using the third peak 63c.

  FIG. 12 is a diagram showing the correlation between the wavelength of light and the output voltage of the interval detection unit. The horizontal axis of FIG. 12 indicates the wavelength of the light 3 passing through the variable wavelength interference filter 6, and the wavelength on the right side of the figure is longer than that on the left side. The vertical axis indicates the interval detection unit output voltage, and the upper side in the drawing is a voltage higher than the lower side. The first-order correlation line 72 indicates an interphase of the first light 70. The second-order correlation line 73 indicates an interphase of the second light 71.

  The portion of the fifth region 68 of the second-order correlation line 73 is used for light 3 having a wavelength of 400 nm or more and less than 480 nm. Then, the wavelength is calculated from the interval detection unit output voltage. At this time, the light intensity of the second light 71 is used. The portion of the third region 66 of the first-order correlation line 72 is used for light 3 having a wavelength of 480 nm or more and less than 700 nm. Then, the wavelength is calculated from the interval detection unit output voltage. At this time, the light intensity of the first light 70 is used.

  The spectrum calculation unit 56 calculates a spectrum using the intensity of the first light 70 and the intensity of the second light 71. The first integer is 1 and the second integer is 2. At this time, the second integer is an integer larger than the first integer. Then, the spectrum calculation unit 56 calculates the intensity of the first light 70 whose inter-reflection part distance 15 is the first integer multiple of the half wavelength of the light 3 and the second integer multiple of the half inter-reflection part distance 15 of the light 3 And the intensity of the second light 71.

  The spectrum calculation unit 56 calculates the relationship between the wavelength of the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 and the intensity of the light 3, that is, the spectrum. At this time, the spectrum calculation unit 56 uses the second light 71 to calculate the intensity of the light 3 having a wavelength of 400 nm or more and less than 480 nm, and uses the first light 70 to calculate the light intensity of a wavelength of 480 nm or more and less than 700 nm. ing.

  The wavelength conversion table data 46 of the memory 37 includes data of a table for converting the interval detection unit output voltage into a wavelength. The spectrum calculation unit 56 performs calculation to convert data of the interval detection unit output voltage into the wavelength of the light 3. Then, an arrangement in which the wavelength of the light 3 and the light intensity are combined is calculated.

  FIG. 13 is a diagram for explaining the calculation result of the light intensity with respect to the wavelength. In FIG. 13, the horizontal axis indicates the wavelength of light, and the right side in the drawing is a longer wavelength than the left side. The vertical axis indicates the light intensity, and indicates the intensity of the light 3 received by the light receiving element 24. In the figure, the light intensity is higher at the upper side than at the lower side.

  The light intensity distribution line 74 is an example showing the distribution of the intensity of the light 3 received by the light receiving element 24 with respect to the wavelength. The spectrum calculation unit 56 calculates the light intensity distribution line 74 from the array in which the wavelength of the light 3 and the light intensity are combined. The light intensity distribution line 74 is an example in which two peaks are present. A peak at a wavelength of 400 nm or more and less than 480 nm is referred to as a fourth peak 74 a. The fourth peak 74 a is in the fifth region 68 and corresponds to the second peak 63 b of FIG. 8. Therefore, the fourth peak 74 a is detected using the second light 71. Returning to FIG. 13, the peak at a wavelength of 480 nm or more and less than 700 nm is taken as a fifth peak 74b. The fifth peak 74 b is in the third region 66 and corresponds to the third peak 63 c of FIG. 8. Therefore, the fifth peak 74 b is detected using the first light 70. Then, the spectrum calculation unit 56 displays the light intensity distribution line 74 on the display device 41 and ends the process of the spectroscopic measurement.

As described above, according to the present embodiment, the following effects are obtained.
(1) According to the present embodiment, the optical module 1 a includes the fixed reflection film 11 and the movable reflection film 13. The fixed reflection film 11 and the movable reflection film 13 are disposed to face each other. The fixed reflection film 11 and the movable reflection film 13 pass a part of the incident light 3 and reflect a part. The fixed reflection film 11 and the movable reflection film 13 are disposed at an interval of the distance 15 between the reflecting portions, and the interval changing portion 39 changes the distance 15 between the reflecting portions. And the space | interval detection part 29 detects the distance 15 between reflection parts.

  Light 3 having an inter-reflector distance 15 equal to an integral multiple of a half wavelength passes through the fixed reflection film 11 and the movable reflection film 13. The second light 71 is the first light 70 which is the light 3 whose distance 15 between the reflection portions is one half of the half wavelength of the light 3 and the second light 71 is the light 3 whose distance 15 between the reflection portions is twice the half wavelength of the light 3. is there. The light 3 passing through the fixed reflection film 11 and the movable reflection film 13 includes the first light 70 and the second light 71.

  The light receiving element 24 receives the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 and detects the intensity of the light 3. Then, the calculation unit 53 uses the intensity of the first light 70 and the intensity of the second light 71. The intensity of the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 is stronger in the first light 70 than in the second light 71. The light 3 with high intensity can measure the intensity more accurately than the weak light. Therefore, the first light 70 can measure the intensity of light more accurately than the second light 71.

  The fixed reflection film 11 and the movable reflection film 13 are caused to vibrate inherently, and the distance changer 39 changes the distance 15 between the reflection parts. At the timing at which the inter-reflecting portion distance 15 changes, there are timings at which the speed at which the inter-reflecting portion distance 15 changes is fast or late. Then, since the change of the wavelength of the passing light 3 is fast at the timing when the change speed of the inter-reflector distance 15 is fast, the variation of the measured value becomes large. At the timing when the changing speed of the inter-reflecting portion distance 15 is slow, since the change of the wavelength of the passing light 3 is slow, the variation of the measured value becomes small.

  The first light 70 and the second light 71 in the light 3 having the same wavelength are different in the distance 15 between the reflecting portions. For this reason, the timing at which the change speed of the inter-reflection portion 15 is fast differs from the timing at which the inter-reflection portion 15 changes at the timing when the inter-reflection portion distance 15 changes between the first light 70 and the second light 71 in the light 3 having the same wavelength. Therefore, when the change speed of the inter-reflecting portion distance 15 in the first light 70 is fast, the intensity of the light 3 is calculated using the second light 71 in which the change speed of the inter-reflecting portion distance 15 is slow. By this operation, the computing unit 53 can compute the intensity of the light 3 with high accuracy. As a result, the optical module 1a can output the intensity of the light 3 with respect to the wavelength of the light 3 with high accuracy.

  (2) According to the present embodiment, the calculation unit 53 uses the second light 71 to calculate the intensity of the light 3 having a wavelength of 400 nm or more and less than 480 nm. The calculator 53 uses the first light 70 to calculate the intensity of light having a wavelength of 480 nm or more and less than 700 nm. The calculator 53 calculates the intensity of the light 3 having a wavelength of 400 nm or more and less than 700 nm. The relationship between the wavelength of the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 and the intensity of the light 3 is taken as a spectrum. The computing unit 53 computes the spectrum of visible light. At this time, the calculator 53 uses the second light 71 to calculate the intensity of the light 3 having a wavelength of less than 480 nm. When the first light 70 is used to calculate the intensity of the light 3 having a wavelength of less than 480 nm, the change speed of the inter-reflecting portion distance 15 is fast. The strength of 3 can be calculated with high accuracy.

  The calculator 53 uses the first light 70 to calculate the intensity of the light 3 having a wavelength of 480 nm or more. Since the intensity of the light 3 is larger than that of the second light 71, the first light 70 can be measured accurately. When the first light 70 is used to calculate the intensity of the light 3 having a wavelength of 480 nm or more, the change speed of the inter-reflecting portion distance 15 is not fast. Therefore, the intensity of the light 3 is accurately calculated by using the first light 70. can do. As a result, the computing unit 53 can compute the intensity of the light 3 having a wavelength of 400 nm or more and less than 700 nm with high accuracy.

As described above, according to the present embodiment, the following effects are obtained.
(3) According to the present embodiment, the optical module 1 a includes the band pass filter 5. The band pass filter 5 prevents the light receiving element 24 from being irradiated with the light 3 having a wavelength of less than 400 nm and the light 3 having a wavelength of 700 nm or more. Therefore, it is possible to suppress that the light 3 of the wavelength other than the first light 70 and the second light 71 used by the calculation unit 53 affects the calculation of the spectrum.

As described above, according to the present embodiment, the following effects are obtained.
(4) According to the present embodiment, the space changer 39 includes two electrodes of the fixed electrode 12 and the movable electrode 14 facing each other. And the space | interval change part 39 applies the voltage of a rectangular wave repeatedly between the electrodes of the fixed electrode 12 and the movable electrode 14 repeatedly. By applying a voltage between the electrodes, an electrostatic force is generated between the electrodes, so the distance 15 between the reflective portions can be changed. The two opposing electrodes interlock with the fixed reflection film 11 and the movable reflection film 13. The interval changing unit 39 causes the fixed reflection film 11 and the movable reflection film 13 to vibrate uniquely by repeatedly applying a voltage. The voltage applied repeatedly between the electrodes is a rectangular wave. The rectangular wave is a waveform that can be formed with a simple circuit configuration of a single power supply and a switch circuit, so the optical module 1a can be easily manufactured.

As described above, according to the present embodiment, the following effects are obtained.
(5) According to the present embodiment, the light receiving element 24 receives the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 at the predetermined inter-reflector distance 15 a plurality of times. Since the space changer 39 causes the fixed reflection film 11 and the movable reflection film 13 to vibrate uniquely, the light receiving element 24 easily has a plurality of lights 3 passing through the fixed reflection film 11 and the movable reflection film 13 at the predetermined inter-reflection distance 15. It can be received a number of times. Then, the light receiving element 24 outputs the intensity of the received light 3 to the calculation unit 53. The calculator 53 inputs the intensity of the light 3 a plurality of times to calculate an average value. Therefore, even when the intensity of the light 3 received by the light receiving element 24 varies, the optical module 1a can output the average value. As a result, the optical module 1 a can output a value that is not easily affected by the variation in the intensity of the light 3.

As described above, according to the present embodiment, the following effects are obtained.
(6) According to the present embodiment, the spectrometer 1 includes the variable wavelength interference filter 6, the actuator driver 30, the light receiver 7, and the calculator 53. The variable wavelength interference filter 6 includes a fixed reflection film 11 and a pair of reflection films of a movable reflection film 13 and an electrostatic actuator 23. Each reflective film is disposed at an interval of the distance between reflective portions 15. And each reflection film passes a part of light 3 which injected, respectively, and reflects a part. The electrostatic actuator 23 changes the distance 15 between the reflecting portions. The interval detection unit 29 detects the inter-reflection unit distance 15, and outputs a signal indicating the interval detection unit output voltage as a gap detection signal corresponding to the detected inter-reflection unit distance 15 to the data conversion unit 28.

  Light 3 having an inter-reflector distance 15 equal to an integral multiple of a half wavelength passes through the pair of reflection films. The first light 70 is a light whose distance 15 between the reflection portions is one half of the half wavelength of the light 3 and the second light 71 is a light 3 whose distance 15 between the reflection portions is twice the half wavelength of the light. The light 3 passing through the fixed reflection film 11 and the movable reflection film 13 includes the first light 70 and the second light 71.

  The light receiving element 24 receives the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 and detects the intensity of the light 3. Then, the calculation unit 53 uses the intensity of the first light 70 and the intensity of the second light 71. The intensity of the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 is stronger in the first light 70 than in the second light 71. The light 3 with high intensity can measure the intensity more accurately than the weak light. Therefore, the first light 70 can measure the intensity of light more accurately than the second light 71.

  The fixed reflection film 11 and the movable reflection film 13 are caused to vibrate inherently, and the distance changer 39 changes the distance 15 between the reflection parts. There is a timing at which the speed at which the inter-reflecting portion distance 15 changes is fast and a timing at which the inter-reflecting portion distance 15 changes. Then, since the change of the wavelength of the passing light 3 is fast at the timing when the change speed of the inter-reflector distance 15 is fast, the variation of the measured value becomes large. At the timing when the changing speed of the inter-reflecting portion distance 15 is slow, since the change of the wavelength of the passing light 3 is slow, the variation of the measured value becomes small.

  The first light 70 and the second light 71 in the light 3 having the same wavelength are different in the distance 15 between the reflection portions. Therefore, between the first light 70 and the second light 71 in the light 3 having the same wavelength, the timing at which the changing speed of the inter-reflecting portion 15 is fast differs from the timing at which the inter-reflecting portion 15 changes. Therefore, in the first light 70, when the change speed of the inter-reflecting portion distance 15 is fast, the arithmetic unit 53 is operated by calculating the intensity of the light 3 using the second light 71 whose change speed of the inter-reflecting portion distance 15 is slow. Can calculate the intensity of the light 3 with high accuracy. As a result, the spectrometer 1 can accurately output the intensity of the light 3 with respect to the wavelength of the light 3.

As described above, according to the present embodiment, the following effects are obtained.
(7) According to the present embodiment, the optical module 1 a includes the fixed reflection film 11, the movable reflection film 13, the interval changing unit 39, the interval detection unit 29, the light receiving element 24, and the calculation unit 53. The fixed reflection film 11 and the movable reflection film 13 are disposed to face each other. The fixed reflection film 11 and the movable reflection film 13 pass a part of the incident light 3 and reflect a part. The fixed reflection film 11 and the movable reflection film 13 are disposed at a predetermined interval, and the interval changing unit 39 changes the distance 15 between the reflection units. The interval detection unit 29 detects the inter-reflection unit distance 15. The light receiving element 24 receives the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 and detects the intensity of the light 3. Then, the calculation unit 53 calculates the relationship between the wavelength of the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 and the intensity of the light 3.

  In the vibration process of step S1, the space changer 39 causes the fixed reflection film 11 and the movable reflection film 13 to vibrate uniquely to change the distance 15 between the reflection parts. Then, in the sampling step of step S3, the inter-reflection unit distance 15 detected by the interval detection unit 29 is sampled, and the intensity of the light 3 received by the light receiving element 24 is sampled. This sampling is performed at a plurality of timings within the oscillation period in which the fixed reflection film 11 and the movable reflection film 13 inherently vibrate. The light 3 passing through the fixed reflection film 11 and the movable reflection film 13 includes the first light 70 and the second light 71.

  In the spectrum calculation process of step S5, the calculation unit 53 calculates the relationship between the wavelength of the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 and the intensity of the light 3. The computing unit 53 uses the light intensity of the first light 70 and the light intensity of the second light 71. The light intensity of the light 3 passing through the fixed reflection film 11 and the movable reflection film 13 is stronger in the first light 70 than in the second light 71. The light 3 with high intensity can measure the intensity more accurately than the weak light. Therefore, the first light 70 can measure the intensity of light more accurately than the second light 71.

  At the timing at which the inter-reflecting portion distance 15 changes, there are timings at which the speed at which the inter-reflecting portion distance 15 changes is fast or late. Then, since the change of the wavelength of the passing light 3 is fast at the timing when the change speed of the inter-reflector distance 15 is fast, the variation of the measured value becomes large. At the timing when the changing speed of the inter-reflecting portion distance 15 is slow, since the change of the wavelength of the passing light 3 is slow, the variation of the measured value becomes small.

  The first light 70 and the second light 71 in the light 3 having the same wavelength are different in the distance 15 between the reflecting portions. For this reason, the timing at which the change speed of the inter-reflection portion 15 is fast differs from the timing at which the inter-reflection portion 15 changes at the timing when the inter-reflection portion distance 15 changes between the first light 70 and the second light 71 in the light 3 having the same wavelength. Therefore, when the change speed of the inter-reflecting portion distance 15 in the first light 70 is fast, the intensity of the light 3 is calculated using the second light 71 in which the change speed of the inter-reflecting portion distance 15 is slow. By this operation, the computing unit 53 can compute the intensity of the light 3 with high accuracy. As a result, the optical module 1a can output the intensity of the light 3 with respect to the wavelength of the light 3 with high accuracy.

Second Embodiment
Next, an embodiment of a gas detection apparatus provided with the above-described optical module 1a will be described using FIGS. 14 and 15. FIG. This gas detection apparatus is used, for example, as an on-vehicle gas leak detector that detects a specific gas with high sensitivity, a photoacoustic rare gas detector for breath test, or the like. Description of the same points as the above embodiment will be omitted.

  FIG. 14 is a schematic front view showing the configuration of the gas detection device, and FIG. 15 is a block diagram showing the configuration of a control system of the gas detection device. As shown in FIG. 14, the gas detection device 135 as an electronic device has a flow path 137 including a sensor chip 136, a suction port 137a, a suction flow path 137b, a discharge flow path 137c and a discharge port 137d, and a main body 138 It is a structure.

  The main body unit 138 includes a sensor unit cover 139, an ejection unit 140, and a housing 141. The flow path 137 can be attached and detached by opening and closing the sensor unit cover 139. Furthermore, the main body portion 138 includes a detection device including an optical unit 142, a filter 143, an optical module 144, a light receiving element 145 (detection unit), and the like. The optical module 1a described above is used for the optical module 144.

  Furthermore, the main body unit 138 includes a control unit 146 (processing unit) that processes the detected signal and controls the detection unit, a power supply unit 147 that supplies power, and the like. The controller 146 of the optical module 1 a is incorporated in the controller 146. The optical unit 142 includes a light source 148 for emitting the light 3, a beam splitter 149, a lens 150, a lens 151, and a lens 152. The beam splitter 149 reflects the light 3 incident from the light source 148 to the sensor chip 136 side, and transmits the light 3 incident from the sensor chip side to the light receiving element 145 side.

  As shown in FIG. 15, the gas detection device 135 is provided with an operation panel 155, a display unit 156, a connection unit 157 for interface with the outside, and a power supply unit 147. When the power supply unit 147 is a secondary battery, the connection unit 158 for charging may be provided. Further, the control unit 146 of the gas detection device 135 includes a signal processing unit 159 configured by a CPU or the like and a light source driver circuit 160 for controlling the light source 148. Further, the control unit 146 includes a wavelength control unit 161 as a control unit for controlling the optical module 144, and a light receiving circuit 162 for receiving a signal from the light receiving element 145. The wavelength control unit 161 controls the optical module 144. The wavelength controller 161 incorporates the same function as the controller 25 of the optical module 1a. Further, the control unit 146 includes a sensor chip detection circuit 164 that reads the code of the sensor chip 136 and receives a signal from the sensor chip detector 163 that detects the presence or absence of the sensor chip 136. Furthermore, the control unit 146 includes an ejection driver circuit 165 that controls the ejection unit 140 and the like.

  Next, the operation of the gas detection device 135 will be described. A sensor chip detector 163 is provided inside the sensor cover 139 at the top of the main body 138. The sensor chip detector 163 detects the presence or absence of the sensor chip 136. When detecting the detection signal from the sensor chip detector 163, the signal processing unit 159 determines that the sensor chip 136 is in a mounted state. Then, the signal processing unit 159 outputs, to the display unit 156, a display signal for displaying that the detection operation can be performed.

  Then, the operation panel 155 is operated by the operator, and an instruction signal to start detection processing is output from the operation panel 155 to the signal processing unit 159. First, the signal processing unit 159 outputs a light source driving instruction signal to the light source driver circuit 160 to operate the light source 148. When the light source 148 is driven, a stable laser beam linearly polarized at a single wavelength is emitted from the light source 148. The light source 148 incorporates a temperature sensor and a light amount sensor, and information of the sensor is output to the signal processing unit 159. When the signal processing unit 159 determines that the light source 148 is in a stable operation based on the temperature and the light amount input from the light source 148, the signal processing unit 159 controls the discharge driver circuit 165 to operate the discharge unit 140. As a result, a gas sample containing the target substance (gas molecule) to be detected is guided from the suction port 137a to the suction flow path 137b, the inside of the sensor chip 136, the discharge flow path 137c, and the discharge port 137d. In addition, the dust removal filter 137e is provided in the suction port 137a, and comparatively large dust, a part of water vapor | steam, etc. are removed.

  The sensor chip 136 is an element in which a plurality of metal nanostructures are incorporated, and is a sensor utilizing localized surface plasmon resonance. In such a sensor chip 136, a laser beam forms an enhanced electric field between metal nanostructures. When gas molecules enter the enhanced electric field, Raman scattered light and Rayleigh scattered light containing information of molecular vibration are generated. These Rayleigh scattered light and Raman scattered light pass through the optical unit 142 and enter the filter 143. The filter 143 separates the Rayleigh scattered light, and the Raman scattered light enters the light module 144.

  Then, the signal processing unit 159 outputs a control signal to the wavelength control unit 161. Thus, the wavelength control unit 161 drives the actuator of the optical module 144 to cause the optical module 144 to disperse Raman scattered light corresponding to the gas molecules to be detected. When the split light 3 is received by the light receiving element 145, a light reception signal corresponding to the amount of received light is output to the signal processing unit 159 via the light receiving circuit 162.

  The signal processing unit 159 compares the spectrum data of the Raman scattered light corresponding to the obtained gas molecule to be detected with the data stored in the ROM. Then, it is determined whether or not the gas molecule to be detected is the target gas molecule, and the substance is specified. Further, the signal processing unit 159 displays the result information on the display unit 156 and outputs the information from the connection unit 157 to the outside.

  The gas detection apparatus 135 which performs gas detection from the Raman scattered light by spectrally separating the Raman scattered light by the light module 144 is illustrated. The gas detection device 135 may be used as a gas detection device that detects the absorbance specific to the gas to specify the type of gas. In this case, the optical module 144 is used as a gas sensor that allows a gas to flow into the sensor and detects light 3 absorbed by the gas among incident light. And a gas detection apparatus is an electronic device which analyzes and discriminates the gas which flowed in in a sensor by a gas sensor. With this configuration, the gas detection device 135 can detect the component of the gas using the optical module 144.

  The gas detection device 135 includes an optical module 144 and a wavelength control unit 161 that controls the optical module 144. The wavelength control unit 161 controls the optical module 144 to control the wavelength of the light 3 transmitted by the optical module 144. The optical module 1a is used for the optical module 144. Therefore, the optical module 144 is a module that can calculate the intensity of the light 3 with respect to the wavelength of the light 3 with high accuracy. As a result, the gas detection device 135 can be a device provided with a module that can calculate the intensity of the light 3 with respect to the wavelength of the light 3 with high accuracy.

Third Embodiment
Next, an embodiment of a food analysis apparatus provided with the above-described light module 1a will be described with reference to FIG. The food analysis apparatus can be used for a noninvasive measurement apparatus of saccharides by near infrared spectroscopy, and a substance component analysis apparatus such as a noninvasive measurement apparatus of information of food, living body, minerals and the like. The food analyzer is one of the substance component analyzers. Description of the same points as the above embodiment will be omitted.

  FIG. 16 is a block diagram showing the configuration of the food analysis device. As shown in FIG. 16, the food analysis device 168 as an electronic device includes a detector 169, a control unit 170 and a display unit 171. The detector 169 includes a light source 172 for emitting the light 3, a light receiving lens 174 into which the light 3 from the measurement object 173 is introduced, and a light module 175 for separating the light 3 introduced from the light receiving lens 174. The optical module 1a described above is used for the optical module 175. Furthermore, the detector 169 includes an optical sensor 176 (detection unit) that detects the separated light.

  The control unit 170 includes a light source control unit 177 that performs on / off control of the light source 172 and brightness control at the time of lighting, and a wavelength control unit 178 as a control unit that controls the light module 175. The wavelength control unit 178 controls the optical module 175. The wavelength control unit 178 incorporates the same function as the control device 25 of the optical module 1a. Furthermore, the control unit 170 includes a detection control unit 179 that controls the light sensor 176 to obtain a spectral image received by the light sensor 176, a signal processing unit 180, and a storage unit 181.

  When the food analysis device 168 is driven, the light source control unit 177 controls the light source 172 so that the light 3 is irradiated from the light source 172 to the measurement object 173. Then, the light 3 reflected by the measurement object 173 is incident on the light module 175 through the light receiving lens 174. The optical module 175 is driven by the control of the wavelength control unit 178. Thus, light of the target wavelength can be extracted from the optical module 175 with high accuracy. Then, the extracted light 3 is received by the light sensor 176, for example. The received light 3 is accumulated in the storage unit 181 as a spectral image. Further, the signal processing unit 180 controls the wavelength control unit 178 to change the voltage value applied to the optical module 175, and acquires a spectral image for each wavelength.

  Then, the signal processing unit 180 performs arithmetic processing on data of each pixel in each image accumulated in the storage unit 181, and obtains a spectrum at each pixel. In addition, the storage unit 181 stores information on the component of the food with respect to the spectrum. The signal processing unit 180 analyzes the data of the obtained spectrum based on the information on the food stored in the storage unit 181. Then, the signal processing unit 180 obtains the food component contained in the measurement object 173 and the content of each food component. In addition, the signal processing unit 180 can also calculate food calories, freshness, and the like from the obtained food components and contents. Furthermore, by analyzing the spectral distribution in the image, the signal processing unit 180 can also carry out, for example, extraction of a portion of the food to be examined whose freshness is reduced. Furthermore, the signal processing unit 180 can also detect foreign substances and the like contained in food. Then, the signal processing unit 180 performs a process of causing the display unit 171 to display information such as the component and the content of the food to be inspected, the calorie and the freshness obtained as described above.

  The food analyzer 168 comprises a light module 175 and a wavelength controller 178 for controlling the light module 175. The wavelength control unit 178 controls the light module 175 to control the wavelength of the light 3 that the light module 175 passes. The optical module 1a is used for the optical module 175. Therefore, the optical module 175 is a module that can calculate the intensity of the light 3 with respect to the wavelength of the light 3 with high accuracy. As a result, the food analysis device 168 can be a device provided with a module that can calculate the intensity of the light 3 with respect to the wavelength of the light 3 with high accuracy.

  In addition to the food analysis device 168, it can also be used as a non-invasive measurement device for other information as described above with substantially the same configuration. For example, it can be used as a biological analysis device for analyzing biological components such as measurement and analysis of body fluid components such as blood. As such a biological analysis apparatus, for example, the food analysis apparatus 168 can be used for an apparatus for measuring a fluid component such as blood. In addition, if it is a device that detects ethyl alcohol, the food analysis device 168 can be used as a drunken driving prevention device that detects the drunk condition of the driver. Moreover, it can be used also as an electronic endoscope system provided with such a biological analysis apparatus. Furthermore, it can also be used as a mineral analyzer that performs mineral component analysis.

  Furthermore, as an electronic device using the above-described optical module 1a, the following device can be applied. For example, it is also possible to transmit data with light of each wavelength by temporally changing the intensity of light of each wavelength. In this case, light of a specific wavelength is dispersed by the above-described optical module 1a. Then, by making the light receiving unit receive the light, it is possible to extract data transmitted by the light of the specific wavelength, and thus the light of each wavelength is processed by the electronic device which extracts the data by the above optical module 1a. By doing this, optical communication with a plurality of wavelengths can be implemented. Also at this time, the electronic device can be a device provided with a module capable of calculating the intensity of the light 3 with high accuracy.

The present embodiment is not limited to the above-described embodiment, and various changes and modifications can be made by those skilled in the art within the technical concept of the present invention. A modification is described below.
(Modification 1)
In the first embodiment, a spectrum which is a distribution of the intensity of the light 3 with respect to the wavelength is calculated. The distribution of the intensity of the light 3 with respect to the frequency of the light may be calculated as a spectrum. The frequency can be calculated by dividing the velocity of light 3 by the wavelength. Therefore, by converting the wavelength into a frequency, the distribution of the intensity of the light 3 with respect to the frequency of the light can be calculated.

(Modification 2)
In the first embodiment, the electrostatic actuator 23 changes the inter-reflecting portion distance 15. Another method may be used to change the inter-reflecting portion distance 15. For example, the distance between the reflecting portions 15 may be changed using a method using an electromagnetic force such as a coil or a magnet or a piezoelectric element.

(Modification 3)
In the first embodiment, assuming that the second integer is 2 and the first integer is 1, the computing unit 53 calculates the first light 70 in which the inter-reflection portion distance 15 is a first integer multiple of the half wavelength of the light 3. The intensity and the intensity of the second light 71 whose distance between the reflection portions 15 is the second integer multiple of the half wavelength of the light 3 were used. The second integer may be an integer larger than the first integer. When the first integer is 1, the second integer may be an integer of 2 or more. Further, the first integer may be 2 and the second integer may be 3 or more. At this time, it is preferable to suppress the progress of the light 3 of the unnecessary wavelength by changing the characteristics of the band pass filter 5.

(Modification 4)
In the first embodiment, the actuator drive unit 30 repetitively applies a rectangular wave voltage between the fixed electrode 12 and the movable electrode 14. When the actuator drive unit 30 can easily output a waveform other than a rectangular wave, it may not be a rectangular wave. It may be a waveform that is easy to output. For example, a sine wave or a triangular wave may be used.

(Modification 5)
In the first embodiment, the average value calculation unit 55 calculates the average value after performing the interpolation calculation in the averaging process of step S4. The average value calculation unit 55 may perform interpolation calculation after calculating the average value.

(Modification 6)
In the first embodiment, the spectrum calculation unit 56 uses the second light 71 to calculate the intensity of the light 3 having a wavelength of 400 nm or more and less than 480 nm, and calculates the intensity of the light having a wavelength of 480 nm or more and less than 700 nm. One light 70 was used. When the drive conditions of the variable wavelength interference filter 6 are different, the range of wavelengths for selectively using the first light 70 and the second light 71 may be changed. The intensity of the light 3 can be calculated with high accuracy by setting the optimum conditions.

(Modification 7)
In the first embodiment, the band pass filter 5 is disposed between the DUT 2 and the variable wavelength interference filter 6. The band pass filter 5 may be disposed between the variable wavelength interference filter 6 and the light receiver 7. Also at this time, the band pass filter 5 can suppress that the light having a wavelength of less than 400 nm and the light having a wavelength of 700 nm or more are irradiated to the light receiver 7.

  DESCRIPTION OF SYMBOLS 1a, 144, 175 ... Optical module, 1: ... Spectrometer, 5 ... Band pass filter, 6: ... Wavelength variable interference filter, 7: ... Photodetector as a light receiving part, 11 ... Fixed reflection as a 1st reflective part and a reflecting film Film 12 fixed electrode as electrode 13 movable reflecting film as second reflecting portion and reflecting film 14 movable electrode as electrode 15 distance between reflecting portions as gap amount 23 electrostatic actuator 24: light receiving element, 29: interval detecting unit as gap detecting unit, 30: actuator driving unit as filter driving unit, 39: interval changing unit, 53: computing unit, 70: first light, 71: second light, 135: Gas detection device as an electronic device, 168: food analysis device as an electronic device.

Claims (8)

A first reflecting portion that passes part of incident light and reflects part;
A second reflection part disposed opposite to the first reflection part, which transmits a part of incident light and reflects a part;
An interval changing unit that causes the first reflection unit and the second reflection unit to perform natural oscillation to change the distance between the reflection units, which is the interval between the first reflection unit and the second reflection unit;
An interval detection unit that detects the distance between the reflection units;
A light receiving element that receives light passing through the first reflecting portion and the second reflecting portion and detects the intensity of the light;
An arithmetic unit that calculates the relationship between the wavelength of light passing through the first reflection unit and the second reflection unit and the intensity of the light;
When the second integer is an integer larger than the first integer,
The calculation unit may be configured to generate an intensity of the first light whose distance between the reflection portions is the first integer multiple of a half wavelength of light, and a second distance whose distance between the reflection portions is the second integer multiple of the light half wavelength. An optical module characterized by using light intensity. The optical module according to claim 1, wherein
The calculation unit uses the second light to calculate the intensity of light with a wavelength of 400 nm or more and less than 480 nm, and uses the first light to calculate the intensity of light with a wavelength of 480 nm or more and less than 700 nm. An optical module comprising: calculating a relationship between a wavelength of light passing through a reflecting portion and the second reflecting portion and an intensity of the light. The optical module according to claim 1 or 2, wherein
What is claimed is: 1. An optical module comprising: a band pass filter for suppressing the light receiving element from being irradiated with light having a wavelength of less than 400 nm and light having a wavelength of 700 nm or more. An optical module according to any one of claims 1 to 3, wherein
The optical module according to claim 1, wherein the gap changing unit comprises two electrodes interlockingly opposed to the first reflecting unit and the second reflecting unit, and repeatedly applying a rectangular wave voltage between the electrodes. The optical module according to claim 4, wherein
The light is characterized in that the arithmetic unit inputs the light intensity of the light passing through the first reflecting portion and the second reflecting portion at a predetermined distance between the reflecting portions a plurality of times from the light receiving element to calculate an average value. module. A variable wavelength interference filter having a pair of reflective films, and an electrostatic actuator that changes a gap amount that is a distance between the pair of reflective films;
A filter drive unit that applies a periodic drive voltage to the electrostatic actuator;
A gap detection unit that detects the gap amount and outputs a gap detection signal corresponding to the detected gap amount;
A light receiving unit that receives the light output from the variable wavelength interference filter and outputs a light intensity detection signal corresponding to the intensity of the received light;
And an operation unit that calculates the relationship between the wavelength of light passing through the variable wavelength interference filter and the intensity of the light.
When the second integer is an integer larger than the first integer,
The calculation unit is configured to calculate the intensity of the first light whose gap amount is the first integer multiple of the half wavelength of light, and the intensity of the second light whose gap amount is the second integer multiple of the light half wavelength. And using.   An electronic device comprising the optical module according to any one of claims 1 to 5. A first reflecting portion that passes a part of incident light and reflects a part;
A second reflection part disposed opposite to the first reflection part, which transmits a part of incident light and reflects a part;
An interval changing unit that causes the first reflection unit and the second reflection unit to perform natural oscillation to change the distance between the reflection units, which is the interval between the first reflection unit and the second reflection unit;
An interval detection unit that detects the distance between the reflection units;
A light receiving element that receives light passing through the first reflecting portion and the second reflecting portion and detects the intensity of the light;
A spectroscopic measurement method using an optical module, comprising: an operation unit that calculates the relationship between the wavelength of light passing through the first reflection unit and the second reflection unit and the intensity of the light,
A vibration step of causing the first reflection portion and the second reflection portion to inherently vibrate;
A sampling step of sampling the distance between the reflection portions and the intensity of light received by the light receiving element at a plurality of timings within a vibration cycle in which the first reflection portion and the second reflection portion inherently vibrate;
When the second integer is an integer larger than the first integer,
The computing unit is configured to generate an intensity of the first light whose distance between the reflecting portions is the first integer multiple of a half wavelength of light, and a second distance whose distance between the reflecting portions is the second integer multiple of the half wavelength of light A spectrum calculation step of calculating the relationship between the wavelength of light passing through the first reflection part and the second reflection part and the light intensity using the light intensity; .

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