JP2020169952A - Measuring device and measuring method - Google Patents

Abstract

To provide a measuring device and a measuring method that can enhance the horizontal resolution of an optical system and shorten a measurement time.SOLUTION: A measuring device uses a two-light focusing interferometer including imaging means that divides a light from a light source into two directions, irradiates a measured part with one division light and irradiates a reference plate with the other division light, combines reflected light reflected by the measured part and the reference plate, and captures an image of interference light. The imaging means relatively moves an image sensor having an image in which a photoelectric conversion part is opened in an area smaller than one pixel area with respect to the measured part, and shifts the image by the amount of the decimal part excluding the integer part of a movement amount expressed in pixel units, which is less than one pixel.SELECTED DRAWING: Figure 1

Description

The present invention relates to a measuring device and a measuring method, and more particularly to a measuring device and a measuring method using a two-luminous flux interferometry.

As a measuring device using the two luminous flux interferometry, for example, there is one described in Patent Document 1. As shown in FIG. 9, this measuring device (shape measuring device) includes a light source 1, a collimator lens 2, a beam splitter 3, a reference plate 4, an imaging lens 5, a CCD camera 6, and the like.

That is, the light (white light) emitted from the light source 1 is collimated by the collimator lens 2 and split in two directions by the beam splitter 3. One of the divided lights is applied to the measurement surface of the work 7 to be measured, and the other divided light is applied to the reference surface of the reference plate 4. The white light reflected from the irradiation on the measurement surface and the reference surface is combined by the beam splitter 3, and the interference light at that time is imaged by the CCD camera 6 via the imaging lens 5.

Japanese Unexamined Patent Publication No. 2011-89897

When using a conventional three-dimensional meter with white interference, it is necessary to increase the field of view (decrease the magnification). However, if the field of view is increased, the horizontal resolution will decrease. In order to maintain the horizontal resolution, it is necessary to move the field of view. Therefore, in such a three-dimensional meter with white interference, when measuring a field of view larger than that of the CCD camera (image sensor) 6 while maintaining the required horizontal resolution, the work 7 or the optical system is moved to obtain a plurality of fields of view. I had to shoot and paste them together.

When multiple fields of view are photographed and pasted together, it is necessary to move the fields of view in order to connect the fields of view, which increases the moving time. Further, in order to move the visual field, it is necessary to move a heavy object (workpiece or optical system), and the entire device (equipment) becomes large and complicated.

In view of the above problems, the present invention provides a measuring device and a measuring method capable of improving the horizontal resolution of the optical system and shortening the measuring time.

The measuring device of the present invention divides the light from the light source in two directions and irradiates the measured portion with one divided light and irradiates the reference plate with the other divided light from the measured portion and the reference plate. A measuring device using a two-light convergence interferometer having an imaging means for synthesizing reflected reflected light and imaging the interfering light. The imaging means has a photoelectric conversion portion having an area smaller than one pixel area. An image sensor having an open pixel is provided, and the image sensor and the part to be measured are relatively moved by the position moving means to obtain an integer portion of the amount of movement expressed in pixel units, which is less than one pixel. The pixel is shifted by the amount of the excluded fractional part.

According to the measuring device of the present invention, since an image sensor having pixels in which the photoelectric conversion portion is opened in an area smaller than one pixel area is used, the apparent pixel size of the image sensor is reduced and the horizontal resolution is improved. Can be made to. Moreover, the portion (missing portion) that cannot be measured due to the reduced pixel size can be complemented by the relative movement between the image sensor and the portion to be measured.

The opening of the photoelectric conversion portion of the image sensor can be configured by providing a light-shielding portion in the pixel. Here, the light-shielding portion can be composed of, for example, a paint (resin) containing a black pigment (carbon black), a metal vapor deposition film, a metal plate (etching or machining), or the like. As described above, the light-shielding portion can be provided with various simple configurations.

The opening of the photoelectric conversion portion of the image sensor can be formed by the light receiving surface of the photodiode. An image sensor having such a photodiode may be manufactured, and it is not necessary to provide a light-shielding portion, which is excellent in productivity.

The aperture area of the photoelectric conversion portion of the image sensor can be 7% or more and 30% or less of the one pixel area. Setting in this way is stable in production.

The aperture shape of the photoelectric conversion portion may be any of substantially circular, substantially elliptical, substantially square, and substantially rectangular. Here, the substantially circular shape is a concept that includes not only a perfect circle but also a shape that is close to a circle to some extent (such as a slightly elliptical shape or a shape having irregularities on the circumference). The abbreviated ellipse includes an actual ellipse and a shape close to an ellipse, and a shape close to an ellipse includes a compound circle and a shape formed by a circle and a straight line. .. The substantially square is an actual square and a shape substantially close to a square, and includes a substantially rectangle having rounded vertices and the like. The substantially rectangular shape is an actual rectangle and a shape substantially close to a rectangle, and includes a substantial rectangle having rounded vertices and the like.

The position moving means can be configured by a piezoelectric actuator that moves the image sensor with respect to the part to be measured. Here, the piezoelectric actuator is an actuator to which the piezo piezoelectric effect is applied, and therefore, it has high accuracy, high-speed response, high stop holding force, low power consumption, and no electromagnetic noise. It is compact and can be arranged at high density, and has advantages such as a simple structure.

The part to be measured may be at least one of the bonded wire, the joint portion thereof, and the joint portion to be bonded.

The light emitted from the light source is preferably monochromatic light or a plurality of colors. The monochromatic light source can be configured by a laser light source or an LED light source. Further, the multicolor light is light in which a plurality of types of monochromatic colors are mixed. The light emitted from the light source may be white light. Here, white light is light mixed with light having a wavelength of 380 nm to 750 nm. Therefore, if the two-luminous flux interferometry is used, the light of each color strengthens each other when the optical path length difference between the two optical paths is "integer multiple" of the wavelength, and weakens each other when "integer multiple + half wavelength". Then, the synthesis of the interference results of the light of all colors becomes the interference result of the white light, and when the optical path length difference is 0, the light of all wavelengths strengthens each other, and the interference of the white light becomes the brightest.

In the measurement method of the present invention, light is divided in two directions, one divided light is irradiated to the measured portion, and the other divided light is irradiated to the reference plate, which is reflected from the measured portion and the reference plate. This is a measurement method using a two-light convergence interference method that synthesizes reflected light and captures the interference light, and is an image sensor having an image in which the photoelectric conversion part is opened in an area smaller than one pixel area, and a cover. A device that moves the measurement site relative to the measurement site, shifts the image by the amount of the fractional part excluding the integer part of the movement amount expressed in pixel units, which is less than one pixel, and images the measurement target part with an image sensor. Is.

According to the measurement method of the present invention, since an image sensor having an image in which the electroconversion portion is opened in an area smaller than one pixel area is used, the apparent pixel size of the image sensor is reduced and the horizontal resolution is improved. Can be made to. Moreover, by reducing the pixel size, the portion that cannot be measured (missing portion) can be complemented by the relative movement between the image sensor and the portion to be measured.

The relative movement between the image sensor and the part to be measured may be a constant pitch or may be moved at an arbitrary indefinite pitch. Only the relative position movement between the image sensor in the X direction and / or the Y direction and the measured portion may be performed.

It is possible to move the relative position of the image sensor and the part to be measured in the X and / or Y directions, and scan the image sensor in the Z direction orthogonal to the X and Y directions, and the image sensor is being scanned in the Z direction. Can be set to relatively move the image sensor in the X and / or Y directions. In this case, for example, the Z-direction scan of the image sensor is divided into a plurality of times (multiple steps), the relative position of the image sensor and the measured portion is moved after one step, and the image sensor and the subject are moved after the next one step. It can be set to move the position relative to the measurement site.

It is possible to move the relative position of the image sensor and the part to be measured in the X and / or Y directions, and scan the image sensor in the Z direction orthogonal to the X and Y directions, and after scanning the image sensor in the Z direction. , X direction and / or Y direction image sensor can be set to move relative position to the measured part. In this case, for example, after scanning the image sensor on the positive side in the Z direction, the relative position of the image sensor and the part to be measured is moved, and then scanning on the negative side in the Z direction of the easy sensor is performed, and then the image sensor. It can be set to move the position relative to the part to be measured.

The part to be measured in the method is at least one of the bonded wire, the joint portion thereof, and the joint portion to be joined.

In the present invention, the horizontal resolution can be improved, and highly accurate measurement becomes possible. Further, since the amount of one movement of the relative position movement is smaller than the pixel size, the time of one movement is short, and the throughput (the amount that can be processed per unit time) can be improved. In particular, in the case of moving the sensor side, the moving mechanism can be simplified.

It is a simplified overall view of the measuring apparatus of this invention. It is a figure which shows the moving direction of an image sensor. It is a figure which shows the moving order of the photoelectric conversion part of an image sensor. It is a simplified figure which shows various positions of the photoelectric conversion part of an image sensor. It is a simplified figure which shows the moving direction of an image sensor. It is a simplified figure which shows various shapes of the photoelectric conversion part of an image sensor. A CCD image sensor is shown, (a) is a simplified view before moving, and (b) is a simplified view after moving. It is a simplified view of the part to be measured. It is a simplified overall view of the conventional measuring apparatus.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 8.

FIG. 1 shows a measuring device according to the present invention, and this measuring device is a device that measures (detects) the shape, locus, dimensions, bonding quality, etc. of a measured portion S as shown in FIG. The measurement site S is a bonding wire 51, a wire bonding portion 52, a bonding portion 53, and other measurement areas (not shown). That is, as a work having the measured portion S, a substrate or the like to which the bonding wire 51 is connected.

As shown in FIG. 1, the measuring device includes a light source 11 which is monochromatic light or multicolor light, a collimator lens 12, a beam splitter 13, a reference plate 14, an imaging lens 15, and a CCD constituting an imaging means 10. A camera 16 such as a camera or a CMOS camera is provided. When the light is monochromatic light, the light source 11 can be an LED light source such as purple, blue, green, or red, or a laser light source. Further, the multicolor light is light in which a plurality of types of monochromatic colors are mixed. The light emitted from the light source may be white light. When white light is used, other white light sources such as xenon lamps, halogen lamps, mercury lamps, and white LEDs can be adopted. Further, the light may be visible light or other than visible light.

The light emitted from the light source 11 is collimated by the collimator lens 12 and split in two directions by the beam splitter 13. One of the divided lights is applied to the measurement surface of the work W, which is the portion S to be measured, and the other divided light is applied to the reference surface of the reference plate 14. The light reflected from the irradiation of the measurement surface and the reference surface is combined by the beam splitter 13, and the interference light at that time is imaged by the CCD camera 16 via the imaging lens 15. That is, this measuring device is a two-luminous flux interference method.

A camera 16 such as a CCD camera or a CMOS camera includes an image sensor 18 as shown in FIGS. 2A to 2D. The pixel 20 of the image sensor 18 is composed of a photoelectric conversion portion 22 composed of a photodiode (PD) 21 that performs photoelectric conversion and a portion (non-photoelectric conversion portion) 23 other than the photodiode such as a circuit. The CCD camera 16 has a plurality of such image sensors 18 as shown in FIGS. 6A and 6B.

That is, the image sensor 18 has pixels 20 in which the photoelectric conversion portion 22 is opened in an area smaller than one pixel area. In this case, the opening area of the photoelectric conversion portion 22 can be 7% to 30% of the one pixel area. For example, if the pixel 20 is divided into 9 parts with 3 rows and 3 columns, the opening area is about 11% of one image, and if the pixel 20 is divided into 4 parts with 2 rows and 2 columns, the opening area is about 25% of one image. .. When the pixel is finely divided, the aperture area becomes small and it becomes dark (the light receiving efficiency is low). Therefore, it is preferable to divide the pixel into 3 rows and 3 columns or 2 rows and 2 columns. In this way, setting the opening area of the electric conversion portion 22 to 7% to 30% of the one pixel area is stable in production.

The photoelectric conversion portion 22 can be arranged at various positions as shown in FIGS. 2 (a) to 2 (d). Further, FIGS. 3 (a) to 3 (d) show projection views of the image sensor 18 on the side to be measured S. Therefore, in the projection surface 18A, when one pixel 20 is divided into four equal parts (one row and one column) and the photoelectric conversion portion 22 is arranged at the position shown in FIG. 2A, the photoelectric conversion portion 22 is shown in FIG. When the photoelectric conversion portion 22 is arranged at the position shown in FIG. 2B corresponding to the compartment 20a of “1” in a), the photoelectric conversion portion 22 corresponds to the compartment 20a of “1” in FIG. When the photoelectric conversion portion 22 is arranged at the position shown in FIG. 3C, the photoelectric conversion portion 22 corresponds to the section 20a of “1” in FIG. 3C, and when the photoelectric conversion portion 22 is arranged at the position shown in FIG. 22 is arranged in the section 20a of “1” in FIG. 3 (d).

Therefore, the opening area of the photoelectric conversion portion 22 shown in FIG. 2 is about 25% of one pixel 20 of the image sensor 18. Then, the image sensor 18 can move in the XY directions orthogonal to each other via the moving means 25. In this case, the moving means 25 relatively moves the image sensor 18 and the measured portion S, and the amount of pixels is less than one pixel and is a fractional portion excluding the integer portion of the movement amount expressed in pixel units. It is something that shifts. That is, when the relative movement amount in the X direction or the Y direction is 1.5 pix, (1.5-1) pix = 0.5 pix is the shift amount. When the relative movement amount in the X direction or the Y direction is 5.2 pix, (5.2-5) pix = 0.2 pix is the shift amount.

In the case shown in FIG. 2 (a), the photoelectric conversion portion 22 moves from “1” → “2” → “3” → “4” in FIG. 3 (a) and is shown in FIG. 2 (b). In this case, the photoelectric conversion part 22 moves from “1” → “2” → “3” → “4” in FIG. 3 (b), and in the case shown in FIG. 2 (c), the photoelectric conversion part As the 22, it moves from “1” → “2” → “3” → “4” in FIG. 3 (c), and in the case shown in FIG. 2 (d), the photoelectric conversion portion 22 is shown in FIG. Move to "1"-> "2"-> "3"-> "4" in d). As a result, the photoelectric conversion portion 22 can cover the entire pixel 20.

As the moving means 25, for example, a ball screw mechanism, a linear guide mechanism, a cylinder mechanism or the like can be used, and various drive sources thereof include a piezo actuator (piezo motor), an ultrasonic motor, a servo motor, a stepping motor and the like. Can be used.

Further, the work W having the measured portion S is arranged on the stage 26, and the stage 26 can be reciprocated in the Z direction by the Z direction moving means 27. That is, the moving means 25 can reciprocate the stage 26 in a direction (vertical direction) orthogonal to the movement in the XY directions (on the horizontal plane), which is the moving direction of the camera 16. Similar to the moving means 25, the Z-direction moving means 27 can also use, for example, a ball screw mechanism, a linear guide mechanism, a cylinder mechanism, or the like, and its drive source is a piezo actuator (piezo motor) or an ultrasonic motor. , Servo motors, stepping motors and the like can be used. When the part to be measured has an uneven portion that exceeds the interference, the measurement can be made by moving the S side of the part to be measured in the Z direction.

By the way, this measuring device includes a Z-direction scanning means 28 as shown in FIG. The Z-direction scanning means 28 can be configured by a scanning circuit provided in the camera 6 which is an image sensor. In this way, by having the Z-direction scanning means 28, the image of the measured portion S can be acquired while scanning the focal position of the camera from top to bottom in the Z direction, or scanned from bottom to top in the Z direction. However, it is possible to acquire an image of the measured portion S. The Z-direction scanning means 28 can be configured by the Z-direction moving means 27, and the Z-direction moving means 27 can be omitted.

Then, each means 25, 27, 28 is controlled by the control means 30 as shown in FIG. The control means 30 is, for example, a microcomputer in which a ROM (Read Only Memory), a RAM (Random Access Memory), and the like are connected to each other via a bus centering on a CPU (Central Processing Unit). Further, a storage means (not shown) is connected to the control means 30. The storage means includes an HDD (Hard Disc Drive), a DVD (Digital Versatile Disk) drive, a CD-R (Compact Disc-Recordable) drive, an EEPROM (Electronically Erasable and Programmable Read Only Memory), and the like. The ROM stores programs and data executed by the CPU.

Next, a method of measuring the measured portion S of the work W using the measuring device shown in FIG. 1 will be described. In this case, the movement of the image sensor 18 in the XY directions and the Z-direction scanning (Z-scan) are combined for measurement. For example, as the first method, the movement in the XY directions is performed during the Z scan, and as the second method, the movement in the XY directions is performed for each reciprocating movement of the Z scan.

Specifically, when the Z scan is from top to bottom, the first method divides the scan into a plurality of stages, and after scanning for one step or during the scan (even if the movement in the Z direction stops, the Z direction Even if the movement is not stopped, the movement is performed in the XY directions, and after scanning for one step, the movement is performed in the XY directions. This is done until all Z scans are completed. Also, in the first method, the Z scan may be from bottom to top.

The second method is to scan from bottom to top, then move in the XY directions, perform one pitch, then scan from top to bottom, move in the XY directions, perform one pitch, and perform 1 pitch. The entire pixel 20 is covered. Further, after scanning from top to bottom, movement in the XY directions and one pitch may be performed, and then scanning from bottom to top may be performed to move in the XY directions and one pitch. The movements in the X and Y directions (movements of one pitch) in the first and second methods are "1" → "2", as shown in FIGS. 3 (a), (b), (c) and (d). "2" → "3" or "3" → "4".

FIG. 4 shows a case where the photoelectric conversion portion 22 is provided in one section 20a when the image sensor 18 divides one pixel 20 into three rows and three columns as shown in FIG. 5 (a) to 5 (d) show projection views of the image sensor 18 on the side to be measured S. In FIG. 4 (a), the photoelectric conversion part 22 corresponds to the section 20a of “1” in FIG. 5 (a), and in FIG. 4 (b), the photoelectric conversion part 22 corresponds to “2” in FIG. 5 (b). In FIG. 4 (c), the photoelectric conversion portion 22 corresponds to the compartment 20a of FIG. 5 (b), and in FIG. 4 (d), the photoelectric conversion portion 22 corresponds to the compartment 20a of FIG. 5 (b). Corresponding to the compartment 20a of "4" in FIG. 5 (b), in FIG. 4 (e), the photoelectric conversion portion 22 corresponds to the compartment 20a of "5" in FIG. 5 (b), and is shown in FIG. 4 (f). Then, the photoelectric conversion part 22 corresponds to the section 20a of “6” in FIG. 5 (b), and in FIG. 4 (g), the photoelectric conversion part 22 corresponds to the section 20a of “7” in FIG. 5 (b). Correspondingly, in FIG. 4 (h), the photoelectric conversion part 22 corresponds to the section 20a of “8” in FIG. 5 (b), and in FIG. 4 (i), the photoelectric conversion part 22 corresponds to FIG. 5 (b). Corresponds to the section 20a of "9"

5 (a) to 5 (f) show the order of movement in the XY directions when the photoelectric conversion portion 22 corresponds to the position shown in FIG. 4 (a). They move in the order of "1"-> "2"-> "3"-> "4"-> "5"-> "6"-> "7"-> "8"-> "9", respectively. Further, when the photoelectric conversion portion 22 corresponds to the position shown in FIGS. 4 (b) to 4 (f), the movement order in the XY directions can be arbitrarily set within a range in which the entire section 20a can be moved. Is omitted.

By the way, in the above-described embodiment, the opening shape of the photoelectric conversion portion 22 is substantially square, but other shapes as shown in FIG. 6 may be used. That is, it is a substantially rectangular shape in FIG. 6A, a substantially circular shape in FIG. 6B, a substantially oval shape in FIG. 6C, and a substantially hexagonal shape in FIG. 6D. Here, the substantially circular shape is a concept that includes not only a perfect circle but also a shape that is close to a circle to some extent (such as a slightly elliptical shape or a shape having irregularities on the circumference). The abbreviated ellipse includes an actual ellipse and a shape close to an ellipse, and a shape close to an ellipse also includes a compound circle and a shape formed by a circle and a straight line. .. The substantially square is an actual square and a shape substantially close to a square, and includes a substantially rectangle having rounded vertices and the like. The substantially rectangular shape is an actual rectangle and a shape substantially close to a rectangle, and includes a substantial rectangle having rounded vertices and the like. The substantially hexagon is an actual regular hexagon and a shape substantially close to a hexagon, and also includes a substantially hexagon having rounded vertices and the like.

The photoelectric conversion portion 22 of each of the above embodiments is preferably set so as to open in an area smaller than the area of one pixel 20. Further, even if each photoelectric conversion portion 22 is composed of the entire PD 21, as shown in FIG. 2A, by providing the light receiving surface of the photoelectric conversion portion 22 with the light receiving surface 24, the original light receiving surface of the PD 21 The area may be reduced to provide the photoelectric conversion portion 22. The opening area of the photoelectric conversion portion 22 is preferably an area of 7% or more and 30% or less of the one pixel area.

When the light-shielding portion 24 is provided, it can be composed of, for example, a paint (resin) containing a black pigment (carbon black), a metal vapor deposition film, a metal plate (etching or machining), or the like. As described above, the light-shielding portion 24 can be provided with various simple configurations.

Since the image sensor 18 having pixels having an open photoelectric conversion portion smaller than the area of one pixel 20 is used, the apparent pixel size of the image sensor 18 can be reduced and the horizontal resolution can be improved. Moreover, the portion (missing portion) that cannot be measured due to the reduced pixel size can be complemented by the relative movement between the image sensor 18 and the portion to be measured.

That is, in the present invention, the horizontal resolution can be improved and highly accurate measurement becomes possible. Further, since the amount of one movement of the relative position movement is smaller than the pixel size, the time of one movement is short, and the throughput (the amount that can be processed per unit time) can be improved. In particular, in the case of moving the sensor side, the moving mechanism can be simplified.

Further, since the relative position movement of the image sensor 18 and the measured portion S in the X direction and / or the Y direction and the scanning of the image sensor 18 orthogonal to the X direction and the Y direction in the Z direction are possible, the pixels of the camera Height data for each can be obtained, brightness can also be obtained according to the reflectance of the part S to be measured, and a brightness image can also be obtained. Therefore, it is possible to measure various shapes and dimensions.

In this embodiment, 3D data included in the bonding wire 51, the wire bonding portion 52, the wire bonded portion 53, and other measurement regions can be acquired. Therefore, from this 3D data, the shape, locus, dimensions, joint quality, and the like can be observed.

By the way, although one image sensor 18 has been described, as shown in FIG. 7, a plurality of image sensors 18 may be provided. In this case, a plurality of image sensors 18 form a line sensor in which a plurality of image sensors 18 are arranged in a row. In the state of FIG. 7A, the range of H1 corresponding to the photoelectric conversion portion 22 can be observed (measured), and the range between adjacent H1 and H1 cannot be observed. Therefore, by moving the plurality of image sensors by one pitch in the direction of the arrow (the amount of movement corresponding to the photoelectric conversion portion in the range between H1 and H1), as shown in FIG. 7B, between H1 and H1. It is possible to form an observable (measurable) range of H2. Therefore, there is no omission of observation.

When a plurality of image sensors 18 are provided, the number of image sensors 18 is not limited to those arranged side by side in one row as shown in FIG. 6, and the plurality of image sensors 18 are area sensors arranged in a matrix (plural matrix). You may.

Further, in the above-described embodiment, the scan in the Z direction is performed, but as another embodiment, such a scan in the Z direction may not be performed.

The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, in the above-described embodiment, when the card is moved in the XY directions, it can be moved to the adjacent compartments 20a at a constant pitch. Although it is a movement, it is not necessary to move it at a constant pitch depending on the shape of the measured portion S of the work or the like. That is, when the compartment 20a is provided as shown in FIG. 5, the compartment 20a may be moved from "1" to "3" in FIG. 5A. Further, although it was moved in the X direction or the Y direction in the above embodiment, it may be moved in a direction inclined with respect to the X direction and the Y direction.

As the two-luminous flux interferometer used in the measuring device according to the present invention, the Michelson interference method was used in the above embodiment, but the Mirau interference method may be used.

By the way, in the present measuring device and the measuring method, the one that observes a field of view larger than that of the sensor 18 (an optical system having an optical magnification of 1 times or less) is most suitable for obtaining the action and effect peculiar to the present invention. However, it may be the one that observes the same field of view as the sensor 18 or the one that observes a field of view smaller than that of the sensor 18.

10 Imaging means 11 Light source 14 Reference plate 16 Camera 18 Image sensor 20 pixels 21 Photoelectric conversion part 25 Moving means 27 Z-direction moving means 28 Z-direction scanning means 51 Bonding wire 52 Wire bonding part 53 Bonded part S Measured part

Claims (15)

The light from the light source is divided in two directions, one divided light is applied to the part to be measured, and the other divided light is applied to the reference plate to synthesize the reflected light reflected from the part to be measured and the reference plate. It is a measuring device using a two-light focusing interferometer having an imaging means for imaging the interference light.
The imaging means includes an image sensor having pixels in which the photoelectric conversion portion is opened in an area smaller than one pixel area, and the position moving means is used to relatively move the image sensor and the portion to be measured. A measuring device characterized in that the pixels are shifted by the amount of a fractional portion excluding the integer portion of the movement amount expressed in pixel units, which is less than one pixel. The measuring device according to claim 1, wherein the opening of the photoelectric conversion portion of the image sensor is formed by providing a light-shielding portion in the pixel. The measuring device according to claim 1, wherein the opening of the photoelectric conversion portion of the image sensor is formed by a light receiving surface of a photodiode. The measuring device according to any one of claims 1 to 3, wherein the aperture area of the photoelectric conversion portion of the image sensor is 7% or more and 30% or less of the pixel area. The measurement according to any one of claims 1 to 4, wherein the opening shape of the photoelectric conversion portion of the image sensor is any one of substantially circular, substantially elliptical, substantially square, and substantially rectangular. apparatus. The measuring device according to any one of claims 1 to 5, wherein the position moving means is composed of a piezoelectric actuator that moves the image sensor with respect to the part to be measured. The measuring device according to any one of claims 1 to 6, wherein the light emitted from the light source has a single color or a plurality of colors. The measuring apparatus according to any one of claims 1 to 7, wherein the measurement portion is at least one of a bonded wire, a joint portion thereof, and a joint portion to be joined. The light is divided in two directions, one divided light is applied to the part to be measured, and the other divided light is applied to the reference plate, and the reflected light reflected from the part to be measured and the reference plate is synthesized and the light is synthesized. It is a measurement method using the two-light convergence interferometry that captures the interference light.
An integer portion of the amount of movement expressed in pixel units, which is less than one pixel by relatively moving the image sensor having an image in which the photoelectric conversion part has an opening in an area smaller than one pixel area and the part to be measured. A measurement method characterized in that the image is imaged with an image sensor by shifting the image by the amount of a fractional portion excluding. The measuring method according to claim 9, wherein the relative movement between the image sensor and the part to be measured is set to a constant pitch. The measuring method according to claim 9, wherein the relative movement between the image sensor and the part to be measured is set to an arbitrary indefinite pitch. The measuring method according to any one of claims 8 to 10, wherein only the relative position movement between the image sensor in the X direction and / or the Y direction and the measured portion is performed. It is possible to move the relative position of the image sensor in the X and / or Y directions and the part to be measured, and scan the image sensor in the Z direction orthogonal to the X and Y directions, and the image sensor is being scanned in the Z direction. The measuring method according to any one of claims 8 to 10, wherein the image sensor is relatively moved in the X direction and / or the Y direction. It is possible to move the relative position between the image sensor in the X and / or Y directions and the part to be measured, and scan the image sensor in the Z direction orthogonal to the X and Y directions, and after scanning the image sensor in the Z direction. The measuring method according to any one of claims 8 to 10, wherein the image sensor is moved in the X direction and / or the Y direction. The measuring apparatus according to any one of claims 8 to 14, wherein the measurement portion is at least one of a bonded wire, a joint portion thereof, and a joint portion to be joined.

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