TW202235815A - Measuring device - Google Patents

Abstract

The present invention provides a high-speed and high-precision measuring device. A measuring device 100 measures a distance up to an object and includes: a light source 110 projecting light; a reflecting mirror 129; a beam splitter 121 dividing the light projected from the light source into a measurement light directed to the object and a reference light directed to the reflecting mirror; an event based camera 130 detecting a change of a received luminance value for an interference waveform of the reference light reflected by the reflecting mirror and the measurement light reflected by the object to obtain data; a processing part 140 measuring a distance up to the object based on the data of the interference waveform; and a control mechanism controlling an amount of light received by the event based camera to vary.

Description

measuring device

The present invention relates to a measuring device.

In recent years, in the multi-stage stacking of semiconductor wafers, the assembly of rotary actuators for hard disk drives, the assembly of camera modules built in smartphones (smartphone), and the assembly of light-emitting diodes (Light Emitting Diode, LED) light distribution control, etc., require high precision for the alignment of parts.

A measuring device using an optical system is known as a device for measuring and inspecting a measurement object including these components.

Patent Document 1 discloses a technique related to an interferometric shape measuring device. In this shape measuring device, an interference pattern of a received light amount that varies depending on the difference between the optical path length of the measurement light and the reference light is specified, and the surface shape of the object to be measured is acquired based on the interference pattern. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2018-63153

[Problem to be Solved by the Invention]

However, the shape measuring device disclosed in Patent Document 1 has problems such as the need to move and measure multiple points, or the acquisition and processing of a huge amount of data, which prevents high-speed measurement.

Therefore, an object of the present invention is to provide a high-speed and high-precision measuring device. [Means to solve the problem]

A measuring device according to an aspect of the present invention measures the distance to an object, and includes: a light source, projection light; a reflector; a beam splitter, which divides the light projected from the light source into measurement light directed to the object and a guide reflector. The reference light; the event camera (event based camera), for the interference waveform of the reference light reflected by the mirror and the measurement light reflected by the object, detects the change of the received brightness value to obtain data; the processing part, based on the interference waveform data to measure the distance to the object; and a control mechanism to control the amount of light received by the event camera to change.

According to this aspect, the event camera detects the change in the brightness value received with respect to the interference waveform of the reference light reflected by the mirror and the measurement light reflected by the object in each pixel arranged, and at the timing of the detection Since the data of the interference waveform portion is obtained, the data required for measuring the distance to the object can be obtained, and the amount of data to be obtained can be reduced. That is, the measuring device can measure an object at high speed and with high precision.

In the above aspect, the control means may include a drive unit for driving the mirror so that the difference between the optical path length of the measurement light and the optical path length of the reference light changes.

According to this aspect, the measuring device can measure the target object at high speed and with high precision by using the white interferometric measuring method.

In the above aspect, the control mechanism may use a wavelength swept light source as the light source in such a manner that the wavelength of the light projected from the light source changes continuously.

According to this aspect, the measurement device can measure the object at high speed and with high precision by using the measurement method of the wavelength scanning method.

The above-mentioned aspect may also include: a logarithmic amplifier (logarithmic amplifier), which uses the increase and decrease of the light received by the event camera as polarity data, and calculates the light received by the event camera based on the accumulation of the polarity data.

According to this aspect, the logarithmic amplifier can use the increase and decrease of the amount of light received by the event camera as polarity data to capture minute changes at high speed, thereby shortening the shooting time.

In the above aspect, it may further include: an adjustment unit, which can adjust the amount of data processed by the event camera.

According to this aspect, since the adjustment unit adjusts the amount of data processed by the event camera, even when an event occurs simultaneously in a plurality of pixels, the event camera can properly process it.

In the above aspect, the adjustment unit may have a Region Of Interest (ROI) function for reading data of a predetermined part of the region.

According to this aspect, by using the ROI function, an area required for measurement of an object is set as an area for reading data, so that the object can be measured more appropriately.

In the above aspect, the adjusting unit may also include: a light cutting unit configured to guide the light irradiated on a predetermined part of the area to the event camera, and not guide the light irradiated on the area other than the part of the area to the event camera. event camera.

According to this aspect, the light cutting unit configured to guide the light irradiated on a predetermined part of the area to the event camera and not guide the light irradiated on the area other than the part of the area to the event camera is arranged. camera, so the object can be measured more appropriately for the area to be measured in the object.

In the above aspect, the light-cut portion may also include a liquid crystal panel.

According to this aspect, a liquid crystal panel can be used to form a light-shielded section having a transmission area that transmits light irradiated on a predetermined partial area, and a light-shielding area that blocks light in areas other than the partial area.

In the above-mentioned aspect, the cutout unit may be arranged on a common optical path of the measurement light and the reference light.

According to this aspect, since the optical paths of the measurement light and the reference light are under the same condition, the possibility of affecting the interference accuracy can be reduced.

In the above-mentioned aspect, the predetermined part of the area may be preset according to the shape of the object.

According to this aspect, according to the shape of the object, the area that is the characteristic part of the object and the area to be measured are set as a predetermined part of the area that reads data or transmits light, so that the object can be measured more appropriately. . [Effect of the invention]

According to the present invention, a high-speed and high-precision measuring device can be provided.

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the accompanying drawings. In addition, the embodiment described below is just a specific example for carrying out the present invention, and does not limitatively interpret the present invention. In addition, in order to facilitate understanding of the description, the same reference numerals may be attached to the same constituent elements as much as possible in the respective drawings, and overlapping descriptions may be omitted.

＜First Embodiment＞ [Structure of measuring device] FIG. 1 is a schematic diagram showing the configuration of a measuring device 100 according to a first embodiment of the present invention. As shown in FIG. 1 , the measuring device 100 includes a light source 110 , an optical system 120 , an event camera 130 and a processing unit 140 . The optical system 120 includes a beam splitter 121 , a plurality of lenses 122 - 126 and a plurality of mirrors 127 - 129 . Furthermore, a driving unit 150 (control mechanism) for driving the mirror 129 is included.

The light source 110 projects light L0. The light source 110 is typically a white light source, for example, may also be a super luminescent diode (SLD) light source. SLD light source is a broadband light source with two characteristics of light-emitting diode (LED) and semiconductor laser (LD). The coherence is higher than that of LED light source and lower than that of laser light. Furthermore, the light source 110 emits light with a constant intensity, and the intensity of the light does not change.

In addition, for the light source 110, for example, a halogen lamp, a white LED, and a white laser light source can also be used.

The light L0 projected from the light source 110 passes through the lens 122 (for example, a collimating lens), is parallelized, and is reflected by the reflector 127 . The light L0 reflected by the mirror 127 is then condensed by passing through the lens 123 , and enters the beam splitter 121 .

The beam splitter 121 splits the light L0 into the measurement light L1 guided to the object T and the reference light guided to the mirror 129 . In other words, part of the light L0 is reflected by the beam splitter 121 (measurement light L1 ), and the remaining part of the light L0 passes through the beam splitter 121 (reference light L2 ).

Regarding the lens 124 (for example, an objective lens), the measurement light L1 is parallelized by passing through the lens 124 . Then, the measurement light L1 is irradiated on the region of the object T, and a part of the measurement light L1 reflected by the object T is condensed by passing through the lens 124 and enters the beam splitter 121 again.

On the other hand, the reference light L2 passed through the beam splitter 121 passes through the lens 125 , is parallelized, is reflected by the reflection mirror 128 , and is irradiated to the reflection mirror 129 . The reflection mirror 129 is a so-called reference mirror.

Then, the reference light L2 reflected by the mirror 129 is reflected by the mirror 128 , is condensed by passing through the lens 125 , and enters the beam splitter 121 again.

The measurement light L1 reflected by the object T and entering the beam splitter 121 interferes with the reference light L2 reflected by the mirror 129 and enters the beam splitter 121, and passes through the lens 126 as interference light L3, and is parallelized and guided. To event camera 130 . The event camera 130 acquires data by detecting the change of the received brightness value with respect to the interference waveform L3. The data acquired by the event camera 130 will be described later.

The processing unit 140 measures the distance to the object T based on the data of the interference waveform L3 acquired by the event camera 130 , the position of the mirror 129 (the optical path length of the reference light L2 ) controlled by the drive unit 150 described later, and the like.

The drive unit 150 (control mechanism) is, for example, an actuator including a voice coil motor (VCM), and moves the mirror 129 along the optical axis so that the optical path length of the reference light L2 changes.

In this way, by changing the optical path length of the reference light L2, the difference between the optical path length of the measurement light L1 and the optical path length of the reference light L2 is changed to generate an interference waveform. Specifically, the interference fringe can be observed centering on the position where the phase difference is 0, and when the optical path lengths of the measurement light L1 and the reference light L2 match, an interference waveform is generated. A method of measuring an object using this interference waveform is, for example, a measurement method called a white interferometric method.

[About event camera] Here, the event camera 130 serving as an imaging element will be described. The event camera 130 detects the change of the received luminance value in each pixel arranged, and photographs the interference waveform of the part (pixel) where the change is detected at the timing of the detection, and obtains the polarity, time and coordinates of the luminance change data of.

FIG. 2 is a schematic diagram showing a state of acquiring data by an event camera 130 serving as an imaging device. As shown in FIG. 2, the event camera 130 detects the change of the received luminance value in each pixel arranged, and acquires the data of the interferometric waveform part required for measurement at the timing of the detection, and in other parts , do not fetch data.

Previously, the Complementary Metal-Oxide-Semiconductor (CMOS) used as an imaging element obtained all the data of each pixel, and the amount of data was huge. In other words, the event camera 130 acquires the data of the interference waveform portion required for measuring the distance to the target T more efficiently than the CMOS imaging element.

As mentioned above, the event camera 130 is used as the imaging element to detect the change of the received luminance value in each pixel arranged, and obtain the data of the interference waveform part at the timing of the detection, so that the measurement can be obtained up to the target object. The information required for the distance up to T, and reduce the amount of acquired information.

FIG. 3 is a diagram showing how the surface shape (distance to the surface) of an object is measured by the measurement device 100 using the event camera 130 as an imaging element. As shown in FIG. 3 , for the measurement of die bonding and camera modules, the event camera 130 acquires the data required for the measurement at multiple points (overall), and efficiently processes it at high speed (reading, etc.) The required information. As a result, the measurement device 100 can perform high-speed and high-precision measurement of an object.

Furthermore, the event camera 130 may include a logarithmic amplifier that captures minute changes in the amount of received light in order to detect changes in received luminance values in each of the arrayed pixels and acquire data on the interference waveform portion at the timing of the detection.

FIG. 4 is a diagram showing a change (increase or decrease) in the amount of light received by the event camera 130 as bipolarity, and an envelope curve based on the accumulation of the bipolarity data. As shown in FIG. 4 , the logarithmic amplifier captures minute changes in the amount of light received by the event camera 130 , and sets the increase or decrease of the changes as bipolar data. Then, based on the accumulation of the polarity data, the envelope of the light-receiving amount distribution is determined, and the light-receiving amount acquired by the event camera 130 is calculated.

In this way, by including a logarithmic amplifier in the event camera 130 , it is possible to capture minute changes in the amount of light received by the event camera 130 at high speed, so that the imaging time can be shortened.

Furthermore, as mentioned above, the event camera 130 detects the occurrence of events such as changes in the amount of received light (brightness value) in each of the arranged pixels. In addition, the event camera 130 acquires the data of the interference waveform part in the pixel where the event is detected. Here, an adjustment unit may be included, which can adjust the amount of data to be processed according to the capacity and performance of the event camera 130 even when events occur simultaneously in a plurality of pixels, so that processing can be performed appropriately.

[About the ROI function] FIG. 5 is a diagram showing an example of an adjustment unit capable of adjusting the amount of data processed by the event camera 130 using the ROI function. As shown in FIG. 5 , five rectangular areas 0 to 4 for reading data are set in the maximum effective imaging area, which is an area that can be captured by the event camera 130 , and are set so as not to read data in other areas.

In this way, the event camera 130 acquires data by detecting changes in received luminance values (occurrence of events) in the pixels arranged in the rectangular area 0 to the rectangular area 4, but in other areas, it does not matter whether an event occurs or not. Get information. The event camera 130 may also not monitor whether an event occurs in the other area.

Here, five rectangular areas 0 to 4 are set as an example as the area for reading data, but the present invention is not limited thereto. For example, four or less or six or more rectangular areas may be set.

In addition, as the area for reading data, the size and shape of each rectangular area may be the same or different, and may have a shape other than a rectangle.

The area for reading data (for example, number, shape, and position, etc.) may be appropriately set according to the type, capacity, and performance of the event camera 130, and the type and shape of the object to be measured, etc., and the setting may be made by the user in advance. It can also be set by teaching.

FIG. 6 is a diagram showing an example of a situation where the area where data is to be read is taught using the event camera 130 . For example, the event camera 130 is used to teach the area where the data is to be read so that the object T is measured as the measurement device 100 .

As shown in FIG. 6 , with the event camera 130 , for all the pixels in the maximum effective shooting area, the white interferometric measurement method is used to acquire data. For example, depending on the type, capacity, and performance of the event camera 130 , sometimes data cannot be simultaneously obtained from all pixels, so data is sequentially obtained in units of the number of pixels that can be obtained simultaneously. Furthermore, the purpose here is to teach the region where the data is to be read, so when the data acquired by the event camera 130 does not require detailed data, all the pixels may not be used as the object. For example, as the data acquired by the event camera 130 , it is also possible to acquire the data in a thinned-out manner for every several pixels.

In addition, based on the data acquired by the event camera 130 , three-dimensional (Three Dimension, 3D) data of the object T is generated, and an area to read the data is set with reference to the 3D data. The area where the data is read can be set by the user, for example, as a characteristic portion of the object T, or as a measurement target area, or can be automatically set for an area having a predetermined height.

Furthermore, the white interferometric measurement method is used here, and the event camera 130 is used to obtain data for all pixels in the maximum effective shooting area, but in this teaching, CMOS can also be used as the imaging element.

For example, what is necessary is just to arrange|position a half mirror etc. so that the CMOS imaging element arrange|positioned separately irrespective of the event camera 130 can receive the interference waveform L3 demonstrated using FIG. Thus, during the teaching, the CMOS imaging element receives the interference waveform L3 reflected by the half mirror.

In addition, if the measurement method of the white interferometric method is used, and the CMOS imaging element is used to acquire data for all the pixels in the maximum effective imaging area, then the 3D data of the object T is generated in the same way as described using FIG. 6 , and An area for reading data is set with reference to the 3D data.

Furthermore, as a method of setting the region for reading data by teaching, for example, it is conceivable to import schematic information such as computer-aided design (CAD) data of the object T, and set the reading area by referring to the schematic information. data area.

FIG. 7 is a diagram showing an example of a situation in which an area for reading data is taught with reference to the drawing information. As shown in FIG. 7 , the CAD data of the object T to be measured by the measuring device 100 is imported as the drawing information, and the imported drawing information is referred to to set the area from which the data is read. The area where the data is read can be set by the user, for example, as a characteristic portion of the object T, or as a measurement target area, or can be automatically set for an area having a predetermined height.

In addition, it is also possible to generate a distance image (image data whose height is the pixel value), and set the area to read the data while referring to the distance image. Compared with the case where the operation is performed as coordinate data on the 3D space, there is an effect that the calculation cost of the display processing can be reduced.

Moreover, it is also possible to perform rendering (rendering) processing (generating a simulated image by optical simulation) based on the 3D data to generate a shaded image, and refer to the shaded image for region setting. Thereby, there is an effect of reducing the calculation cost of display processing.

[about the shading department] FIG. 8 is a diagram showing an example of using a light-shielding unit as an adjustment unit capable of adjusting the amount of data processed by the event camera 130 . As shown in FIG. 8 , in the optical system 120 , on the optical path of the light ( L0 , L1 , L2 ) projected from the light source 110 , a light shielding portion including a region for transmitting the light and a region for shielding the light is arranged. As shown in FIG. 8 , when light is irradiated to the light irradiation region, four transmission regions are set as regions through which the light passes, and light-shielding regions are set to shield the light in the other regions.

Thereby, the event camera 130 receives the light that has passed through the transmission area, so among the plurality of pixels arranged in the event camera 130, for the pixels arranged corresponding to the transmission area, a change in the received luminance value (event occurrence) is detected. ) to obtain information. On the other hand, the event camera 130 does not receive light shielded by the light-shielding area, so among the plurality of pixels arranged in the event camera 130 , the pixels arranged corresponding to the light-shielding area do not need to monitor whether an event occurs.

Here, four circular transmission regions are set as an example as the region through which light is transmitted, but the invention is not limited thereto. For example, three or less or five or more transmission regions may be set.

Moreover, the size and shape of each transmission area may be the same or different, and may be other than circular (eg, elliptical, oblong, rectangular, etc.), and may be appropriately set according to the shape of the object to be measured.

The transparent area (for example, the number, shape, and position) can be appropriately set according to the type, capacity, and performance of the event camera 130, and the type and shape of the object to be measured. This setting can be set by the user in advance. It can also be set by teaching.

Furthermore, regarding the setting of the transmission area, the above-mentioned method of teaching the area for reading data can be applied. For example, for the data-reading area shown in FIG. 6 and FIG. 7 , as for the light-shielding portion, it only needs to set the area corresponding to the data-reading area as the transmission area, or set other areas as the light-shielding area. .

Furthermore, such a light-shielding portion including a transmissive region and a light-shielding region can also be realized using a liquid crystal panel, for example.

Here, the liquid crystal panel includes a polarizing filter (vertical), a glass substrate (individual electrodes), liquid crystal sandwiched by an alignment layer, a glass substrate (common electrode), and a polarizing filter (horizontal). The linearly polarized light cannot pass through the polarizing filter (horizontal) while maintaining the polarization direction (blocking state). On the other hand, if the liquid crystal sandwiched by the alignment layer bends the polarization direction of the light by 90 degrees, it can pass through the polarizing filter (horizontal) (non-shielding state). The electrodes of the glass substrate (individual electrode) and the glass substrate (common electrode) are provided so as to switch between a light-shielding state and a non-light-shielding state for the liquid crystal.

FIG. 9 is a schematic diagram showing a configuration in which a light shielding unit is arranged in the measurement device 100 shown in FIG. 1 . As shown in FIG. 9 , a light shielding unit 160 is disposed between the lens 122 and the reflection mirror 127 .

Moreover, the location where the light shielding portion 160 is arranged is not limited to between the lens 122 and the reflector 127, for example, it can also be between the light source 110 and the lens 122, between the reflector 127 and the lens 123, between the lens 123 and the beam splitter 121 , between the beam splitter 121 and the lens 126, between the lens 126 and the event camera 130, etc., as long as they are on the common optical path of the measurement light L1 and the reference light L2 in the optical system 120 (optical paths of the light L0 and the light L3) That's it.

By arranging the light-shielding part 160, there is a possibility that the irradiated light may be polarized and diffracted by the liquid crystal, and the state may change. The optical path of L2 becomes the same condition, so the possibility of affecting the interference accuracy can be reduced.

Here, a liquid crystal panel has been described as an example of a light-shielding section including a transmissive area and a light-shielding area. The light in other areas is guided to the event camera 130 , which can also be realized by using a digital micromirror device (Digital Micromirror Device, DMD).

For example, DMD is used for the mirror 127 constituting the measurement device 100 shown in FIG. 1 . The DMD reflects light irradiated to a predetermined part of the area, and absorbs light irradiated to areas other than the part of the area. That is, the light irradiated on a predetermined part of the area can be reflected and incident on the mirror 123 , and finally guided to the event camera 130 .

In this way, the liquid crystal panel and the DMD guide the light irradiated on a predetermined part of the area to the event camera 130, and block or absorb the light irradiated on the area other than the part of the area so as not to guide the light to the event camera 130. way to cut. That is, it can be called a light-cut portion that cuts a part of irradiated light.

As mentioned above, according to the measurement device 100 of the first embodiment of the present invention, the event camera 130 is used as the imaging element, and further, a small change in the amount of received light is appropriately captured by a logarithmic amplifier, and the ROI function and the light shielding unit 160 are used to appropriately capture Adjust the amount of data that event camera 130 processes. As a result, the measuring device 100 can measure the object T more appropriately at high speed and with high precision.

Furthermore, in this embodiment, the optical system 120 includes a beam splitter 121, a plurality of lenses 122-126, a plurality of mirrors 127-129, etc., as shown in FIGS. 1 and 9, but is not limited thereto. For example, as long as the light L0 projected by the light source 110 can be separated into the measurement light L1 and the reference light L2, the event camera 130 finally receives the interference light of the measurement light L1 and the reference light L2 reflected by the object and the mirror, and white interference can be realized. The measurement method of the mode can constitute any optical system.

Furthermore, in this embodiment, the ROI function and the light-shielding unit 160 are cited as an example of an adjustment unit capable of adjusting the amount of data processed by the event camera 130, and teaching of the area for reading data, the transmission area, and the light-shielding area, etc., is performed. description, but not limited to. For example, it can also be set in such a way that the number of pixels of the event camera 130 is reduced (reduced resolution), and data can be acquired even if an event occurs in all pixels at the same time.

[Application example] Fig. 10 is a schematic diagram showing the configuration and functions of a measurement device 100A to which the measurement device 100 according to the first embodiment of the present invention is applied. As shown in FIG. 10 , measurement device 100A includes light source 110 , optical system 120A, event camera 130 , and CMOS imaging element 170 . 10 schematically shows, but the measurement device 100A differs from the measurement device 100 shown in FIG. 1 in that a CMOS imaging element 170 and a half mirror 171A are added.

The measurement device 100A basically measures the object T by the white interference measurement method as described in the measurement device 100 . The event camera 130 functions as an imaging device that acquires data in the Z-axis direction on the object T as described in the measurement device 100 .

Furthermore, in the measurement device 100A, the CMOS imaging element 170 receives the light reflected by the half mirror 171A, and acquires image data of the object T. More specifically, the CMOS imaging element 170 functions as an imaging element that acquires an image of the object T by measurement on the XY-axis plane.

As described above, according to the measurement device 100A, by fusing the image acquired by the CMOS imaging element 170 with the measurement method of the white interferometry method using the event camera 130, it is possible to measure the object T with one sensor. Realize the measurement of XYZ coordinate axis.

Furthermore, the event camera 130 can also be used to achieve the same function as the CMOS imaging element 170 . The event camera 130 detects a change in brightness, but there is also a type that outputs not only the polarity of the change in brightness but also the amount of change in brightness. In this case, the luminance information can be restored by performing integration processing.

Furthermore, it is also possible to use the above-mentioned ROI function and the light cut unit in combination. Multiple ROI regions obtained by dividing the screen can be sequentially switched and photographed, and synthesized to form a single image.

In this way, if the event camera 130 is used to achieve the same function as the CMOS imaging element 170, it is not necessary to newly install the CMOS imaging element 170, and the structure can be simplified.

Furthermore, in the measurement device 100A, the logarithmic amplifier, the ROI function, the light shielding unit 160 and the like applied in the measurement device 100 can also be applied.

<Second Embodiment> Next, in a second embodiment of the present invention, a measurement device using a wavelength-sweeping light source as a control means that controls so as to change the amount of light received by the event camera will be described. In addition, in this embodiment, the structure which differs from 1st Embodiment of this invention mainly is demonstrated in detail, and the description about the item common to 1st Embodiment is abbreviate|omitted or simplified.

Fig. 11 is a schematic diagram showing the configuration of a measuring device 200 according to a second embodiment of the present invention. As shown in FIG. 11 , the measuring device 200 includes a light source 210 , an optical system 120 , an event camera 130 and a processing unit 140 . The optical system 120 includes a beam splitter 121 , a plurality of lenses 122 - 126 and a plurality of mirrors 127 - 129 .

In the measurement device 100 according to the first embodiment of the present invention shown in FIG. 1 , as a control mechanism that controls the amount of light received by the event camera 130 to change, it includes a driving unit 150 that drives the mirror 129. By using The difference between the optical path length of the measurement light L1 and the optical path length of the reference light L2 changes to generate an interference waveform, and the object T is measured by the white interference method.

In the measurement device 200 of the present embodiment, as the control mechanism that controls the amount of light received by the event camera 130 to change, a wavelength scanning light source is used as the light source 210, and by continuously changing the wavelength of light projected from the light source 210 Accordingly, an interference waveform of the measurement light L1 and the reference light L2 is generated, and the object T is measured by a measurement method called a wavelength scanning method.

The light source 210 can use, for example, Micro Electro Mechanical Systems-Vertical Cavity Surface Emitting Laser (MEMS-VCSEL), distributed feedback (DFB) laser and superstructure grating distributed Bragg A reflector (Super Structure Grating-Distributed Bragg reflector, SSG-DBR) laser, etc. is used as a wavelength scanning light source. In addition, the light source 210 emits light with a constant intensity similarly to the light source 110 of the measurement device 100 of the first embodiment, and the light emission intensity does not change.

MEMS-VCSEL uses MEMS to drive the resonant mirror to change the laser oscillation wavelength (wavelength scanning). DFB laser performs wavelength scanning by changing the driving current of the laser diode. SSGDBR uses two resonant mirrors A diffraction grating called a distributed reflector is formed, and wavelength scanning is performed by injecting current.

The event camera 130 detects the received luminance value of the interference waveform L3 of the measurement light L1 and the reference light L2 generated by changing the wavelength of the light projected from the light source 210 as described in the first embodiment of the present invention. Changes to obtain information.

The processing unit 140 measures the distance to the object T based on the data of the interference waveform L3 acquired by the event camera 130 , the wavelength (frequency) of light projected from the light source 210 , and the like.

As described above, according to the measurement device 200 of the second embodiment of the present invention, when the wavelength scanning light source is used as the light source 210 to measure the object T by the measurement method of the wavelength scanning method, the event camera 130 is used as the imaging element, and the By detecting the change of the received luminance value in each pixel and acquiring the data of the interference waveform part at the timing of the detection, the data required for measuring the distance to the object T can be obtained and the amount of data obtained can be reduced.

Furthermore, the logarithmic amplifier, the ROI function, the light shielding unit 160 and the like applied to the measurement device 100 according to the first embodiment of the present invention can also be applied to the measurement device 200 of the present embodiment.

Furthermore, by adding the CMOS imaging device 170 and the like to the measuring device 200 of this embodiment as in the measuring device 100A described using FIG. The measurement method of the wavelength scanning method of the camera 130 is fused, so that the measurement of the XYZ coordinate axes can be realized by using one sensor for the object T.

The embodiments described above are for facilitating understanding of the present invention, and are not intended to limitatively interpret the present invention. Each element included in the embodiment and its arrangement, material, condition, shape, size, etc. are not limited to the examples, and can be changed appropriately. Furthermore, the structures shown in different embodiments may be partially replaced or combined with each other.

[Note] A measuring device 100, 200 measures a distance to an object and includes: Light source 110, 210, projecting light; Mirror 129; The beam splitter 121 splits the light projected from the light source into measurement light directed to the object and reference light directed to the mirror; The event camera 130 is used to detect the change of the received luminance value and obtain data for the interference waveform of the reference light reflected by the mirror and the measuring light reflected by the object; The processing unit 140 measures the distance to the object based on the data of the interference waveform; and The control means 150 is controlled so as to change the amount of light received by the event camera.

100, 100A, 200: measuring device 110, 210: light source 120, 120A: optical system 121: beam splitter 122～126: Lens 127～129: reflector 130:Event Camera 140: processing department 150: drive unit (control mechanism) 160: shading part 170: CMOS imaging element 171A: half mirror L0～L3: light T: object

FIG. 1 is a schematic diagram showing the configuration of a measuring device 100 according to a first embodiment of the present invention. FIG. 2 is a schematic diagram showing a state of acquiring data by an event camera 130 serving as an imaging device. FIG. 3 is a diagram showing how the surface shape (distance to the surface) of an object is measured by the measurement device 100 using the event camera 130 as an imaging element. FIG. 4 is a diagram showing a change (increase or decrease) in the amount of light received by the event camera 130 as bipolarity, and an envelope curve based on the accumulation of the bipolarity data. FIG. 5 is a diagram showing an example of an adjustment unit capable of adjusting the amount of data processed by the event camera 130 using the ROI function. FIG. 6 is a diagram showing an example of a situation where the area where data is to be read is taught using the event camera 130 . FIG. 7 is a diagram showing an example of a situation in which an area for reading data is taught with reference to the drawing information. FIG. 8 is a diagram showing an example of using a light-shielding unit as an adjustment unit capable of adjusting the amount of data processed by the event camera 130 . FIG. 9 is a schematic diagram showing a configuration in which a light shielding unit is arranged in the measurement device 100 shown in FIG. 1 . Fig. 10 is a schematic diagram showing the configuration and functions of a measurement device 100A to which the measurement device 100 according to the first embodiment of the present invention is applied. Fig. 11 is a schematic diagram showing the configuration of a measuring device 200 according to a second embodiment of the present invention.

100: Measuring device

110: light source

120: Optical system

121: beam splitter

122~126: lens

127~129: Mirror

130:Event Camera

140: processing department

150: drive unit (control mechanism)

L0~L3: light

T: object

Claims (10)

A measuring device that measures a distance up to an object and includes: light source, projected light; Reflector; a beam splitter for splitting the light projected from the light source into measurement light directed to the object and reference light directed to the mirror; The event camera is used to detect the change of the received brightness value for the interference waveform of the reference light reflected by the mirror and the measurement light reflected by the object to obtain data; a processing unit that measures a distance to the object based on the data of the interference waveform; and The control mechanism controls the amount of light received by the event camera to change. The measuring device as claimed in claim 1, wherein The control means includes a drive unit for driving the mirror so that a difference between the optical path length of the measurement light and the optical path length of the reference light changes. The measuring device as claimed in claim 1, wherein The control means uses a wavelength-sweeping light source as the light source so that the wavelength of light projected from the light source changes continuously. The measuring device as described in claim 1, comprising: The logarithmic amplifier uses the increase and decrease of the amount of light received by the event camera as polarity data, and calculates the amount of light received by the event camera based on the accumulation of the polarity data. The measuring device as described in claim 1, further comprising: The adjustment unit is capable of adjusting the amount of data processed by the event camera. The measuring device as claimed in claim 5, wherein The adjustment unit has a region-of-interest function for reading data of a predetermined part of the region. The measuring device as claimed in claim 5, wherein The adjustment unit includes a light cutting unit configured to guide light irradiated on a predetermined part of the area to the event camera, and not guide light irradiated on an area other than the part of the area to the event camera. . The measuring device as claimed in claim 7, wherein The light-cut part includes a liquid crystal panel. The measuring device as claimed in claim 7, wherein The chipping unit is disposed on a common optical path of the measurement light and the reference light. The measuring device as claimed in claim 6, wherein The predetermined partial area is set in advance according to the shape of the object.

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