JP2011080952A - Distance measuring device, method of measuring distance, distance measurement program, and computer-readable recording medium - Google Patents

Abstract

A distance measuring device that measures the distance between the tip of a probe and the surface of the workpiece from the positional relationship between the secondary image of the probe generated on the workpiece surface and the tip of the probe.
An edge specifying unit 101 for specifying an edge of a probe 6 in an image obtained by capturing a secondary image appearing on the surface of a workpiece 9 by irradiating light from the LED lamp 7 to the probe 6 and the probe 6; A straight line insertion unit 102 that inserts a straight line along the outer edge of the next image on the image; and an overlap determination unit 103 that determines an overlap between the edge and the straight line. One or more LED lamps 7, an imaging device, The probe 6 is held so as to be movable integrally with the surface of the workpiece 9. Therefore, the distance measuring apparatus 100 can measure the distance between the edge of the probe 6 and the surface of the work 9 from the positional relationship between the secondary image of the probe 6 generated on the surface of the work 9 and the edge of the probe 6. it can.
[Selection] Figure 1

Description

  The present invention generates a secondary image of the probe on the workpiece surface, and can measure the distance between the tip of the probe and the workpiece surface from the positional relationship between the secondary image and the tip of the probe. The present invention relates to a measurement apparatus, a distance measurement method, a distance measurement program, and a computer-readable recording medium.

  2. Description of the Related Art Conventionally, there are known devices such as a dispenser that carries an image processing device and performs a coating operation while correcting the position of a workpiece, and a microscope that expands and detects the distribution state of compound groups scattered in an analysis sample. .

  In these devices, for example, when applying a fluid sample to the workpiece surface, it is necessary to control the application position and amount of the fluid sample, so the distance between the probe tip and the workpiece surface must be accurately controlled. There is.

  The sampling system described in US Pat. No. 6,057,017 is intended to obtain a sample from at least one point of the surface array for subsequent analysis, and an image to control the distance between the probe and the surface array. Analytical methods are used.

  More specifically, the sampling system includes a light source, a camera, and an image processing device. The light source is disposed adjacent to the tip of the probe, and irradiates a beam of light toward the tip of the probe so that the shadow of the tip of the probe falls on the surface array. The camera is provided for acquiring an image of the tip of the probe and an image of a shadow appearing on the surface array by irradiating the probe with light from the light source. The image processing device applies an average line brightness (LAB) to the image captured by the camera to determine the actual distance between the probe tip and the surface array.

  That is, in the sampling system, the light source emits a light beam toward the probe, and the camera captures a continuous image of the tip of the probe and the surface array, more specifically, the probe that is dropped onto the surface array. Capture the shadow of the tip. Then, the image processing apparatus binarizes the captured shadow image by luminance. At this time, since the LAB indicating the probe tip and the surface array has the lowest luminance, the image processing apparatus calculates the distance between the two horizontal lines that are the lowest LAB between the probe tip and the surface array. Measure as distance. Then, the sampling system controls the distance between the tip of the probe and the surface array by moving the stage on which the surface array is placed based on the measured distance.

  The fractionation device described in Patent Document 2 is for measuring the distance between the probe and the sample plate in order to keep the distance between the sample plate and the tip of the probe constant when droplets are dropped onto the sample plate. Proximity sensor is provided on the side of the probe. The sample plate is mounted on the stage and moves in the vertical and horizontal directions. The stage is connected to a control device, and the control device controls the movement of the stage. The control device feedback-controls the stage so that the measured value of the proximity sensor becomes the set value, and moves the sample plate upward when dropping a droplet from the probe, so that the distance between the probe and the sample plate is increased. Fractionation is performed by bringing the droplets close to each other and contacting the sample plate.

JP 2008-542752 A (published on November 27, 2008) Japanese Patent Laying-Open No. 2005-98766 (released on April 14, 2005)

  However, the techniques described in Patent Documents 1 and 2 have the following problems.

  In the sample collection system described in Patent Document 1, the shadow of the probe is used to measure the distance between the tip of the probe and the surface array. This point is the same as the distance measuring device according to the present invention described later. Common.

  However, since the sampling system uses line average luminance (LAB) technology to measure the distance between the probe and the surface array, it is necessary to make the width of the probe shadow on the surface array as narrow as possible. is there. To make this possible, the angle of the camera relative to the probe needs to be as large as possible. On the other hand, when the camera angle is increased in this way, it becomes difficult to observe changes on the surface. In particular, when the sample is applied in the state of a small point, the area of the point to be observed becomes extremely small, and even when the image magnification is small, even the presence of the point may not be grasped.

  Thus, in the image analysis method using the LAB technique, setting of the camera angle with respect to the probe is extremely important. On the other hand, Patent Document 1 does not mention at all how to set the angle of the camera with respect to the probe. In addition, the sampling system described in Patent Document 1 uses a probe having a tip outer diameter of 635 μm (see paragraph [0044] of the specification), and uses a probe having such a thick tip diameter, It is also difficult to make the width of the probe shadow generated on the surface array as small as possible. In addition, with such a probe having a large outer diameter, it becomes more difficult to capture a shadow with the camera as the probe approaches the tip of the probe. Therefore, it is unclear for those skilled in the art how to solve the problem described in Patent Document 1 using the technique disclosed in Patent Document 1.

  There are also problems specific to LAB technology. That is, the sample collection system described in Patent Document 1 measures the distance between the tip of the probe and the surface array using a shadow appearing at the tip of the probe. However, depending on the type of workpiece surface, a specular phenomenon occurs at the tip of the probe as shown in FIG. In addition, when the workpiece surface is white, the tip portion may become white, and the tip of the probe may not be shaded. Similarly, the shadow of the probe cannot be generated on the workpiece surface depending on the state of the workpiece surface (material (silicon, glass, etc.), color, surface roughness, etc.) and the position / angle of the light source with respect to the probe. Therefore, since the sample collection system of Patent Document 1 uses the LAB technology, there is a problem in that it is subject to restrictions such as the state of the workpiece surface (material, color, surface roughness, etc.) and the position and angle of the light source with respect to the probe. .

  Furthermore, the sample collection system moves a stage on which the surface array is placed in order to control the distance between the tip of the probe and the surface array. That is, the sampling system does not employ a method in which the probe moves with respect to the stage. Therefore, the work area is inevitably small, and when there is an inclination on the surface of the work area, it is difficult to control the distance between the tip of the probe and the surface array. Therefore, the sample collection system described in Patent Document 1 cannot be used for coating work on a device having a large work area such as a large liquid crystal device.

  As described above, the sample collection system described in Patent Document 1 has the above-described various problems, and thus is not a highly usable system for the user.

  On the other hand, the sample collection system described in Patent Document 2 controls the distance between the tip of the probe and the surface array using a proximity sensor. Therefore, the distance measuring method is originally different from the distance measuring apparatus according to the present invention that controls the distance using a secondary image.

  Also, when measuring the distance between the probe tip and the surface array using a proximity sensor, it is necessary to determine in advance the relationship between the probe tip and the surface array before measurement. It was hard work. In addition, since the workpiece surface is not necessarily supported horizontally, the distance measured at a certain point is not always applied at other positions, and the measurement results are not stable. there were.

  Note that the sample collection system described in Patent Document 2 employs a method of moving the sample plate upward in order to make the distance between the probe and the sample plate closer. The distance between the probe tip and the sample plate is described as 0.6 mm (paragraph [0012] of the specification). Based on such disclosure of Patent Document 2, and considering that Patent Document 2 does not disclose a detailed description of the attachment position and the like of the proximity sensor, the sampling system includes the tip of the probe. It is not intended to bring the distance between the plate and the sample plate closer to the order of several tens of microns, and it cannot be said that it is designed as such.

  The present invention has been made in view of the above problems, and its purpose is to determine the relationship between the tip of the probe and the workpiece surface from the positional relationship between the secondary image of the probe generated on the workpiece surface and the tip of the probe. A distance measuring device, a distance measuring device method, a distance measuring program, and a computer-readable recording medium are provided.

In order to solve the above problems, a distance measuring device according to the present invention provides
A secondary image that appears on the workpiece surface by irradiating the probe with light from the light source and the probe are picked up by the imaging device, and the distance between the tip of the probe and the workpiece surface using the image captured by the imaging device In a distance measuring device for measuring
Specifying means for specifying the tip in the image;
Insertion means for inserting a straight line along the outer edge of the secondary image in the image onto the image;
Determining means for determining an overlap between the tip portion specified by the specifying means and the straight line inserted by the insertion means;
One or more of the light sources, the imaging device, and the probe are held movably integrally with the workpiece surface.

In addition, the distance measuring method according to the present invention is to solve the above problems,
A secondary image that appears on the workpiece surface by irradiating the probe with light from the light source and the probe are picked up by the imaging device, and the distance between the tip of the probe and the workpiece surface using the image captured by the imaging device A distance measuring method for measuring
A specifying step of specifying the tip in the image;
An insertion step of inserting a straight line along the outer edge of the secondary image in the image onto the image;
A determination step of determining an overlap between the tip portion specified in the specifying step and the straight line inserted in the insertion step.

  According to the above configuration, the specifying unit (specifying step) specifies the tip of the probe in the probe secondary image and the probe image appearing on the workpiece surface imaged by the imaging device. The inserting means inserts a straight line along the outer edge of the secondary image in the image. And a determination means determines the overlap with the said front-end | tip part which the specific means (specific step) specified, and the said straight line which the insertion means inserted.

  In other words, the distance measuring device (distance measuring method) according to the present invention is configured such that, as the probe and the workpiece surface are closer, the straight line inserted along the outer edge of the tip and the secondary image on the image. When the probe approaches and the surface of the workpiece comes into contact, the property that the tip and the straight line overlap on the image is used. Therefore, when the determination means determines that the tip portion and the straight line overlap, the contact between the probe and the workpiece surface can be confirmed.

  Therefore, the distance measuring device (distance measuring method) according to the present invention considers that the probe and the workpiece surface are in contact with each other when the tip and the straight line overlap each other, and moves the probe based on that point. The distance between the tip and the workpiece surface can be measured based on the amount and the moving direction.

  Further, as described above, the distance measuring device (distance measuring method) according to the present invention generates a secondary image of the probe on the workpiece surface, and the tip portion and the second portion specified by the specifying means (specifying step). The distance between the tip and the workpiece surface is measured from the positional relationship with the straight line inserted along the outer edge of the next image.

  Therefore, the distance measuring device (distance measuring method) according to the present invention is different from the image analysis method using the LAB technique, and the distance between the tip and the workpiece surface is not affected by the size of the probe diameter. Can be measured.

  Furthermore, in the distance measuring device according to the present invention, one or more of the light sources, the imaging device, and the probe are configured to be held so as to be integrally movable with respect to the workpiece surface.

  Thereby, since the positional relationship between the one or more light sources, the imaging device, and the probe is maintained in a fixed state, the position of the probe moves for each measurement in the image to be captured, and thereby the measurement result It is also possible to avoid a situation in which variations occur, and to provide a more stable measurement result to the user. Moreover, because of the measurement method, even when the shape of the workpiece surface is not stable (for example, when the workpiece surface is inclined), the distance between the tip portion and the workpiece surface can be measured.

  In addition, since the one or more light sources, the imaging device, and the probe are held so as to be integrally movable with respect to the work surface, the distance measuring device (distance measuring method) according to the present invention The work area on the surface is not limited, and it is possible to handle a huge workpiece surface. In other words, in the conventional sample coating apparatus, the workpiece surface side is controlled so as to be movable, so depending on the shape of the workpiece surface, etc., it is not possible to apply multiple samples to the same workpiece surface using multiple probes. It was difficult. On the other hand, when the distance measuring apparatus according to the present invention is applied to a sample coating apparatus, a plurality of different samples can be coated on the same workpiece surface in a short time. Therefore, by using the distance measuring device (distance measuring method) according to the present invention, a significant productivity improvement can be brought to the user.

Furthermore, in the distance measuring device according to the present invention,
It is preferable that calculation means is provided for calculating a distance between the tip portion and the workpiece surface based on a distance from the tip portion specified by the specifying means to the straight line inserted by the insertion means.

  As described above, in the distance measuring device according to the present invention, the specifying unit specifies the tip of the probe in the probe secondary image and the probe image appearing on the workpiece surface imaged by the imaging device. The inserting means inserts a straight line along the outer edge of the secondary image in the image. Further, in the distance measuring device according to the present invention, the calculating means includes the tip portion and the workpiece surface based on the distance from the tip portion specified by the specifying means to the straight line inserted by the insertion means. The distance is calculated.

  Specifically, for example, by calculating in advance a correlation between the actual distance between the tip and the workpiece surface and the distance from the tip to the straight line inserted by the insertion means, the calculation means Can calculate the distance between the tip and the workpiece surface based on the distance from the tip to the straight line. Thereby, the structure by which the distance of the said front-end | tip part and the said workpiece | work surface is calculated automatically is realizable.

  Here, the distance from the tip to the straight line is the intersection of the straight line passing through the tip and extending in the longitudinal direction of the probe in the image and the straight line inserted by the insertion means, and the tip. The distance between.

Furthermore, in the distance measuring device according to the present invention,
The secondary image is preferably a shadow of the probe or a reflection image of the probe.

  According to the above configuration, in the distance measuring device according to the present invention, it is possible to cope with the secondary image that is either the shadow of the probe or the reflected image of the probe. That is, the distance measuring device according to the present invention can measure the distance between the tip and the workpiece surface even when a reflected image of the probe is generated instead of the shadow of the probe due to the material of the workpiece surface or the like. .

Furthermore, in the distance measuring device according to the present invention,
It is preferable that a plurality of the light sources exist.

  According to the above configuration, the distance measuring device according to the present invention includes a plurality of light sources that irradiate the probe with light. Thereby, since light is irradiated with respect to the probe from a plurality of directions, the imaging device can clearly capture the shape of the tip of the probe. As a result, the distance measuring device according to the present invention can measure the distance between the tip of the probe and the workpiece surface more accurately.

  In addition, it turns out that the said structure is effective also from the characteristic that a reflected image generate | occur | produces on a workpiece | work surface more clearly by irradiating light from a several direction with respect to a probe.

Furthermore, in the distance measuring device according to the present invention,
The light source is in a region in a range of 45 ° with respect to the imaging device side and the opposite side from an axis perpendicular to the imaging direction of the imaging device through the center of the probe in plan view. It is preferable that they are arranged.

Furthermore, in the distance measuring device according to the present invention,
The light source is in a region within a range of 30 ° to 60 ° with respect to the imaging device side from an axis orthogonal to the imaging direction of the imaging device through the center of the probe in plan view. It is preferable that they are arranged.

  With the above configuration, the imaging apparatus can more clearly capture the secondary image of the probe generated on the workpiece surface, and can measure the distance between the tip of the probe and the workpiece surface more accurately.

Furthermore, in the distance measuring device according to the present invention,
The imaging device is preferably arranged in a region where the imaging direction is in the range of 40 ° to 80 °, preferably 50 ° to 65 ° with respect to the probe.

  With the above configuration, the secondary image of the probe generated on the workpiece surface can be captured more clearly, and the distance between the tip of the probe and the workpiece surface can be measured more accurately.

  The distance measuring device may be realized by a computer. In this case, the distance measuring program for causing the distance measuring device to be realized by the computer by operating the computer as each of the means, and the program are recorded. Computer-readable recording media are also within the scope of the present invention.

  As described above, the distance measuring device according to the present invention includes a specifying unit that specifies the tip portion in the image, and an insertion unit that inserts a straight line along the outer edge of the secondary image in the image onto the image. Calculating means for calculating a distance between the tip portion and the work surface based on a distance from the tip portion specified by the specifying means to the straight line inserted by the insertion means. In this configuration, the light source, the imaging device, and the probe are held so as to be integrally movable with respect to the workpiece surface.

  In addition, the distance measuring method according to the present invention includes, as described above, a specifying step for specifying the tip in the image, and an insertion for inserting a straight line along the outer edge of the secondary image in the image onto the image. And a determination step for determining an overlap between the tip portion specified in the specifying step and the straight line inserted in the insertion step.

  Therefore, it is possible to measure the distance between the probe tip and the workpiece surface from the positional relationship between the probe secondary image generated on the workpiece surface and the probe tip.

It is a block diagram which shows schematic structure of the distance calculation apparatus which concerns on this invention. It is a figure which shows schematic structure of the sample coating device with which the distance measuring device which concerns on this invention was integrated. It is a figure which shows the example of a straight line insertion by a straight line insertion part, and is an image which shows a mode that the 1st-3rd straight line was inserted in the state whose distance between the edge of a probe and the surface of a workpiece | work is 0 micrometer. It is a figure which shows the example of a straight line insertion by a straight line insertion part, and is an image which shows a mode that the 1st-3rd straight line was inserted in the state whose distance between the edge of a probe and the surface of a workpiece | work is 50 micrometers. It is a figure which shows the example of a straight line insertion by a straight line insertion part, and is an image which shows a mode that the 1st-3rd straight line was inserted in the state whose distance between the edge of a probe and the surface of a workpiece | work is 100 micrometers. It is a figure which shows a mode that the 1st-3rd straight line was inserted in the state whose distance between the edge of a probe and the surface of a workpiece | work is 100 micrometers, and two shadows appeared using two LED lamps It is an image which shows the example of a case. When a reflection image of the probe is generated on the surface of the silicon workpiece, the image shows a case where the distance between the probe edge and the workpiece surface is 0 μm, and (a) shows the case where one LED lamp is used. (B) is an image showing a case where a plurality of LED lamps are used. When a reflection image of the probe is generated on the surface of the silicon workpiece, the image shows a case where the distance between the probe edge and the workpiece surface is 50 μm, and (a) shows the case where one LED lamp is used. (B) is an image showing a case where a plurality of LED lamps are used. When a reflection image of the probe 6 is generated on the surface of the ITO plate, it is an image showing a case where the distance between the edge of the probe 6 and the surface of the ITO plate is 0 μm, and (a) uses one LED lamp. (B) is an image showing a case where a plurality of LED lamps are used. When a reflection image of the probe 6 is generated on the surface of the ITO plate, it is an image showing a case where the distance between the edge of the probe 6 and the surface of the ITO plate is 50 μm, and (a) uses one LED lamp. (B) is an image showing a case where a plurality of LED lamps are used. When the angle of the imaging direction of the CCD camera with respect to the probe is set to 75 °, it is an image in which a shadow and a probe appearing on the surface of the workpiece imaged by the CCD camera are imaged, and (a) to (c) are respectively probes. It is an image when the distance between the edge of this and the surface of a workpiece | work is 0 micrometer, 50 micrometers, and 100 micrometers. When the angle of the imaging direction of the CCD camera with respect to the probe is set to 70 °, it is an image in which a shadow and a probe appearing on the surface of the work imaged by the CCD camera are imaged, and (a) to (c) are respectively probes. It is an image when the distance between the edge of this and the surface of a workpiece | work is 0 micrometer, 50 micrometers, and 100 micrometers. When the angle of the imaging direction of the CCD camera with respect to the probe is set to 60 °, it is an image in which the shadow and the probe appearing on the surface of the workpiece imaged by the CCD camera are imaged, and (a) to (c) are the probes. It is an image when the distance between the edge of this and the surface of a workpiece | work is 0 micrometer, 50 micrometers, and 100 micrometers. When the angle of the imaging direction of the CCD camera with respect to the probe is set to 45 °, it is an image in which the shadow and the probe appearing on the surface of the workpiece imaged by the CCD camera are imaged, and (a) to (c) are respectively probes. It is an image when the distance between the edge of this and the surface of a workpiece | work is 0 micrometer, 50 micrometers, and 100 micrometers. It is an image which shows the mode of the sample coating device when the angle of the imaging direction of the CCD camera with respect to the probe is set to 75 °. It is an image which shows the mode of the sample coating device when the angle of the imaging direction of the CCD camera with respect to the probe is set to 60 °. It is an image which shows the mode of the sample application | coating apparatus when the angle of the imaging direction of the CCD camera with respect to a probe is set to 45 degrees. When the angle in the imaging direction of the CCD camera with respect to the probe 6 is set to 75 °, the shadow and the probe appear on the surface of the workpiece imaged by the CCD camera, and (a) to (e) are respectively images. The direction in which the irradiation direction of the LED lamp 7 irradiating toward the center of the probe 6 is rotated about 110 ° to the left in plan view with respect to the imaging direction of the CCD camera 3, the direction rotated about 25 ° to the left, and the right This is an image when set in a direction rotated about 30 °, a direction rotated about 75 ° to the right, and a direction rotated about 60 ° to the left. When the angle of the imaging direction of the CCD camera with respect to the probe 6 is set to 60 °, it is an image in which a shadow and a probe appearing on the surface of the workpiece imaged by the CCD camera are imaged, and (a) to (e) are respectively The direction in which the LED lamp 7 that irradiates toward the center of the probe 6 is rotated about 130 ° to the left in plan view with respect to the imaging direction of the CCD camera 3, the direction rotated about 25 ° to the left, and the right The image is set in a direction rotated about 25 °, a direction rotated about 80 ° to the right, and a direction rotated about 60 ° to the left. When the angle of the imaging direction of the CCD camera with respect to the probe 6 is set to 45 °, it is an image in which the shadow and the probe appearing on the surface of the workpiece imaged by the CCD camera are imaged, and (a) to (e) are respectively The direction in which the LED lamp 7 that irradiates toward the center of the probe 6 is rotated about 130 ° to the left in plan view with respect to the imaging direction of the CCD camera 3, the direction rotated about 25 ° to the left, and the right The image is set in a direction rotated about 25 °, a direction rotated about 80 ° to the right, and a direction rotated about 60 ° to the left. It is a figure which shows schematic structure of the cutting device with which the distance measuring device which concerns on this invention was integrated. It is an image for demonstrating that the mirror surface phenomenon in a front-end | tip part is prevented by coating a probe with a fluorine-type material. It is an image which shows a mode that a specular phenomenon generate | occur | produces in the front-end | tip part of a probe.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. For convenience of explanation, members having the same functions as those shown in the drawings are denoted by the same reference numerals, and description thereof is omitted.

  The distance measuring apparatus 100 according to the present invention will be briefly described as follows. That is, referring to FIGS. 1 and 2, the distance measuring apparatus 100 captures a secondary image that appears on the surface of the work 9 and the probe 6 by irradiating the probe 6 with light from the LED lamp (light source) 7. , An edge specifying part (specifying means) 101 for specifying the edge of the probe 6, a straight line inserting part (inserting means) 102 for inserting a straight line along the outer edge of the secondary image in the image, and an edge specifying An overlap determination unit (determination unit) 103 that determines an overlap between the edge specified by the unit 101 and the straight line inserted by the straight line insertion unit 102, and includes one or more LED lamps 7, a CCD camera 3, and a probe 6 Is configured to be movable integrally with the surface of the workpiece 9.

  Thereby, the distance measuring apparatus 100 measures the distance between the tip of the probe 6 and the surface of the workpiece 9 from the positional relationship between the secondary image of the probe 6 generated on the surface of the workpiece 9 and the tip of the probe 6. be able to.

  Hereinafter, the configuration of the distance measuring apparatus 100 and the configuration of the sample coating apparatus 50 including the distance measuring apparatus 100 will be described. For convenience of explanation, the configuration of the sample coating apparatus 50 will be described.

[Configuration of Sample Coating Apparatus 50]
FIG. 2 is a diagram showing a schematic configuration of the sample coating apparatus 50.

  As shown in the figure, the sample coating apparatus 50 includes a lens 1, an extension tube 2, a CCD camera 3, a USB video capture 4, a personal computer 5, a probe 6, an LED lamp 7, and an LED illumination power supply 8. And a workpiece 9, a workpiece stage 10, a minute amount coating device 11, a moving device 12, and a holding unit 13.

  The lens 1 irradiates the probe 6 with light from the LED lamp 7 to form a secondary image (shadow or reflected image) appearing on the surface of the work 9 and the probe 6 as a subject of the CCD camera 3. The subject is imaged. In this embodiment, the lens 1 uses a super micro camera lens QT3515 manufactured by Elmo Co., Ltd. The super micro camera lens QT3515 has a focal length f = 15 mm, a maximum aperture ratio of 1: 3.5, and an angle of view of 9 ° or less. Therefore, the lens is characterized in that the object to be photographed can be captured in such a manner that the object to be photographed is pinpointed, that is, only the vicinity of the location targeted as the object to be imaged is displayed on the display device 60.

  The extension tubes 2 are provided for enlarging the subject image captured by the lens 1, and 2 to 4 extension tubes 2 are attached between the lens 1 and the CCD camera 3. The extension tube 2 has an effect of enlarging the subject image to 25 to 30 times by attaching two, 50 to 60 times by attaching three, and 100 to 120 times by attaching four.

  The CCD camera 3 captures a secondary image (shadow or reflected image) appearing on the surface of the work 9 and the probe 6 by irradiating the probe 6 with light from the LED lamp 7 via the lens 1 and the extension tube 2. And includes a camera body 3a and a camera amplifier 3b. In the present embodiment, a microview AS-807SP manufactured by ARS Co., Ltd. is used as the CCD camera 3. The micro view AS-807SP has a head outer diameter of 7 mm, a head length of 41 mm, an NTSC / PAL system, a 1/6 inch CCD solid element, and an effective pixel of 380,000 pixels. The CCD camera 3 may be realized by a configuration including the lens 1 and the extension tube 2 as a part thereof.

  The USB video capture 4 is used to capture an image acquired from the camera amplifier 3b into the personal computer 5 as digital data. In this embodiment, the AD-VD0303 manufactured by Alpha Data Co., Ltd. is used. ing.

  The personal computer 5 captures a digitized image from the USB video capture 4. In this embodiment, VideoStudio 7 SE Basic manufactured by ULEAD Co., Ltd. is used as image capturing software. The personal computer 5 is also used for measuring the distance between the tip of the probe 6 and the surface of the work 9. The configuration and method for measuring the distance will be described later.

  The probe 6 drops a sample supplied from the micro-coating device 11 onto the surface of the work 9 from its tip, and is a microsyringe needle, a cemented carbide needle, a tungsten needle, or a micro drill (Nisshin). Tool Co., Ltd.) is used.

  The LED lamp 7 is for generating a secondary image (shadow or reflected image) on the surface of the work 9 by irradiating the probe 6 with light. In this embodiment, the LED lamp 7 is a high-intensity LED (round, φ5 mm). , Single color, blue-green). Since green and blue-green LED lamps provide a greater luminous intensity than other color LED lamps, they can be suitably used in the sample coating apparatus 50. The directivity angle can be selected from 15 °, 30 °, 60 °, and the like.

  However, the LED lamp 7 is not limited to a green or blue-green lamp, and it is of course possible to use lamps of other colors such as white. The directivity angle is not limited to the above angle, and can be selected from various angles. One or a plurality of LED illumination power supplies 8 are provided.

  The LED illumination power supply 8 is used to supply power to the LED lamp 7, and in this embodiment, a pulse dimming power supply IDPW-30M8V manufactured by Immac Co., Ltd. is used. The pulse dimming power supply IDPW-30M8V is an eight-circuit independent circuit.

  The workpiece 9 is for collecting a sample dropped from the probe 6.

  The workpiece stage 10 has a workpiece 9 mounted on the upper part and connected to a Y-axis actuator 12b described later at the lower part. Then, the workpiece stage 10 moves the workpiece 9 in the Y-axis direction as the Y-axis actuator 12b is driven.

  The minute amount coating apparatus 11 supplies a predetermined amount of sample to the probe 6, and the sample is dropped from the tip of the probe 6 onto the surface of the work 9. In the present embodiment, a very small amount dispenser SMP-3 manufactured by Musashi Engineering Co., Ltd. is used, and this apparatus can discharge a very small amount of sample of 1 nL by a volume measuring method.

  The moving device 12 controls the positioning of the dropping position in a three-dimensional direction when a sample is applied from the probe 6 to the workpiece 9, and in this embodiment, a SHOT mini 200S manufactured by Musashi Engineering Co., Ltd. is used. is doing.

  The moving device 12 includes an X-axis actuator 12a, a Y-axis actuator 12b, a Z-axis actuator 12c, and a drive control unit 12d. The X-axis actuator 12a, the Y-axis actuator 12b (using a stepping motor), and the Z-axis actuator 12c respectively show the positional relationship between the probe 6 and the workpiece 9 in the X direction, Y direction, and Z direction (up and down directions in FIG. 2). Direction). The drive control unit 12d is for controlling the drive of the moving device 12, and a commercially available coating program (MuPRO ver.1.0 manufactured by Musashi Engineering Co., Ltd.) is installed.

  The holding unit 13 holds the camera body 3 a and the LED lamp 7. The holding unit 13 is fixed to the sample coating device 50 so as to be interlocked with the operation of the probe 6 in the XYZ directions. As a result, a state is formed in which the camera body 3a, the LED lamp 7, and the probe 6 are held so as to be movable integrally with the surface of the workpiece 9. The holding unit 13 is realized by a configuration that can appropriately adjust the angle of the CCD camera 3 or the LED lamp 7 with respect to the probe 6 or the positional relationship between the CCD camera 3 and the LED lamp 7. As long as the camera body 3a, the LED lamp 7, and the probe 6 are held so as to be integrally movable with respect to the surface of the workpiece 9, the holding unit 13 may be realized in any configuration.

[Configuration of Distance Measuring Device 100]
Next, details of the distance measuring apparatus 100 will be described with reference to FIG. FIG. 1 is a block diagram illustrating a schematic configuration of the distance measuring apparatus 100.

  The personal computer 5 includes a control unit 40. The control unit 40 can be realized by a CPU (central processing unit) reading a program stored in a storage device such as a ROM (read only memory) (not shown) into a RAM (random access memory) and executing the program. That is, the control unit 40 is realized by the CPU executing a program stored in the storage device and controlling peripheral circuits such as an input / output circuit (not shown).

  The control unit 40 includes a distance measuring device 100. The distance measuring device 100 measures the distance between the tip (edge) of the probe 6 and the surface of the workpiece 9, and includes an edge specifying unit 101, a straight line inserting unit 102, an overlap determining unit 103, and a distance calculating unit. 104.

  The edge identifying unit 101 captures a digitized image from the USB video capture 4. The image is an image obtained by capturing the secondary image (shadow or reflection image) appearing on the surface of the work 9 and the probe 6 by irradiating the probe 6 with light from the LED lamp 7.

  The edge specifying unit 101 specifies the tip of the probe 6 (the tip on the workpiece 9 side, hereinafter referred to as an edge) in the captured image. Since most of the probes 6 are cylinders or cones, the front center portion of the probe 6 is the most protruding portion with respect to the CCD camera 3. Therefore, the edge specifying unit 101 specifies the most protruding portion as the edge of the probe 6. Even in the case of the probe 6 in which the most protruding portion does not exist (for example, when the tip is flat), the edge specifying unit 101 specifies the front center portion of the probe as an edge.

  Thereafter, the edge specifying unit 101 transmits information indicating the edge position of the probe 6 together with the digitized image acquired from the USB video capture 4 to the straight line insertion unit 102.

  Note that the method of specifying the edge position of the probe 6 by the edge specifying unit 101 may be performed by a method used in conventional image processing, and thus detailed description thereof is omitted here.

  The straight line insertion unit 102 irradiates the probe 6 with the secondary image (shadow or reflection image) that appears on the surface of the work 9 by irradiating the probe 6 with light from the above-mentioned image, that is, the LED lamp 7. The captured image and information indicating the edge position of the probe 6 are received. The straight line insertion unit 102 receives the image and information indicating the edge position of the probe 6. Then, the straight line insertion unit 102 inserts a straight line along the outer edge of the secondary image on the image. Hereinafter, the straight line is referred to as a first straight line. The position where the straight line insertion unit 102 inserts the first straight line will be described in detail later with reference to FIG.

  Here, when a shadow appears on the surface of the work 9 by irradiating the probe 6 with light from the LED lamp 7, the outer edge of the shadow is indicated by a straight line according to the shape of the probe 6 (cylinder, cone, rod, etc.). The straight line insertion unit 102 inserts a first straight line along the outer edge of the shadow into the image. On the other hand, when a reflected image appears on the surface of the work 9 by irradiating the probe 6 with light from the LED lamp 7, the straight line insertion unit 102 displays the first straight line passing through the edge portion of the probe 6 in the reflected image on the image. Insert into.

  Furthermore, in addition to the first straight line, the straight line insertion unit 102 inserts the second and third straight lines that pass through the edge of the probe 6 specified by the edge specifying unit 101 into the image. Note that the second straight line is a straight line extending in the longitudinal direction of the probe 6 in the image and passing through the edge of the probe 6 specified by the edge specifying unit 101. The third straight line is a straight line that is perpendicular to the second straight line and passes through the edge of the probe 6 specified by the edge specifying unit 101 in the image. Here, the second and third straight lines do not move the CCD camera 3 and the probe because the CCD camera 3, the probe 6, and the LED lamp 7 are held so as to be movable integrally with the surface of the work 9. As long as it is fixed.

  As described above, the straight line insertion unit 102 inserts the first to third straight lines into the image. Then, the straight line insertion unit 102 transmits information indicating the first to third straight lines to the overlap determination unit 103. Further, the straight line insertion unit 102 transmits information indicating the edge position of the probe 6 acquired from the edge specification unit 101 to the overlap determination unit 103. However, the information indicating the edge position of the probe 6 may be realized by a configuration transmitted from the edge specifying unit 101 to the overlap determining unit 103.

  Note that the method of inserting the first to third straight lines into the image by the straight line insertion unit 102 may be performed by a method used in conventional image processing, and thus detailed description thereof is omitted here.

  The overlap determination unit 103 receives information indicating the first to third straight lines inserted by the straight line insertion unit 102 from the straight line insertion unit 102, and indicates the edge position of the probe 6 from the edge specifying unit 101 or the straight line insertion unit 102. Receive information. Then, the overlap determination unit 103 determines whether or not the edge of the probe 6 specified by the edge specifying unit 101 and the first straight line inserted by the straight line insertion unit 102 overlap.

  That is, as the probe 6 and the surface of the work 9 approach each other, the overlap determining unit 103 approaches the first straight line inserted along the outer edge of the shadow and the edge of the probe 6 on the image. When the surface of the workpiece 9 comes into contact with the surface of the work 9, the property that the edge of the probe 6 and the first straight line overlap is used. Thereby, in the said image, the overlap determination part 103 determines with the edge of the probe 6 and the 1st straight line having overlapped, and the contact with the surface of the probe 6 and the workpiece | work 9 is confirmed.

  Note that whether or not the edge of the probe 6 and the first straight line overlap each other may be performed by a method used in conventional image processing, and thus detailed description thereof is omitted here.

  Subsequently, the overlap determination unit 103 transmits information indicating that the edge of the probe 6 and the first line overlap on the image to the distance calculation unit 104. In addition, the overlap determination unit 103 receives the edge calculation unit 104 or the straight line insertion unit from the distance calculation unit 104 together with information indicating the first to third straight lines inserted by the straight line insertion unit 102 and acquired from the straight line insertion unit 102. Information indicating the edge position of the probe 6 acquired from 102 is transmitted.

  The distance calculation unit 104 receives information indicating the first to third straight lines inserted by the straight line insertion unit 102 from the overlap determination unit 103, information indicating the edge position of the probe 6, and the edge of the probe 6 and the first straight line. And information indicating that they overlap.

  Then, the distance calculation unit 104 is configured such that when the probe 6 moves and the edge of the probe 6 is separated from the surface of the workpiece 9, the linear insertion unit 102 is inserted from the edge of the probe 6 specified by the edge specifying unit 101. Based on the distance to one straight line, the distance between the edge and the surface of the workpiece 9 is calculated. Note that the distance calculation unit 104 may calculate the distance between the edge and the surface of the work 9 by receiving information indicating that the edge of the probe 6 and the first straight line have overlapped, or the trigger Regardless of the presence or absence, the distance between the edge and the surface of the workpiece 9 may be calculated.

  Hereinafter, three methods for the distance calculation unit 104 to calculate the distance are [Distance calculation method 1 by the distance calculation unit 104], [Distance calculation method 2 by the distance calculation unit 104], and [Distance calculation method by the distance calculation unit 104]. 3].

[Distance Calculation Method 1 by Distance Calculation Unit 104]
The distance measuring device 100 calculates the distance between the edge and the surface of the workpiece 9 as 0 when all the first to third straight lines intersect at the edge of the probe 6 specified by the edge specifying unit 101. In other words, the second and third straight lines are originally straight lines passing through the edge of the probe 6 specified by the edge specifying unit 101. Therefore, the distance measuring apparatus 100 calculates the distance between the edge and the surface of the work 9 as 0 when the first straight line passes through the edge (when the first straight line overlaps the edge). In the sample application device 50, the amount of movement of the probe 6 that is moved by one operation of the Z-axis actuator 12c is known.

  Therefore, when the sample coating apparatus 50 is initially operated, the probe 6 is moved by superimposing the first straight line on the edge of the probe 6 specified by the edge specifying unit 101, and the edge of the probe 6 is moved to the workpiece 9. When away from the surface, the distance calculation unit 104 can calculate the distance between the edge and the surface of the workpiece 9 based on the movement amount and movement direction of the Z-axis actuator 12c.

[Distance Calculation Method 2 by Distance Calculation Unit 104]
Next, another method in which the distance calculation unit 104 calculates the distance will be described.

  The distance calculation unit 104 acquires information indicating the inserted first to third straight lines from the straight line insertion unit 102, and calculates the distance between the second straight lines sandwiched between the first and third straight lines based on the information. At this time, the storage device (not shown) of the sample coating apparatus 50 stores a correlation table indicating the correlation between the actual distance between the edge and the surface of the workpiece 9 and the distance between the second straight lines sandwiched between the first and third straight lines. Prepare. Then, the distance calculation unit 104 can derive the actual distance between the edge corresponding to the calculated distance on the second straight line and the surface of the workpiece 9 with reference to the correlation table.

[Distance Calculation Method 3 by Distance Calculation Unit 104]
Next, still another method in which the distance calculation unit 104 calculates the distance will be described.

  Types of probe 6, distance between probe 6 and surface of workpiece 9, number of LED lamps 7, position of LED lamp 7, angle of CCD camera 3 with respect to probe 6, positional relationship between CCD camera 3 and LED lamp 7, etc. Images under various conditions are taken and stored in a storage device (not shown) of the sample coating apparatus 50. At the same time, the distance between the edge of the probe 6 and the surface of the workpiece 9 under each condition is also measured and stored in the storage device in association with the corresponding image.

  Then, the distance calculation unit 104 captures an image (secondary image (shadow or reflection image) appearing on the surface of the work 9 when the CCD camera 3 irradiates the probe 6 with light from the LED lamp 7 and the probe 6). ) Is imaged, it is read whether the same image is stored in the image stored in the storage device. Then, when the same image is stored in the storage device, the distance calculation unit 104 reads the distance between the edge of the probe 6 and the surface of the workpiece 9 stored in association with the image. Thereby, the distance calculation unit 104 can acquire (calculate) the distance between the edge of the probe 6 and the surface of the workpiece 9.

  The distance calculation unit 104 can calculate the distance between the edge and the surface of the workpiece 9 by the various methods described above.

  Subsequently, the distance calculation unit 104 transmits information indicating the distance between the edge and the surface of the workpiece 9 to the display device 60.

  Here, the display device 60 includes a display control unit 61 and a display unit 62.

  The display control unit 61 acquires information indicating the distance between the edge and the surface of the work 9 from the distance calculation unit 104 and displays the information on the display unit 62 in a state that can be confirmed by the user. And the converted information is output to the display unit 62. The display unit 62 includes a display device such as an LCD (liquid crystal display), a PDP (plasma display panel), or a CRT (cathode-ray tube) display.

  In this way, the distance calculation unit 104 transmits information indicating the distance between the edge and the surface of the work 9 to the display device 60, so that the user can determine the distance between the edge and the surface of the work 9. Can be confirmed.

  The distance calculation unit 104 can also be configured to transmit information indicating the distance between the edge and the surface of the workpiece 9 to the drive control unit 12d.

  As described above, the drive control unit 12d is for controlling the driving of the moving device 12. Accordingly, when the information indicating the distance between the edge and the surface of the workpiece 9 is input to the drive control unit 12d, the drive control unit 12d allows the user to determine the distance between the edge and the surface of the workpiece 9. The distance can be automatically controlled.

  The details of each part included in the distance measuring apparatus 100 have been described above. Next, an example of insertion of the first to third straight lines by the straight line insertion unit 102 will be described.

[Linear insertion example of the straight line insertion section 102]
The straight line insertion unit 102 applies first to third straight lines to an image obtained by capturing the secondary image (shadow or reflected image) appearing on the surface of the work 9 by irradiating the probe 6 with light from the LED lamp 7 and the probe 6. insert. 3 to 5 are images showing examples of straight line insertion by the straight line insertion unit 102. FIG.

  First, FIG. 3 will be described. FIG. 3 is an image showing a state in which the first straight line L1, the second straight line L2, and the third straight line L3 are inserted in a state where the distance between the edge of the probe 6 and the surface of the workpiece 9 is 0 μm.

  In the figure, one shadow 300 of the probe 6 appears on the surface of the work 9. This corresponds to the case where the sample coating device 50 includes one LED lamp 7. Since the shadow 300 of the probe 6 extends to the right side of the drawing, it can be seen that the LED lamp 7 irradiates the probe 6 with light from the left side of the drawing. The same applies to FIGS. 4 and 5.

  In FIG. 3, the straight line insertion unit 102 inserts a first straight line L1, a second straight line L2, and a third straight line L3 into the image. Here, a specific position where the first straight line L1 is inserted will be described. In addition, since the position where the 2nd straight line L2 and the 3rd straight line L3 are inserted is as above-mentioned, description here is abbreviate | omitted.

  As described above, the straight line insertion unit 102 forms a straight line along the outer edge of the shadow 300 in an image obtained by capturing the shadow 300 and the probe 6 that appear on the surface of the work 9 by irradiating the probe 6 with light from the LED lamp 7. Insert. In FIG. 3, two outer edges of the shadow 300 appear ((a) and (b) in the figure). And the straight line insertion part 102 has inserted the 1st straight line L1 in the outer edge (b) side. This is because when the first straight line L1 is inserted on the outer edge (a) side, the first straight line L1, the second straight line L2, and the third straight line L3 are all at the edge of the probe 6 specified by the edge specifying unit 101. This is because the distance between the edge and the surface of the workpiece 9 does not become zero when intersecting.

  On the other hand, when the first straight line L1 is inserted on the outer edge (b) side, the first straight line L1, the second straight line L2, and the third straight line at the edge of the probe 6 specified by the edge specifying unit 101. When all of L3 intersect, the distance between the edge and the surface of the work 9 becomes zero. That is, the first straight line L1 inserted by the straight line insertion unit 102 is the outer edge of the shadow 300, and the lower side of the image captured by the CCD camera 3 in which the shadow 300 is not hidden by the probe 6 (which can be said in FIG. 3). For example, it is the outer edge of the shadow 300 located on the lower side of the drawing.

  Subsequently, returning to the description of FIG. 3, the distance measuring apparatus 100 is configured such that all of the first straight line L1, the second straight line L2, and the third straight line L3 intersect at the edge of the probe 6 specified by the edge specifying unit 101. In addition, the distance between the edge and the surface of the workpiece 9 is calculated as zero. In this regard, in FIG. 3, since the first straight line L1, the second straight line L2, and the third straight line L3 all intersect at the edge, the distance measuring device 100 calculates the distance between the edge and the surface of the workpiece 9. Calculate as 0.

  Next, FIG. 4 is an image showing a state in which the first straight line L1, the second straight line L2, and the third straight line L3 are inserted in a state where the distance between the edge of the probe 6 and the surface of the work 9 is 50 μm. It is. FIG. 5 is an image showing a state in which the first straight line L1, the second straight line L2, and the third straight line L3 are inserted in a state where the distance between the edge of the probe 6 and the surface of the work 9 is 100 μm. is there.

  As shown in both figures, as the distance between the edge of the probe 6 and the surface of the workpiece 9 increases, the distance between the first straight line L1 and the second straight line L2 sandwiched between the third straight lines L3 increases. Since the method for calculating the distance between the edge and the surface of the workpiece 9 by the distance calculation unit 104 is as described above, detailed description thereof is omitted here.

  Subsequently, FIG. 6 is an image showing a state in which the first straight line L1, the second straight line L2, and the third straight line L3 are inserted in a state where the distance between the edge of the probe 6 and the surface of the work 9 is 100 μm. It is a figure showing an example when two shadows 300 appear using two LED lamps 7.

  In the figure, two shadows 300 of the probe 6 appear on the surface of the work 9. This is because the sample coating apparatus 50 includes two LED lamps 7. Since the shadow 300 of the probe 6 extends to the right and left sides of the drawing, it can be seen that the two LED lamps 7 irradiate the probe 6 with light from the left and right sides of the drawing, respectively.

  In the figure, the straight line insertion portion 102 inserts a first straight line L1 along the outer edge of the right shadow 300. However, the straight line insertion unit 102 can also insert the first straight line L1 along the outer edge of the left shadow 300, and in any case, the distance between the edge of the probe 6 and the surface of the workpiece 9 is calculated. can do. In any case, when all of the first straight line L1, the second straight line L2, and the third straight line L3 intersect at the edge of the probe 6 specified by the edge specifying unit 101, the edge and the workpiece This is because the distance from the surface of 9 is zero.

  As described above, the distance measuring apparatus 100 is configured so that the straight line insertion unit 102 inserts the first straight line L1 while paying attention to any one of the shadows 300 even when there are a plurality of shadows 300. The distance between the edge and the surface of the work 9 can be calculated.

[When a reflected image appears on the surface of the work 9]
In the above [Linear insertion example of the linear insertion portion 102], the case where the shadow of the probe 6 appears on the surface of the workpiece 9 has been described. However, the shadow of the probe 6 is generated on the surface of the work 9 depending on the state of the surface of the work 9 (material (silicon, glass, etc.), color, surface roughness, etc.) and the position / angle of the LED lamp 7 with respect to the probe 6. Otherwise, a reflected image of the probe 6 may be generated. In such a case, the distance between the edge of the probe 6 and the surface of the workpiece 9 can be calculated using the reflected image.

  FIG. 7 is an image showing a case where the distance between the edge of the probe 6 and the surface of the work 9 is 0 μm when the reflection image 6a of the probe 6 is generated on the surface of the work 9 made of silicon. ) Is a case where one LED lamp 7 is used, and FIG. 7B is an image showing a case where a plurality of LED lamps 7 are used.

  FIG. 8 is an image showing a case where the distance between the edge of the probe 6 and the surface of the work 9 is 50 μm when the reflection image 6a of the probe 6 is generated on the surface of the work 9 made of silicon. FIG. 7A is an image showing a case where one LED lamp 7 is used, and FIG. 7B is an image showing a case where a plurality of LED lamps 7 are used.

  As shown in both figures, the reflected image 6 a of the probe 6 may be generated on the surface of the work 9 depending on the material of the surface of the work 9. Further, when the reflected image 6a is generated, a plurality of the reflected images 6a with respect to the probe 6 can be seen by comparing FIGS. 7 (a) and 8 (a) with FIGS. 7 (b) and 8 (b). By irradiating light from the direction, that is, by irradiating light from the plurality of LED lamps 7 to the probe 6, the shape of the tip of the probe 6 can be clearly imaged. This facilitates calculation of the distance between the probe 6 and the surface of the work 9.

  Here, when the reflected image 6 a is generated on the surface of the work 9, the distance calculation unit 104 calculates the distance between the probe 6 and the surface of the work 9 as follows. In addition, about the same content as the description performed with reference to FIG. For the sake of easy viewing, the first straight line L1, the second straight line L2, and the third straight line L3 are not shown in the drawing.

  First, the edge specifying unit 101 captures a digitized image from the USB video capture 4. The image is an image obtained by capturing the reflected image 6 a and the probe 6 that appear on the surface of the work 9 by irradiating the probe 6 with light from the LED lamp 7.

  The edge specifying unit 101 specifies the edge position of the probe 6 in the captured image. Since most of the probes 6 are cylinders or cones, the front center portion of the probe 6 is the most protruding portion with respect to the CCD camera 3. Therefore, the edge specifying unit 101 specifies the most protruding portion as the edge of the probe 6.

  The straight line insertion unit 102 receives the image and information indicating the edge position of the probe 6 from the edge specifying unit 101. Then, the straight line insertion unit 102 converts the reflected image 6a into the image, that is, the image obtained by capturing the reflected image 6a and the probe 6 that appear on the surface of the workpiece 9 by irradiating the probe 6 with light from the LED lamp 7. A first straight line is inserted along the outer edge (in the case of a reflected image, the shadow edge of the probe 6). The first straight line is parallel to the third straight line inserted by the straight line insertion unit 102.

  After that, the distance calculation unit 104 receives information indicating the first to third straight lines inserted by the straight line insertion unit 102 from the straight line insertion unit 102 or the overlap determination unit 103, and the edge specifying unit 101, the straight line insertion unit 102, or Information indicating the edge position of the probe 6 is received from the overlap determination unit 103. The distance calculation unit 104 calculates the distance between the edge and the surface of the workpiece 9 based on the distance from the edge of the probe 6 specified by the edge specifying unit 101 to the first straight line inserted by the straight line insertion unit 102. As the distance calculation method, any one of [Distance calculation method 1 by distance calculation unit 104] and [Distance calculation method 2 by distance calculation unit 104] described above may be used.

  In addition, the distance calculation unit 104 may calculate the distance between the edge and the surface of the work 9 by receiving the information indicating that the edge of the probe 6 and the first straight line overlap each other as a trigger. Regardless of the presence or absence, the distance between the edge and the surface of the workpiece 9 may be calculated.

  In this way, even when the reflected image 6 a is generated on the surface of the work 9, the distance measuring device 100 can calculate the distance between the probe 6 and the surface of the work 9.

  In addition, FIG. 9, FIG. 10 is shown as another example which produces | generates the reflected image 6a on the surface of the workpiece | work 9. In FIG.

  FIG. 9 is an image showing a case where the distance between the edge of the probe 6 and the surface of the ITO plate is 0 μm when the reflection image 6a of the probe 6 is generated on the surface of the ITO plate. FIG. 9B is an image showing a case where a plurality of LED lamps 7 are used when one LED lamp 7 is used.

  FIG. 10 is an image showing a case where the distance between the edge of the probe 6 and the surface of the ITO plate is 50 μm when the reflection image 6a of the probe 6 is generated on the surface of the ITO plate. FIG. 10B is an image showing a case where a plurality of LED lamps 7 are used when one LED lamp 7 is used.

  As shown in FIGS. 9, 10, 7, and 8, the reflected image 6 a may be generated on the surface of the work 9. In this respect, the distance measuring apparatus 100 calculates the distance between the edge of the probe 6 and the surface of the work 9 regardless of whether the secondary image is a shadow of the probe 6 or a reflected image 6a of the probe 6. Can do. Therefore, the highly convenient distance measuring device 100 can be provided to the user.

[An angle of the CCD camera 3 with respect to the probe 6]
In order for the CCD camera 3 to capture a clear secondary image (shadow or reflected image), it is necessary to consider the angle of the CCD camera 3 with respect to the probe 6. This will be described with reference to FIGS.

  11 to 14 show shadows 300 appearing on the surface of the work 9 imaged by the CCD camera 3 when the angle of the imaging direction of the CCD camera 3 with respect to the probe 6 is set to 75 °, 70 °, 60 °, and 45 °. And (c) are images when the distances between the edge of the probe 6 and the surface of the work 9 are 0 μm, 50 μm, and 100 μm, respectively.

  As can be seen from the above figures, the surface of the work 9 can be observed in more detail as the angle of the imaging direction of the CCD camera 3 with respect to the probe 6 is reduced. However, when the angle becomes small, it becomes difficult to observe the positional relationship between the probe 6 and the shadow 300, particularly the distance between the edge of the probe 6 and the surface of the workpiece 9. That is, as the angle of the imaging direction of the CCD camera 3 with respect to the probe 6 decreases, the ability (spatial resolution) to determine the distance between the edge of the probe 6 and the surface of the work 9 decreases. This is also shown in FIG. 14B, for example, and the shadow 300 is very close to the probe 6 even though the distance between the tip of the probe 6 and the surface of the workpiece 9 is 50 μm. You can only get the image you are doing.

  Based on such a result, it is preferable that the CCD camera 3 is held by the holding unit 13 within an imaging direction of 40 ° to 80 °, preferably 50 ° to 65 ° with respect to the probe 6. The present inventors have found that. By setting such an angle, the positional relationship between the probe 6 and the shadow 300, particularly the distance between the edge of the probe 6 and the surface of the workpiece 9 can be easily observed.

  The diameter of the white circle on the surface of the work 9 shown in each figure is 800 μm. In addition, Work 9 uses Bruker's Prespotted AnchorChip 384 MALDI matrix spots. Furthermore, the probe in each figure is a cemented carbide pin manufactured by electric discharge machining of Mitsubishi Materials MF20, and its tip diameter is 100 μm.

  Next, the state of the sample coating apparatus 50 when the angle of the imaging direction of the CCD camera 3 with respect to the probe 6 is set to 75 °, 60 °, and 45 ° will be described with reference to FIGS.

  15 to 17 are images showing the state of the sample coating apparatus 50 when the angles of the imaging direction of the CCD camera 3 with respect to the probe 6 are set to 75 °, 60 °, and 45 °, respectively.

  As can be seen from FIG. 15, even when the angle of the imaging direction of the CCD camera 3 with respect to the probe 6 is set to 75 °, the CCD camera 3 does not come into contact with the surface of the work 9 even though it is quite close. In addition, since the lower end of the CCD camera 3 is positioned above the tip of the probe 6, the CCD camera 3 and the work 9 do not collide.

[Position relationship between CCD camera 3 and LED lamp 7]
In order for the CCD camera 3 to capture a clear secondary image (shadow or reflected image), it is necessary to consider the positional relationship between the CCD camera 3 and the LED lamp 7. This will be described with reference to FIGS.

  18 to 20 show the shadow 300 and the probe 6 appearing on the surface of the work 9 imaged by the CCD camera 3 when the angle of the imaging direction of the CCD camera 3 with respect to the probe 6 is set to 75 °, 60 °, and 45 °. (A) to (e) respectively show the irradiation direction of the LED lamp 7 that irradiates toward the center of the probe 6 in a plan view with respect to the imaging direction of the CCD camera 3. Direction rotated about 110-130 ° to the left around the probe 6, direction rotated about 25 ° to the left, direction rotated 25-30 ° to the right, direction rotated 75-80 ° to the right, left It is a figure which shows an image when setting to the direction rotated about 60 degrees. In each figure, the distance between the tip of the probe 6 and the surface of the workpiece 9 is 50 μm.

  Among these, FIGS. 18B and 19C, FIGS. 19B and 20C, and FIGS. 20B and 20C are irradiation directions of the LED lamp 7 that irradiates toward the center of the probe 6. Appearing on the surface of the work 9 when it is disposed in a region rotated about 25 ° to the left and 25 ° to 30 ° to the right in a plan view with respect to the imaging direction of the CCD camera 3 It is a figure which shows the image which imaged 300 and the probe 6. FIG. As shown in each figure, when the LED lamp 7 is arranged within a small angle range with respect to the CCD camera 3, the shadow 300 appearing on the surface of the workpiece 9 is hidden by the probe 6, and the edge of the probe 6 It is difficult to calculate the distance to the surface of the workpiece 9 using the shadow 300. Based on such a result, the LED lamp 7 is in a range close to the CCD camera 3 side from an axis perpendicular to the imaging direction of the CCD camera 3 through the center of the probe 6 in plan view. The inventors of the present application have found that it is necessary to arrange so as not to be included in a certain region.

  Further, as a result of considering FIG. 18 and the like, the LED lamp 7 is seen from the axis orthogonal to the imaging direction of the CCD camera 3 through the center of the probe 6 and to the CCD camera 3 side and the opposite side in plan view. Of the probe 6 generated on the surface of the work 9 when it is disposed within a range of 45 ° with respect to the CCD camera 3 and preferably within a range of 30 ° with respect to the opposite side. The inventors of the present application have found that the shadow 300 can be clearly imaged.

  When a plurality of LED lamps 7 are used, it is preferable that the number of LED lamps 7 be limited to about four in order for the CCD camera 3 to capture a clear shadow. On the other hand, the present inventors have found that when a reflection image is captured, a clear front reflection image can be obtained by using a plurality of LED lamps 7 as compared with the case of using one LED lamp 7.

  Here, in the above description, the LED lamp 7 is in a range close to the CCD camera 3 side from an axis orthogonal to the imaging direction of the CCD camera 3 through the center of the probe 6 in plan view. I mentioned that it is necessary to arrange so that it is not included in a certain area. However, this can be said when the distance between the edge of the probe 6 and the surface of the workpiece 9 is calculated using a shadow, and when the distance is calculated using a reflected image. Not true. Rather, in the case of using a reflection image, when the LED lamp 7 applies strong light to the probe 6 and pays attention to halation in which the area around the light is blurred white, the front reflection is obtained. May be valid.

  Although not shown, when the distance between the edge of the probe 6 and the surface of the workpiece 9 is calculated using a reflected image, the LED lamp 7 is in the imaging direction of the CCD camera 3 in plan view. The inventors of the present application preferably hold the holder 13 within a range of 30 ° to 60 ° with respect to the CCD camera 3 from an axis orthogonal to the center of the probe 6 with respect to the CCD camera 3 side. Confirmed.

[Effects obtained by the distance measuring apparatus 100]
Hereinafter, effects obtained by the distance measuring apparatus 100 will be described.

  According to the above configuration, the edge specifying unit 101 specifies the edge of the probe 6 in the secondary image of the probe 6 that appears on the surface of the work 9 captured by the CCD camera 3 and the image of the probe 6. The straight line insertion unit 102 inserts a first straight line along the outer edge of the secondary image in the image. Then, the overlap determining unit 103 determines the overlap between the edge specified by the edge specifying unit 101 and the first straight line inserted by the straight line inserting unit 102.

  That is, as the probe 6 and the surface of the workpiece 9 approach each other, the distance measuring device 100 approaches the edge and the first straight line inserted along the outer edge of the secondary image on the image, and the probe 6 and the workpiece 9 are closer to each other. This utilizes the property that the edge and the first straight line overlap each other on the image when the surface touches. Therefore, the contact between the probe 6 and the surface of the workpiece 9 can be confirmed by determining that the edge determination unit 103 has overlapped the edge and the first straight line.

  Therefore, the distance measuring apparatus 100 regards that the probe 6 and the surface of the work 9 are in contact with each other when the edge and the first straight line overlap each other, and uses the point as a reference in the moving amount and moving direction of the probe 6. Based on this, the distance between the edge and the surface of the workpiece 9 can be measured.

  Further, as described above, the distance measuring apparatus 100 generates the secondary image of the probe 6 on the surface of the workpiece 9 and inserts the edge specified by the edge specifying unit 101 and the outer edge of the secondary image. The distance between the edge and the surface of the workpiece 9 is measured from the positional relationship with one straight line.

  Therefore, unlike the image analysis method using the LAB technique, the distance measuring apparatus 100 can measure the distance between the edge and the surface of the work 9 without being influenced by the size of the probe 6.

  Further, the distance measuring device 100 has a configuration in which one or more LED lamps 7, the CCD camera 3, and the probe 6 are held so as to be integrally movable with respect to the surface of the workpiece 9.

  Thereby, since the positional relationship among the one or more LED lamps 7, the CCD camera 3, and the probe 6 is maintained in a fixed state, the position of the probe 6 moves for each measurement in the image to be captured. A situation in which the measurement results vary can be avoided, and a more stable measurement result can be provided to the user. Moreover, because of the measurement method, the distance between the edge and the surface of the work 9 can be measured even when the shape of the surface of the work 9 is not stable (for example, when the surface of the work 9 is inclined). .

  In addition, since the one or more LED lamps 7, the CCD camera 3, and the probe 6 are held so as to be integrally movable with respect to the surface of the work 9, the distance measuring device 100 has a work area for the surface of the work 9. Therefore, it is possible to cope with the surface of the huge workpiece 9. That is, in the conventional sample coating apparatus, since the surface side of the workpiece 9 is controlled to be movable, a plurality of probes 6 are used on the surface of the same workpiece 9 depending on the shape of the surface of the workpiece 9. It was difficult to apply this sample.

  On the other hand, when the distance measuring device 100 is applied to a sample coating device, a plurality of different samples can be applied to the surface of the same workpiece 9 in a short time. Therefore, by using the distance measuring device 100, a significant productivity improvement can be brought to the user.

  Further, the distance measuring apparatus 100 includes a calculation unit that calculates the distance between the edge and the surface of the workpiece 9 based on the distance from the edge specified by the edge specifying unit 101 to the first straight line inserted by the straight line insertion unit 102. It is a configuration.

  As described above, in the distance measuring apparatus 100, the edge specifying unit 101 specifies the edge of the probe 6 in the secondary image of the probe 6 that appears on the surface of the work 9 captured by the CCD camera 3 and the image of the probe 6. . Further, the straight line insertion unit 102 inserts a first straight line along the outer edge of the secondary image in the image. Further, in the distance measuring apparatus 100, the distance calculation unit 104 determines whether the edge and the surface of the workpiece 9 are based on the distance from the edge specified by the edge specifying unit 101 to the first straight line inserted by the straight line inserting unit 102. Calculate the distance.

  Specifically, for example, the distance is calculated by preparing in advance a correlation between the actual distance between the edge and the surface of the workpiece 9 and the distance from the edge to the first straight line inserted by the straight line insertion unit 102. The unit 104 can calculate the distance between the edge and the surface of the workpiece 9 based on the distance from the edge to the first straight line. Thereby, the structure by which the distance of an edge and the surface of the workpiece | work 9 is calculated automatically is realizable.

  Here, the distance from the edge to the first straight line is the intersection of the first straight line that passes through the edge and extends in the longitudinal direction of the probe 6 in the image and the first straight line inserted by the straight line insertion portion 102 and the edge. The distance between.

  Further, in the distance measuring apparatus 100, the secondary image is a shadow of the probe 6 or a reflected image of the probe 6.

  According to the above configuration, the distance measuring apparatus 100 can handle the secondary image that is either the shadow of the probe 6 or the reflected image of the probe 6. That is, the distance measuring apparatus 100 can measure the distance between the edge and the surface of the work 9 even when a reflected image of the probe 6 is generated instead of the shadow of the probe 6 due to the material of the surface of the work 9 or the like. .

  Furthermore, in the distance measuring device 100, a plurality of LED lamps 7 exist.

  According to the above configuration, the distance measuring device 100 includes a plurality of LED lamps 7 that irradiate the probe 6 with light. Thereby, since light is irradiated with respect to the probe 6 from a plurality of directions, the CCD camera 3 can capture the shape of the edge of the probe 6 clearly. As a result, the distance measuring apparatus 100 can more accurately measure the distance between the edge of the probe 6 and the surface of the workpiece 9.

  It can be seen that the above configuration is also effective from the characteristic that a reflected image is generated more clearly on the surface of the work 9 by irradiating the probe 6 with light from a plurality of directions.

  Further, in the distance measuring apparatus 100, the LED lamp 7 is 45 from the axis orthogonal to the imaging direction of the CCD camera 3 through the center of the probe 6 in a plan view with respect to the CCD camera 3 side and the opposite side. This is a configuration arranged in a region within a range of °.

  Further, in the distance measuring apparatus 100, the LED lamp 7 is viewed from 30 ° from the axis orthogonal to the imaging direction of the CCD camera 3 through the center of the probe 6 in the plan view and from the CCD camera 3 side. It is the structure arrange | positioned in the area | region which exists in the range of 60 degrees.

  With the above configuration, the CCD camera 3 can more clearly capture the secondary image of the probe 6 generated on the surface of the work 9, and more accurately measures the distance between the edge of the probe 6 and the surface of the work 9. be able to.

  Further, in the distance measuring apparatus 100, the CCD camera 3 is configured by combining a CCD camera having an outer diameter of 7 mm and a telephoto lens having a focal length of 15 mm.

  Conventionally, since the lens portion of the CCD camera 3 used for taking an image has a C-mount, bringing the CCD camera 3 close to the surface of the work 9 means installation in the vertical direction (gravity direction). It was good to say that it was impossible.

  In this respect, with the above-described configuration, it is possible to observe the distance between the probe 6 and the lens several tens of millimeters even at a zoom ratio of about 100 times, and work on the surface of the workpiece 9. The area limitation can be reduced. In addition, since the CCD camera 3 having the above-described configuration has been reduced in weight, it can be mounted on the same drive shaft as the probe 6. Thereby, the distance measuring device 100 can easily realize a configuration in which one or more LED lamps 7, the CCD camera 3, and the probe 6 are held so as to be movable integrally with the surface of the workpiece 9. it can.

  Further, in the distance measuring apparatus 100, the CCD camera 3 is configured such that its imaging direction is held within a range of 40 ° to 80 °, preferably 50 ° to 65 ° with respect to the probe 6.

  With the above configuration, the secondary image of the probe 6 generated on the surface of the workpiece 9 can be captured more clearly, and the distance between the edge of the probe 6 and the surface of the workpiece 9 can be measured more accurately.

  As described above, various effects can be expected from the distance measuring apparatus 100.

[Other Examples (Cutting Device 200)]
In the above description, the sample coating device 50 including the distance measuring device 100 has been described. However, since the distance measuring device 100 is a highly versatile device, it can be easily incorporated into other various devices. Examples of the application include a sampling device, a micro processing device, and a cutting device. In these apparatuses, since it is necessary to accurately measure and control the distance between the probe (or drill or the like) and the workpiece surface, the distance measuring apparatus 100 according to the present invention can be suitably applied.

  Here, the cutting device 200 provided with the distance measuring device 100 will be described with reference to FIG. FIG. 21 is a diagram illustrating a schematic configuration of a cutting device 200 in which the distance measuring device 100 is incorporated. In addition, the description about the same content as the description performed with reference to FIG. 2 etc. is abbreviate | omitted. In FIG. 21, the description of the USB video capture 4, the personal computer 5, the mobile device 12 and the like described in FIG. 2 is omitted. However, the cutting device 200 can be realized by incorporating the components described in FIG. 21 into the moving device 12 in FIG. 2.

  The cutting device 200 is a device that performs micro processing on the surface of the workpiece 9 in micro units, and in particular, is a device that performs cutting on the surface of the workpiece 9. The cutting apparatus 200 includes a lens 1, an extension tube 2, a CCD camera 3, a USB video capture 4, a personal computer 5, a drill 201, an LED lamp 7, an LED illumination power supply 8, a work 9, a work The configuration includes a stage 10, a moving device 12, a holding unit 13, a spindle 202, and a brushless motor 203.

  Here, the drill 201 performs drilling (cutting) with a drill on an object after the distance between itself and the surface of the work 9 is accurately controlled. The micro drill NSMD is used. The micro drill NSMD is present from those having a minimum outer diameter of 0.01 mm suitable for ultra-fine processing, and any of them may be used. The drill used may be a product of another company.

  The spindle 202 uses NR-2550 manufactured by Nakanishi Co., Ltd., and the brushless motor 203 uses EM25-5000-J4 manufactured by Nakanishi Co., Ltd. Is given.

  By providing the above configuration, the cutting device 200 including the distance measuring device 100 can achieve the following effects. That is, the distance measuring device 100 can measure the distance between the drill 201 and the surface of the workpiece 9 and can be applied without being influenced by the diameter of the drill 201. Therefore, since the cutting device 200 provided with the distance measuring device 100 uses a drill with a thin outer diameter of a minimum diameter of 0.01 mm to a maximum diameter of 0.10 mm, it is possible to realize micro processing in micro units. Can do. And in the field of micromachining, since there is a problem of high dependence on few craftsmen in Japan, it is the same even for an amateur by using the cutting device 200 provided with the distance measuring device 100. It is possible to perform a fine processing of a degree. At the same time, a huge economic effect on the manufacturing industry can be expected.

[Countermeasures for problems of conventional technology]
As described above, depending on the type of workpiece surface, a specular phenomenon occurs at the tip of the probe (see FIG. 23). In this case, a virtual image of the probe 6 is displayed on the surface of the work 9, and the distance measuring device 100 has difficulty in calculating the distance between the probe 6 (or a drill or the like) and the surface of the work 9.

  Therefore, as a countermeasure to the above problem, there is a countermeasure of coating the probe 6 with a fluorine-based material. This is because it is possible to prevent the specular phenomenon at the tip by coating the probe 6 with a fluorine-based material (FIG. 22). As a result, the distance measuring device 100 can calculate the distance between the probe 6 (or drill or the like) and the surface of the work 9 and can solve the above problem.

  Furthermore, the following problems were pointed out as problems of the prior art. In other words, as pointed out with respect to the invention described in Patent Document 1, it is necessary to make the width of the shadow of the probe generated on the surface array as narrow as possible. In order to make this possible, the angle of the camera with respect to the probe is set. It needs to be as large as possible. On the other hand, when the camera angle is increased in this way, it becomes difficult to observe changes on the surface. In particular, when the sample is applied in the state of a small point, the area of the point to be observed becomes extremely small, and even when the image magnification is small, even the presence of the point may not be grasped.

  In this respect, the distance measuring device 100 determines the angle of the CCD camera 3 relative to the probe 6 or the positional relationship between the CCD camera 3 and the LED lamp 7 in accordance with the purpose of the device in which the distance measuring device 100 is incorporated, the outer diameter of the probe 6 and the like. Adjustments are made as appropriate. As a result, the above-mentioned problems of the prior art can be overcome.

[Supplement]
Finally, each block of the distance measuring device 100, in particular, the edge specifying unit 101, the straight line inserting unit 102, the overlap determining unit 103, and the distance calculating unit 104 of the distance measuring device 100 may be configured by hardware logic. As described above, it may be realized by software using a CPU.

  That is, the distance measuring apparatus 100 includes a central processing unit (CPU) that executes instructions of a control program that realizes each function, a read only memory (ROM) that stores the program, and a random access memory (RAM) that expands the program. And a storage device (recording medium) such as a memory for storing the program and various data. An object of the present invention is a recording medium in which a program code (execution format program, intermediate code program, source program) of a control program of the distance measuring apparatus 100, which is software that realizes the above-described functions, is recorded so as to be readable by a computer. This can also be achieved by supplying the distance measuring device 100 and reading and executing the program code recorded on the recording medium by the computer (or CPU or MPU).

  Examples of the recording medium include a tape system such as a magnetic tape and a cassette tape, a magnetic disk such as a floppy (registered trademark) disk / hard disk, and a compact disk-ROM / MO / MD / digital video disk / compact disk-R. A disk system including an optical disk, a card system such as an IC card (including a memory card) / optical card, or a semiconductor memory system such as a mask ROM / EPROM / EEPROM / flash ROM can be used.

  Further, the distance measuring device 100 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication. A net or the like is available. Also, the transmission medium constituting the communication network is not particularly limited. For example, even in the case of wired such as IEEE 1394, USB, power line carrier, cable TV line, telephone line, ADSL line, etc., infrared rays such as IrDA and remote control, Bluetooth ( (Registered trademark), 802.11 wireless, HDR, mobile phone network, satellite line, terrestrial digital network, and the like can also be used. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The present invention generates a secondary image of the probe on the workpiece surface, and can measure the distance between the tip of the probe and the workpiece surface from the positional relationship between the secondary image and the tip of the probe. The present invention is applied to a measuring apparatus, and in particular, can be suitably applied to a sample coating apparatus, a sample collection apparatus, a micro processing apparatus, a cutting apparatus, and the like.

1 Lens (imaging device)
2 Extension tube 3 CCD camera 3a Camera body (imaging device)
3b Camera amplifier (imaging device)
4 USB video capture 5 PC 6 Probe 6a Probe reflected image 7 LED lamp (light source)
8 LED illumination power source 9 Work 10 Work stage 11 Trace application device 12 Moving device 12a X-axis actuator 12b Y-axis actuator 12c Z-axis actuator 12d Drive control unit 13 Holding unit 40 Control unit 50 Sample application device 60 Display device 61 Display control Unit 62 Display unit 100 Distance measuring device 101 Edge specifying unit (specifying means)
102 Straight insertion part (insertion means)
103 Overlap determination unit (determination means)
104 Distance calculation unit (calculation means)
200 Cutting device 201 Drill 202 Spindle 203 Brushless motor 300 Shadow L1 First straight line L2 Second straight line L3 Third straight line

Claims (10)

A secondary image that appears on the workpiece surface by irradiating the probe with light from the light source and the probe are picked up by the imaging device, and the distance between the tip of the probe and the workpiece surface using the image captured by the imaging device In a distance measuring device for measuring
Specifying means for specifying the tip in the image;
Insertion means for inserting a straight line along the outer edge of the secondary image in the image onto the image;
Determining means for determining an overlap between the tip portion specified by the specifying means and the straight line inserted by the insertion means;
The distance measuring device, wherein the one or more light sources, the imaging device, and the probe are held so as to be integrally movable with respect to the workpiece surface.   2. A calculation means for calculating a distance between the tip portion and the workpiece surface based on a distance from the tip portion specified by the specifying means to the straight line inserted by the insertion means. The distance measuring device described in 1.   The distance measuring device according to claim 1, wherein the secondary image is a shadow of the probe or a reflected image of the probe.   The distance measuring device according to claim 1, wherein a plurality of the light sources exist.   The light source is in a region in a range of 45 ° with respect to the imaging device side and the opposite side from an axis perpendicular to the imaging direction of the imaging device through the center of the probe in plan view. It is arrange | positioned, The distance measuring apparatus of any one of Claim 1 to 4 characterized by the above-mentioned.   The light source is in a region within a range of 30 ° to 60 ° with respect to the imaging device side from an axis orthogonal to the imaging direction of the imaging device through the center of the probe in plan view. It is arrange | positioned, The distance measuring apparatus of any one of Claim 1 to 4 characterized by the above-mentioned.   7. The imaging apparatus according to claim 1, wherein the imaging apparatus is arranged in a region in which an imaging direction is within a range of 40 ° to 80 °, preferably 50 ° to 65 ° with respect to the probe. The distance measuring device according to claim 1. A secondary image that appears on the workpiece surface by irradiating the probe with light from the light source and the probe are picked up by the imaging device, and the distance between the tip of the probe and the workpiece surface using the image captured by the imaging device A distance measuring method for measuring
A specifying step of specifying the tip in the image;
An insertion step of inserting a straight line along the outer edge of the secondary image in the image onto the image;
A determination step of determining an overlap between the tip portion specified in the specifying step and the straight line inserted in the insertion step. A secondary image that appears on the workpiece surface by irradiating the probe with light from the light source and the probe are picked up by the imaging device, and the distance between the tip of the probe and the workpiece surface using the image captured by the imaging device A distance measurement program for measuring
A specifying step of specifying the tip in the image;
An insertion step of inserting a straight line along the outer edge of the secondary image in the image onto the image;
A distance measurement program for causing a computer to execute a determination step of determining an overlap between the tip portion specified in the specifying step and the straight line inserted in the insertion step.   The computer-readable recording medium which recorded the distance measurement program of Claim 9.