Shape Measurement System

Abstract

Provided is a shape measurement system with which it is possible to acquire accurate three-dimensional information even when an object subject to measurement has a large concavity / convexity difference on a measurement surface.　The shape measurement system of the present disclosure is provided with a single light source unit, two light-receiving units installed so as to be mutually displaced, and a signal processing unit. The light source unit has a light source, a waveform control lens, and a scan mechanism for scanning, in a specific direction of the measurement object, measurement light that has been transmitted through the waveform control lens. The light-receiving unit has: a light reception lens on which reflected light, which is a part of measurement light from the light source unit that has been reflected by the measurement object, is incident; EVS, which is a non-synchronous imaging device serving as a light reception element; an event issuance unit for detecting an event on the basis of output data from the EVS and outputting event data; and a transmission unit for outputting the event data to the signal processing unit. The signal processing unit has an unnecessary signal removal unit for removing an unnecessary signal caused by incidence of secondary reflection light, and a three-dimensional computation unit for calculating the three-dimensional shape of the measurement object.

Description

[Technical Field]

[0001] The present disclosure relates to a shape measurement system that three-dimensionally measures the shape of a measurement object. [Background technology]

[0002] In contrast to scanning (synchronous) imaging devices that capture images in synchronization with a synchronization signal such as a vertical synchronization signal, there is a non-scanning (asynchronous) imaging device called an EVS (Event-based Vision Sensor) (see, for example, Patent Document 1). Non-scanning imaging devices can detect, as an event, the amount of change in luminance of a pixel that photoelectrically converts incident light exceeding a predetermined threshold.

[0003] One application of non-scanning imaging devices is, for example, a shape measurement device using a light-section method. The light-section method is a technique used to detect shape abnormalities in a measurement target (hereinafter referred to as a "measurement object"), particularly in inspection processes in factories, etc. In shape measurement using this light-section method, a line of light is irradiated onto the measurement object from a light projector, and the width, height, etc. of the measurement object are measured from the imaged cross-sectional shape when the non-scanning imaging device receives the light reflected from the measurement object based on the irradiated light. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-134271 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, one application of a non-scanning imaging device, for example, a shape measurement device using a light-section method, measures the shape by receiving light reflected from an object to be measured based on light irradiated from a light projector. However, in this case, the imaged shape may differ from the actual shape due to ambient light or the reflection of the light irradiated from the light projector, making it impossible to perform accurate shape measurement.

[0006] For example, when capturing reflected light (specular reflected light) that reflects at a measurement point and heads toward the light-receiving unit, there is a possibility that reflected light other than the specular reflected light (secondary reflected light) may also enter the light-receiving unit. In this case, particularly for measurement objects with large unevenness, the optical paths and angles traveled by the secondary reflected light and the specular reflected light may differ greatly, resulting in multiple different detection values ​​being obtained and preventing accurate shape measurement.

[0007] The present disclosure aims to obtain accurate three-dimensional information even when the measurement object has a large unevenness difference on the measurement surface. [Means for solving the problem]

[0008] The present disclosure has been made to achieve the above-mentioned object, and a first aspect thereof is a shape measurement system comprising: a light source unit that emits measurement light to a measurement object; a light receiving unit that receives reflected light of the measurement light reflected from the measurement object; a signal processing unit that has: a three-dimensional shape calculation unit that calculates the three-dimensional shape of the measurement object using event data generated from the reflected light reflected from the measurement object and incident on the light receiving unit; and an unnecessary signal removal unit that removes unnecessary signals generated when unnecessary light other than the reflected light enters the light receiving unit from the outside; and a scanning mechanism that sweeps the measurement light projected from the light source unit onto the measurement object by moving the light source unit or the measurement object, thereby scanning the measurement object.

[0009] In this first aspect, the scanning mechanism is provided in the light source unit, and the light source unit includes a light source and a waveform control lens that controls the waveform of light from the light source, The light receiving unit may include a light receiving lens, an EVS (Event-based Vision Sensor) which is an asynchronous imaging element that captures temporal changes in the reflected light that passes through the light receiving lens and outputs an event signal, an event issuing unit that detects an event based on output data from the EVS and outputs event data, and a transmitting unit that outputs the event data to the signal processing unit.

[0010] In this first aspect, the light source unit is a single light source unit, The light receiving section may include a first light receiving section and a second light receiving section that are positioned offset from each other.

[0011] In addition, in the first aspect of the present disclosure, the light source unit includes a first light source unit and a second light source unit that are installed at positions shifted from each other, the light receiving unit is a single unit, The signal processing unit may include a control signal transmission unit that outputs a control signal to each of the scanning mechanisms at time-divided intervals for each pixel column.

[0012] In addition, in a first aspect of the present disclosure, the light source unit includes a first light source unit including a first light source that emits light of a first wavelength, and a second light source unit that includes a second light source that emits light of a second wavelength, the light receiving unit is a single unit, The EVS is configured by two divided areas, which are divided into a first divided area and a second divided area in units of pixel columns, and The first divided area includes a first filter having a first wavelength transmission characteristic that selectively transmits the reflected light of the first wavelength among the light of the first wavelength and the reflected light of the second wavelength that are reflected by the measurement object, among the measurement light of two different wavelengths emitted from the light source; The second divided area may include a second filter having second wavelength transparency that selectively transmits light of the second wavelength in the reflected light.

[0013] In addition, in the first aspect of the present disclosure, the light source unit includes a first light source unit including the first light source and a second light source unit including a second light source, the first light source unit includes a first optical element that generates a first measurement light having a first polarization plane from light emitted from the first light source; the second light source unit includes a second optical element that generates second measurement light having a second polarization plane from the light emitted from the second light source; the light receiving unit is a single unit, The EVS is divided into two regions, a first divided region and a second divided region, for each pixel column; the first divided region includes a first film that selectively transmits the first reflected light having the first polarization plane and the second reflected light having the second polarization plane, which are reflected by the measurement object and incident on the light receiving unit, respectively, of the two types of measurement light, the first measurement light and the second measurement light; The second division region may include a second film that selectively transmits the second reflected light.

[0014] In this first aspect, the first polarization plane is linearly polarized light vibrating in a vertical direction, The second polarization plane may be linearly polarized light vibrating in the horizontal direction.

[0015] In addition, in the first aspect of the present disclosure, the light source unit is a single unit, and the light source in the light source unit includes a splitting means for splitting light from the light source into at least three wavelength bands, the light receiving unit is a single unit, The EVS is configured by three divided regions, which are divided into first to third divided regions in pixel column units, the first divided region is provided with a first filter having wavelength transmission characteristics that selectively transmits reflected light of a first wavelength band among reflected light of three wavelength bands reflected by the measurement object, among measurement light of three different wavelength bands emitted from the light source; the second divided region is provided with a second filter having wavelength transmission characteristics that selectively transmits reflected light in a second wavelength band among the reflected light in three types of wavelength bands reflected by the measurement object, The third divided region may be provided with a third filter having wavelength transmission characteristics that selectively transmits reflected light in a third wavelength band among the reflected light in three wavelength bands reflected by the object to be measured.

[0016] In this aspect, the splitting means is configured by a prism that splits the white light from the light source into light of three different wavelength bands, The light in the three wavelength bands may be light in the red wavelength band, light in the green wavelength band, and light in the blue wavelength band.

[0017] In addition, in this first aspect, the EVS may compare a signal voltage based on the temporal change in the reflected light with a threshold voltage, and output an event signal by determining whether the signal voltage is smaller or larger than the threshold voltage.

[0018] The shape measurement system disclosed herein is configured to capture multiple independent optical data via multiple optical paths, each with the shortest optical path. Therefore, the data from the specular reflected light (traveling along the shortest optical path) captured from each optical path will have the same value, regardless of the optical path taken, as long as the specular reflected light is reflected at the same reflection point. That is, the physical shape (e.g., height) at the same point on the measured object is uniquely determined (there is only one shape at the same position). Therefore, the height value at the same point will not differ, regardless of the shortest optical path (route) taken by the reflected light, as long as it is specular reflected light. Therefore, by finding pairs of identical data values ​​that should necessarily exist, it is possible to reliably and accurately determine which data is the true data regarding the measured surface, since the data is obtained from specular reflected light. That is, even if unwanted secondary reflected light from the reflected light reflected and scattered by the measured surface of the measured object enters the light receiving unit, erroneous distance measurements due to data related to this secondary reflected light can be prevented. Furthermore, according to the shape measurement system of the present disclosure, the light receiving element uses an EVS (Event-based Vision Sensor), which is an asynchronous imaging device, as will be described in detail later, thereby enabling high-speed and accurate shape measurement. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic diagram showing an outline of the configuration of a shape measurement system according to a first embodiment of the present disclosure. [Figure 2] 1 is a schematic configuration diagram showing a shape measurement system according to a first embodiment of the present disclosure. [Figure 3] FIG. 10 is a configuration block diagram showing an imaging device showing a first configuration example according to a second embodiment of the present disclosure. [Figure 4] 4 is an output diagram showing the temporal processing operation of output signals in each pixel column (pixel array) in the light receiving section of the first configuration example of the present disclosure. FIG. [Figure 5] 1 is a block diagram showing an example of the configuration of an imaging unit of an imaging device according to a first configuration example of the present disclosure. [Figure 6]2 is a block diagram showing an example of the configuration of a pixel array section in an imaging section according to a first configuration example of the present disclosure. FIG. [Figure 7] 1 is a circuit diagram showing an example of a circuit configuration of a pixel according to a first configuration example of the present disclosure. [Figure 8] 3 is a block diagram showing an example of the configuration of an address event detection unit according to a first configuration example of the present disclosure. FIG. [Figure 9] FIG. 2 is a principle diagram showing optical paths of incident light and reflected light on a measurement object according to a first configuration example of the present disclosure. [Figure 10] 1A is an explanatory diagram showing the scanning direction of slit light on a measurement object according to a first configuration example of the present disclosure, and FIG. 1B is an explanatory diagram showing the detection principle of a measurement value related to the height of the measurement object. [Figure 11] 1 is an explanatory diagram for deriving an arithmetic expression for calculating the height of a measurement object according to a first configuration example of the present disclosure. FIG. [Figure 12] FIG. 10 is a conceptual diagram showing a generation distribution of reflected light events according to a first configuration example of the present disclosure. [Figure 13] FIG. 10 is a configuration block diagram showing a shape measurement system according to a second configuration example of the present disclosure. [Figure 14] 10 is a timing chart showing the operations of a light source unit and a light receiving unit of a shape measurement system according to a second configuration example of the present disclosure. [Figure 15] FIG. 10 is a configuration block diagram showing a shape measurement system according to a third configuration example of the present disclosure. [Figure 16] FIG. 10 is a configuration block diagram showing each pixel column of an EVS of a shape measurement system according to a third configuration example of the present disclosure. [Figure 17] FIG. 10 is a configuration block diagram showing a shape measurement system according to a fourth configuration example of the present disclosure. [Figure 18] 10A and 10B are optical path diagrams illustrating the functions of a first polarizer and a second polarizer of a shape measurement system according to a fourth configuration example of the present disclosure. [Figure 19] FIG. 10 is a configuration diagram showing a pixel array of an EVS of a shape measurement system according to a fourth configuration example of the present disclosure. [Figure 20] FIG. 10 is a block diagram showing a configuration of a shape measurement system according to a fifth configuration example of the present disclosure. [Figure 21] 10 is an explanatory diagram showing the projection state of each slit light, which is incident light and is divided into three wavelengths for RGB, in a light source unit of a shape measurement system according to a fifth configuration example of the present disclosure. FIG. [Figure 22] 10 is an explanatory diagram showing the incidence state of R, G and B, in which the wavelengths of reflected light are divided into three, in a light receiving unit of a shape measurement system according to a fifth configuration example of the present disclosure. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, modes for carrying out the technology of the present disclosure (hereinafter referred to as "embodiments") will be described in detail with reference to the drawings. The technology of the present disclosure is not limited to each embodiment, and various numerical values ​​and materials in each embodiment are examples. In the following description, the same reference numerals will be used for the same elements or elements having the same functions, and duplicated descriptions will be omitted. The description will be given in the following order. 1. Shape measurement system according to the first embodiment of the present disclosure 2. Shape measurement system according to the second embodiment of the present disclosure 2-1. First configuration example: Single light source + multiple light receiving units 2-2. Second configuration example: Multiple light sources + single light receiving unit (light source time-division control) 2-3. Third configuration example: Multiple light sources + single light receiving unit (wavelength division control) 2-4. Fourth Configuration Example: Multiple Light Sources + Single Light Receiver (Polarization Switching Control) 2-5. Fifth configuration example: Single light source + single light receiving unit (split by prism) 3. Configurations that the present disclosure can take

[0021] <1. Shape measurement system according to the first embodiment> FIG. 1 is a schematic diagram showing a shape measurement system according to a first embodiment of the present disclosure, and FIG. 2 is a block diagram showing the general configuration of the shape measurement system according to the present disclosure. In FIG. 1 and subsequent figures, in order to clarify the depth direction, scanning and movement direction, and height direction of the object to be measured, respectively, a mutually orthogonal three-dimensional Cartesian coordinate system is set as the X direction, Y direction, and Z direction. Note that this disclosure employs a left-handed system, and the origin is particularly specified as one of the four corners of the object.

[0022] [Configuration of shape measurement system] The shape measurement system 1 of the present disclosure generally comprises a stage 2, a shape measurement device 10 that performs three-dimensional measurement of a measurement surface 100A of a measurement object 100 that is mounted in a stationary state on the stage 2, a movement mechanism 3 that constitutes a scanning mechanism that intermittently moves the shape measurement device 10 in the Y direction, a control unit 4 that controls the movement mechanism 3, and a signal processing unit (hereinafter referred to as a "signal processing unit") 13 that processes signals in the shape measurement device 10. As shown in FIG. 2 , the shape measurement device 10 of this embodiment comprises a light source unit 11 and a light receiving unit 12, which are housed inside a head H.

[0023] The shape measurement system 1 of the present disclosure uses a non-scanning (hereinafter referred to as "asynchronous") imaging method called an EVS (Event-based Vision Sensor). This will be described in detail later. In this embodiment, shape measurement operations are performed sequentially and continuously on multiple measurement objects 100 shown in FIG. 1, starting from the left side and moving to the right side. For this purpose, a moving mechanism 3 is provided, but of course, the moving mechanism 3 is not necessary when performing shape measurement on only a single measurement object 100.

[0024] The stage 2 of this embodiment is a rectangular flat plate of uniform thickness in plan view, with its two vertical and horizontal sides aligned so as to coincide with the X and Y directions, respectively. The stage 2 of this embodiment is placed on a base or the like (not shown).

[0025] As shown in FIGS. 1 and 2 , the movement mechanism 3 intermittently moves the head H housing the shape measuring device 10 in the Y direction at high speed in accordance with the measurement of the object 100 under the control of a movement control unit 42 (described later). This sequentially measures each object 100. The movement mechanism 3 for this purpose may be, for example, a robot. It may also be a rack and pinion, a ball screw, an endless belt, a wire, or any other suitable means. While the movement mechanism 3 of this embodiment is configured to intermittently move the head H in the Y direction, the present disclosure is not limited to this. That is, instead of the head H, either the stage 2 or the base may move. The movement mechanism of the present disclosure may, for example, move the light source unit inside the head H, as in the second embodiment, or may move only the light source inside the light source unit.

[0026] The control unit 4 includes a system control unit 41 and a movement control unit 42. The system control unit 41 controls the movement control unit 42 and the profile measuring device 10 at a predetermined timing. The movement control unit 42 controls the movement mechanism 3 that intermittently moves the profile measuring device 10. The control unit 4 can move the head H at high speed in the Y direction from the start point to the end point of the measurement object 100.

[0027] The signal processing unit 13 acquires the three-dimensional shape of the object 100 by performing predetermined signal processing at high speed based on the "event data" obtained by the light receiving unit 12 of the shape measuring device 10. As shown in FIG. 2, the signal processing unit 13 of this embodiment includes a control signal transmitting unit 131, an unnecessary signal removing unit 132, a three-dimensional shape calculating unit (hereinafter referred to as the "3D calculating unit") 133, and a memory 134. Details of each of the above elements, including the "event data", will be described later.

[0028] Although the object to be measured 100 is not particularly limited, in the first embodiment of the present disclosure, for example, the object has a rectangular bottom surface and an irregularly uneven top surface, which is the measurement surface. Even when the unevenness difference is large, the shape measuring device 10 of the present disclosure can detect and measure the shape at high speed by using the EVS described above, and with high accuracy by using the calculation formula described below.

[0029] [Actions and Effects of the First Embodiment] The shape measuring device 10 according to the shape measuring system 1 of the present disclosure performs three-dimensional shape measurements of the length (Y), depth (X), and height (Z) of the object 100. As a shape measuring means according to the present disclosure, a slit light (hereinafter sometimes referred to as "measurement light") that is generated by a light source unit 11 in the head H and has a wide band shape or a tapered fan shape is used. Note that the shape of this slit light is not limited to the above. For example, it may have a specific shape that corresponds to the shape of the object or surface being measured and is effective for shape measurement.

[0030] The shape measuring device 10 sequentially projects slit light in the direction of a vertical cross section (XZ plane) of the object 100, thereby measuring the shape in units of one pixel column. Simultaneously with the projecting operation of the slit light in the XZ direction, the scanning mechanism 113 in the light source unit 11 shown in FIG. 3 is activated to perform a scanning operation from left to right in the Y (horizontal) direction. That is, a series of sweeping operations is performed from the start to the end in the Y (horizontal) direction. In this way, the slit light is projected and swept in the Y direction, thereby performing three-dimensional shape measurement.

[0031] In the shape measurement system 1 according to the present disclosure, measurement light on the light projection (or outward path) side traveling from a light source in a light source unit (not shown) toward the measurement object 100 can be scattered and reflected at the same measurement point (measurement position) on the measurement object 100, and then, on the reflection (or return path) side traveling toward a light receiving unit (not shown), at least two types of reflected light (these are regular reflected lights, which will be described later) can be used, which follow different shortest optical paths. Note that a specific shape measurement method using this reflected light will be described in detail in a second embodiment (to be described later) along with its qualitative principles.

[0032] The above is the shape measurement operation for each measurement object 100 by projecting laser light from the shape measurement device 10. In this embodiment, this series of shape measurement operations is performed sequentially for each measurement object 100. For this reason, the movement control unit 42 controls the intermittent operation of the movement mechanism 3 at regular time intervals. As a result, when the measurement operation for one measurement object is completed, the head H of the shape measurement device 10 is moved one step in the Y direction to the next measurement object. By repeating this intermittent operation for the head H each time, the three-dimensional (hereinafter referred to as "3D") shape of the measurement surface 100A of each measurement object 100 can be continuously acquired by the EVS.

[0033] As described above, in this embodiment, an asynchronous imaging device called an EVS is used. By using this EVS, it is possible to obtain the effect of performing shape measurement at high speed in terms of time, unlike conventional sensors.

[0034] <2. Shape measuring device according to the shape measuring system of the second embodiment> (2-1. First configuration example) Next, a shape measuring device provided in a shape measuring system according to a second embodiment of the present disclosure will be described in detail with reference to the drawings. Fig. 3 shows a first aspect of the second embodiment according to the present disclosure (hereinafter referred to as "first configuration example"). That is, Fig. 3 shows the configuration of a shape measuring device 10A according to the first configuration example, in particular, the configuration of a light source unit 11, a light receiving unit 12, and a signal processing unit 13 provided in this shape measuring device 10A. Note that the same parts as those in Figs. 1 and 2 are assigned the same reference numerals to avoid redundant explanation.

[0035] The form measuring device 10A of the present disclosure may have the same configuration as that used in the form measuring system 1 of the first embodiment, or may have a different configuration. The form measuring device 10A of this first configuration example is configured to include a single light source unit 11 and multiple light receiving units 12.

[0036] As described above, the form measuring device 10A of this configuration example houses the single light source unit 11, the two light receiving units 12 consisting of the first light receiving unit 12A and the second light receiving unit 12B, and the signal processing unit 13 in the head H. Note that the head H of the present disclosure may be configured to house only the light source unit 11 and the light receiving unit 12, with the signal processing unit 13 installed separately, and to exchange data using wireless communication, infrared communication, or the like.

[0037] It is preferable to separate the two light receiving units 12, the first light receiving unit 12A and the second light receiving unit 12B, as far apart as possible. For example, the shape measuring device 10A of this first configuration example can be installed at opposite positions in the lateral (Y) direction with the light source unit 11 at the center, but they do not have to be arranged symmetrically with the light source unit 11 at the center.

[0038] [Configuration of shape measurement device] As described above, the light source section 11 of this configuration example (hereinafter referred to as "light source section 11A") is configured as a single element, and specifically includes a light source 111A, a waveform control lens 112, and a scanning mechanism 113, as shown in Fig. 3. In the following description of this configuration example, for the sake of simplicity, the "A" will be omitted from the elements of the light source section 11A, particularly from the light source 111A.

[0039] A semiconductor laser (hereinafter referred to as "semiconductor laser 111") can be used as the light source 111. The semiconductor laser 111 of this embodiment can continuously oscillate laser light of, for example, a blue wavelength (λb). The shape measurement means for the measurement object 100 of the first configuration example uses this blue light as measurement light. Note that the laser light used in the light source unit of the present disclosure is not limited to this blue light. The light source of this configuration example preferably emits high-intensity light and has a certain degree of directionality. Furthermore, the illumination light used does not need to be coherent like laser light, but preferably has little chromatic aberration or other aberrations. Note that when a laser is used as the light source, it may be an edge-emitting laser (EEL) or a vertical-cavity surface-emitting laser (VCSL).

[0040] The waveform control lens 112 includes a waveform shaping lens. Z This waveform shaping lens is an optical element for shaping the emitted laser light into a slit-shaped waveform. In the waveform shaping lens of this configuration example, a cylindrical lens (hereinafter referred to as "cylindrical lens 112") is used. Specifically, the waveform shape of blue laser light oscillated and emitted from the semiconductor laser 111 in the form of a beam, for example, is shaped into a thin, wide rectangular (band-shaped) light in the traveling direction, or a thin, fan-shaped light in the traveling direction. light( Hereafter, these will be referred to as "line slit light" or simply "slit light.") to In this example configuration, the line slit light as shown in FIG. 1 is irradiated simultaneously over the entire row of pixels (columns) having a narrow vertical length along the depth (X) direction of the measurement object 100.

[0041] The scanning mechanism 113 performs sweep scanning by sending out laser light, whose waveform has been formed into a slit shape by the cylindrical lens 112, in the Y (row) direction over time. In this way, the scanning mechanism 113 can measure the shape of the entire measurement surface 100A of the measurement object 100 in three dimensions by sequentially sending out laser light in the Y direction.

[0042] In the configuration example of the present disclosure, the shape measurement device 10A scans the stationary object 100 to measure the three-dimensional shape of the object 100. In the present disclosure, the shape measurement device 10A may be placed stationary, while the object 100 is moved and scanned by an appropriate transport means to perform measurement. However, in the latter type, due to the characteristics of the image capture device 122 described below, when a moving object appears, it captures the object and outputs a signal. Therefore, it is necessary to take care, for example, to measure the shape in a completely dark environment by turning off the illumination light, to use an infrared region for the laser light source wavelength, and to further attach an optical filter in the same wavelength band in front of the image capture element of the image capture device 122.

[0043] 3, the light receiving unit 12 of this configuration example includes a light receiving lens 121, an imaging device 122, an event issuing unit 123, and a transmitting unit 124. In addition, in this first configuration example, for ease of understanding, the light receiving unit 12 will be described with the front part as a "light receiving function unit" and the rear part as a "detection function unit." In this configuration example of the present disclosure, the first light receiving unit 12A specifically includes a first light receiving lens 121A, a first image capturing device 122A, a first event publishing unit 123A, and a first transmitting unit 124A. On the other hand, the second light receiving unit 12B specifically includes a second light receiving lens 121B, a second image capturing device 122B, a second event publishing unit 123B, and a second transmitting unit 124B. In the following configuration example, for ease of explanation, the symbols added to the names of the above components will be represented by only three digits, and the "A" and "B" will be omitted.

[0044] The light receiving function unit, which is the front-stage part, receives reflected light (scattered light) from the measurement surface 100A of line slit light projected from the light source unit 11A. The light receiving function unit of this embodiment can be equipped with a light receiving lens 121 and an imaging unit 21 (described later) that includes optical elements including an imaging device 122 and various circuits. As a result, the light receiving function unit acquires brightness (changes) data related to the shape of the measurement object 100 by measuring the measurement object 100 in pixel row units. From this, information signals such as the outer shape and position information linked thereto, i.e., signals for detecting event data (described later), are output to the detection function unit (located in the rear stage). The imaging unit 21 will be described in detail later.

[0045] Of the light receiving function units, the light receiving lens 121 forms an image of the incident line slit light on the imaging device 122. The light receiving lens of the present disclosure simply forms an image of the reflected light on the imaging device 122.

[0046] The imaging device 122 uses the aforementioned EVS (Event-based Vision Sensor) as a sensor of a different type from conventional sensors. This EVS is composed of an asynchronous imaging device, and pixels that photoelectrically convert incident light reflected by the object 100 are arranged two-dimensionally in a matrix. This EVS has multiple pixel circuits arranged in a two-dimensional lattice. A group of pixel circuits arranged in the depth (X) direction is called a "row," and a group of pixel circuits arranged in the horizontal (Y) direction perpendicular to the row is called a "column." Each EVS captures a photoelectric conversion signal into each pixel based on the reflected light β1 and β2 received in accordance with image information for each pixel column. The input data is output to the event issuing unit 123.

[0047] Meanwhile, the detection function unit performs signal processing, thereby capturing signals from incident light as events. The EVS outputs only pixel information where a change in luminance has occurred for each pixel, pixel by pixel, allowing for stable signal output without being affected by the color or reflectance of the object being measured or ambient light. The detection function unit can include an event issuing unit 123 and a transmitting unit 124.

[0048] The event issuing unit 123 constitutes a part of the detection function unit. The event issuing unit 123 receives a synchronization signal from the control signal transmitting unit 131, and outputs an event signal (described later) for 3D reconstruction related to the surface shape of the measuring object 100 obtained from the EVS 122 in synchronization with the synchronization signal to the transmitting unit 124.

[0049] That is, when the event publishing unit 123 of this embodiment detects an event, it detects the position of the event from the synchronization signal input at that time t. This position detection will be described later with reference to FIGS. 5 to 8. The event publishing unit 123 also detects a change in luminance for each pixel address receiving light in real time as an "address event." When the event publishing unit 123 detects an address event, it compares the luminance with that of the immediately preceding address event. As a result, it detects and captures an event in which a preset luminance change amount exceeds a predetermined threshold value as an "event," and outputs data (called "event data") including position information (coordinate data) indicating the coordinate position of the event to the transmitting unit 124. In addition to the position information, the event data can also include time information indicating the relative time when the event occurred. The event data may also include gradation information indicating the signal level.

[0050] The transmitting unit 124 outputs the event data for three-dimensional reconstruction output from the event issuing unit 123 to an unnecessary signal removing unit 132 (described later) on the signal processing unit 13 side.

[0051] [Configuration of signal processing unit] The signal processing unit 13 of this embodiment detects and stores three-dimensional data of the object 100 at high speed based on the data obtained from the light receiving unit 12. As described above, the signal processing unit 13 includes the control signal transmitting unit 131, the unwanted signal removing unit 132, the 3D calculation unit 133, the memory 134, etc.

[0052] As shown in FIG. 4 , the control signal transmitter 131 outputs a control signal to the light source 111 and the scanning mechanism 113 to start the shape measurement operation of the object 100 (at time t0). That is, the control signal transmitter 131 also starts a sweep scanning operation of the object 100 in the lateral (Y) direction in synchronization with the laser oscillation operation at the start of shape measurement. The control signal transmitter 131 also outputs a synchronization signal to the event publisher 123 of each light receiving unit 12A, 12B to drive the event publisher 123 in synchronization with the laser oscillation operation of the light source 111 and the sweep operation of the scanning mechanism 113. As a result, the event publisher 123 can link the synchronization signal to event data at the same time as inputting a luminance signal via the EVS 122. This generates shape measurement data for all pixels across the entire surface of the object 100.

[0053] In a system in which multiple objects are arranged, as shown in FIG. 1 , the intermittent operation of the moving mechanism 3, which moves the shape measuring device 10A in the Y direction, allows for the shape measurements of multiple objects to be performed one after another (this will be referred to as “multiple object measurement”). On the other hand, in a system for measuring the shape of a single object without a moving mechanism, the same control as for the sweep scanning operation of one course can be performed to repeatedly and continuously perform multiple shape measurements of a single object over time (this will be referred to as “single object measurement”). As a result, single object measurement allows for the detection of changes over time in the object 100 at very short time intervals. Incidentally, the first and subsequent configuration examples employ the “single object measurement” type, which is convenient for situations in which the shape changes over time. In the present disclosure, the “multiple object measurement” may be employed for the first and subsequent configuration examples.

[0054] The unnecessary signal removal unit 132 removes unnecessary signals related to multipath reflected light (sometimes referred to as "secondary reflected light"), which can lead to measurement errors when laser light from the light source 111 is incident on the measurement surface 100A. Multipath reflected light is light that enters from paths not intended for measurement, and is mainly caused by multiple reflections from various objects in the external world. In this configuration example, the unnecessary signal removal unit 132 removes unnecessary signals generated by secondary reflected light that is incident at an angle of incidence different from the angle of incidence (reference angle) of particularly necessary scattered light (this will be referred to as "regular reflected light" described later) from the slit light from the light source unit 11A that enters the imaging device 122.

[0055] Specifically, the coordinates (X, Y, Z) of each pixel corresponding to a specified point on the surface of the measurement object 100, i.e., the point of incidence of the slit light at a certain time t, are uniquely determined. That is, in the light receiving unit 12, the angle of incidence of the reflected light from the light source 111 toward the measurement object 100 is a fixed, specific value (normal incident angle). The angle of incidence of the reflected light (sometimes referred to as "normal incident light") when incident at this normal incident angle on the measurement object 100 and reflected by the measurement object 100 and entering the imaging device 122 (sometimes referred to as "specular reflected light") is the same as that of the previous point if the height is the same. Therefore, when the incident angle of the specular reflected light on the light receiving unit 12 is different, there is a difference in the unevenness of the measurement surface compared to the previous point, resulting in a different height. That is, it can be seen that the height of the measurement object 100 has changed.

[0056] The secondary reflected light may erroneously enter the light receiving unit 12 at an angle of incidence different from the normal angle of incidence, which may result in erroneous detection of the shape at that point. Therefore, the unnecessary signal removal unit 132 removes electrical signals (hereinafter referred to as "unnecessary signals") other than the electrical signals that should be generated from the intensity or amount of received light when the light is incident at the original normal angle of incidence (hereinafter referred to as "normal electrical signals"). In other words, electrical signals other than the normal electrical signals that are different from the unique photocurrent value or photoelectromotive force value (hereinafter referred to as "unnecessary signals").

[0057] 3D calculation unit 133 uses the normal electrical signal obtained after unnecessary signals that generate unnecessary noise have been removed by unnecessary signal removal unit 132 to generate, using an arithmetic formula described later, a two-dimensional shape (referred to as "two-dimensional data") obtained for each pixel row by cutting object 100 into lines with each slit light. Then, scanning mechanism 113 sweeps the slit light in the Y direction, connecting each line of two-dimensional data to generate a three-dimensional shape of object 100 (hereinafter referred to as "3D shape").

[0058] The memory 134 stores and preserves shape information relating to the three-dimensional shape of the measurement surface 100A of the measurement object 100, which is event data for each pixel of the measurement object 100, obtained by processing the data, particularly height information (or thickness information), sequentially acquired by the shape measurement device 10A, using required circuits.

[0059] [Image capture unit configuration example] Next, the imaging section 21 including the imaging device 122 of the present disclosure will be described with reference to FIGS. An example of the configuration of the imaging section 21 including the imaging device 122 of the light receiving section 12 according to the first example configuration will be specifically described below. FIG. 5 is a block diagram showing an example of the configuration of the imaging section 21.

[0060] As shown in Figure 5, the imaging unit 21 in this configuration example uses an asynchronous imaging device called EVS, and includes a pixel array unit 211, a drive unit 212, an arbiter unit 213, a column processing unit 214, and a signal processing unit 215.

[0061] 1) Pixel array section In the imaging unit 21 having the above configuration, a plurality of pixels 210 are two-dimensionally arranged in a matrix (array) in the pixel array unit 211. Vertical signal lines VSL, which will be described later, are wired for each pixel column in this matrix-like pixel arrangement.

[0062] Each of the plurality of pixels 210 generates a pixel signal, which is an analog signal of a voltage corresponding to the photocurrent. Each of the plurality of pixels 210 also detects the presence or absence of an address event based on whether or not the amount of change in the photocurrent exceeds a predetermined threshold. When an address event occurs, the pixel 210 outputs a request to the arbiter unit 213.

[0063] 2) The drive part The driving section 212 drives each of the plurality of pixels 210 to output a pixel signal generated in each pixel 210 to the column processing section 214 .

[0064] 3) Arbiter section The arbiter unit 213 arbitrates requests from each of the multiple pixels 210 and transmits a response based on the arbitration result to the pixel 210. Upon receiving the response from the arbiter unit 213, the pixel 210 supplies event data indicating the detection result (address event detection signal) to the drive unit 212 and the signal processing unit 215. The event data can also be read from multiple rows from the pixel 210.

[0065] 4) Column processing section The column processing unit 214 is composed of, for example, an analog-to-digital converter and performs processing such as converting analog pixel signals output from the pixels 210 in each pixel column of the pixel array unit 211 into digital signals. Then, the column processing unit 214 supplies the digital signals after analog-to-digital conversion to the signal processing unit 215.

[0066] 5) The signal processing section The signal processing unit 215 performs predetermined signal processing such as CDS (Correlated Double Sampling) processing and image recognition processing on the digital signal supplied from the column processing unit 214. Then, the signal processing unit 215 outputs data indicating the processing result and the event data supplied from the arbiter unit 213 via a signal line 216.

[0067] [Pixel array configuration example] FIG. 6 is a block diagram showing an example of the configuration of the pixel array unit 211. As shown in FIG.

[0068] In the pixel array section 211, which is made up of a plurality of pixels 210 arranged two-dimensionally in a matrix, each of the plurality of pixels 210 has a photoelectric conversion section 51, a pixel signal generation section 52, and an address event detection section 53.

[0069] 1) Photoelectric conversion unit In the pixel 210 having the above configuration, the photoelectric conversion unit 51 performs photoelectric conversion on incident light to generate a photocurrent. Then, the photoelectric conversion unit 51 supplies the photocurrent generated by photoelectric conversion to either the pixel signal generation unit 52 or the address event detection unit 53 under the control of the drive unit 212 (see FIG. 5 ).

[0070] 2) Pixel signal generation unit The pixel signal generation unit 52 generates a pixel signal SIG, which is a voltage signal corresponding to the photocurrent supplied from the photoelectric conversion unit 51, and supplies this generated pixel signal SIG to the column processing unit 214 (see Figure 5) via the vertical signal line VSL.

[0071] 3) Address event detection section The address event detection unit 53 detects whether an address event (hereinafter sometimes simply referred to as "event") has occurred based on whether the amount of change in photocurrent from each of the photoelectric conversion units 51 has exceeded a predetermined threshold. An address event consists of, for example, an ON event indicating that the amount of change in photocurrent has exceeded an upper threshold, and an OFF event indicating that the amount of change has fallen below a lower threshold. The address event detection signal consists of, for example, one bit indicating the detection result of an ON event and one bit indicating the detection result of an OFF event. The address event detection unit 53 can also be configured to detect only ON events.

[0072] When an address event occurs, the address event detection unit 53 supplies a request to the arbiter unit 213 (see FIG. 5) requesting transmission of an address event detection signal. Then, upon receiving a response to the request from the arbiter unit 213, the address event detection unit 53 supplies an address event detection signal (event data) to the drive unit 212 and the signal processing unit 215.

[0073] [Pixel circuit configuration example] 7 is a circuit diagram showing an example of the circuit configuration of the pixel 210. As described above, each of the plurality of pixels 210 includes a photoelectric conversion unit 51, a pixel signal generation unit 52, and an address event detection unit 53.

[0074] 1) Photoelectric conversion unit In the pixel 210 configured as described above, the photoelectric conversion unit 51 includes a photoelectric conversion element (light receiving element) 511, a transfer transistor 512, and an OFG (Over Flow Gate) transistor 513. For example, an N-type MOS (Metal Oxide Semiconductor) transistor can be used as the transfer transistor 512 and the OFG transistor 513. The transfer transistor 512 and the OFG transistor 513 are connected in series to each other.

[0075] 1-1) Photoelectric converter The photoelectric conversion element 511 is connected between a common connection node N1 of the transfer transistor 512 and the OFG transistor 513 and the ground, and performs photoelectric conversion on incident light to generate charges of an amount corresponding to the amount of incident light.

[0076] 1-2) Transfer transistor 5 supplies a transfer signal TRG to the gate electrode of the transfer transistor 512. In response to the transfer signal TRG, the transfer transistor 512 supplies the charge photoelectrically converted by the photoelectric conversion element 511 to the pixel signal generation unit 52.

[0077] 1-3) OFG transistor A control signal OFG is supplied to the gate electrode of the OFG transistor 513 from the driving unit 212. In response to the control signal OFG, the OFG transistor 513 supplies the electrical signal generated by the photoelectric conversion element 511 to the address event detection unit 53. The electrical signal supplied to the address event detection unit 53 is a photocurrent made up of electric charges.

[0078] 2) Pixel signal generation unit The pixel signal generation unit 52 includes a reset transistor 521, an amplification transistor 522, a selection transistor 523, and a floating diffusion layer 524. The reset transistor 521, the amplification transistor 522, and the selection transistor 523 may be, for example, an N-type MOS transistor.

[0079] The pixel signal generation unit 52 receives charges photoelectrically converted by the photoelectric conversion element 511 from the photoelectric conversion unit 51 via the transfer transistor 512. The charges supplied from the photoelectric conversion unit 51 are accumulated in the floating diffusion layer 524. The floating diffusion layer 524 generates a voltage signal having a voltage value corresponding to the amount of accumulated charge. In other words, the floating diffusion layer 524 converts the charges into a voltage.

[0080] 2-1) Reset transistor The reset transistor 521 is connected to the power supply voltage V DD The reset transistor 521 is connected between the power supply line and the floating diffusion layer 524. A reset signal RST is supplied to the gate electrode of the reset transistor 521 from the driving unit 212. The reset transistor 521 initializes (resets) the amount of charge in the floating diffusion layer 524 in response to the reset signal RST.

[0081] 2-2) Amplification transistor The amplifier transistor 522 is connected to the power supply voltage V DD The amplifier transistor 522 is connected in series with the selection transistor 523 between the power supply line and the vertical signal line VSL. The amplifier transistor 522 amplifies the voltage signal converted from charge to voltage by the floating diffusion layer 524.

[0082] 2-3) Select transistor A selection signal SEL is supplied to the gate electrode of the selection transistor 523 from the drive unit 212. In response to the selection signal SEL, the selection transistor 523 outputs the voltage signal amplified by the amplification transistor 522 as a pixel signal SIG to the column processing unit 214 (see FIG. 5) via the vertical signal line VSL.

[0083] In the imaging unit 21 having a pixel array section 211 in which pixels 210 of the above configuration are arranged two-dimensionally, when the driving section 212 is instructed to start detecting an address event by a light receiving control section not shown, the driving section 212 drives the OFG transistor 513 of the photoelectric conversion section 51 by supplying a control signal OFG to the OFG transistor 513, thereby causing the OFG transistor 513 to supply a photocurrent to the address event detection section 53.

[0084] 2-4) Floating diffusion layer When the occurrence of an event is detected in a certain pixel 210, the drive unit 212 turns off the OFG transistor 513 of that pixel 210 to stop the supply of photocurrent to the address event detection unit 53. Next, the drive unit 212 drives the transfer transistor 512 by supplying a transfer signal TRG to the transfer transistor 512, causing the charge photoelectrically converted by the photoelectric conversion element 511 to be transferred to the floating diffusion layer 524.

[0085] In this way, the imaging unit 21 having the pixel array unit 211 formed by two-dimensionally arranging the pixels 210 configured as described above outputs only the pixel signal of the pixel 210 in which the occurrence of an event is detected to the column processing unit 214. This makes it possible to reduce the power consumption of the imaging unit 21, and in turn the image processing amount of the imaging device 122, as well as the amount of image processing, compared to when pixel signals of all pixels are output regardless of whether an event has occurred.

[0086] Note that the configuration of the pixel 210 illustrated here is merely an example, and is not limited to this configuration example. For example, a pixel configuration not including the pixel signal generation unit 52 is also possible. In this pixel configuration, the OFG transistor 513 is omitted from the photoelectric conversion unit 51, and the function of the OFG transistor 513 is given to the transfer transistor 512.

[0087] 3) Address event detection section 8 is a block diagram showing an example of the configuration of the address event detection unit 53. As shown in the figure, the address event detection unit 53 according to this example configuration includes a current-voltage conversion unit 531, a buffer 532, a subtractor 533, a quantizer 534, and a transfer unit 535.

[0088] 3-1) Current-to-voltage converter and buffer The current-voltage converter 531 converts the photocurrent from the photoelectric converter 51 of the pixel 210 into a logarithmic voltage signal. The current-voltage converter 531 supplies the converted voltage signal to a buffer 532. The buffer 532 buffers the voltage signal supplied from the current-voltage converter 531 and supplies it to a subtractor 533.

[0089] 3-2) Subtractor and quantizer The subtractor 533 receives a row drive signal from the driver 212. The subtractor 533 reduces the level of the voltage signal supplied from the buffer 532 in accordance with the row drive signal. The subtractor 533 then supplies the voltage signal after the reduction in level to the quantizer 534. The quantizer 534 quantizes the voltage signal supplied from the subtractor 533 into a digital signal and outputs it to the transfer unit 535 as an address event detection signal (event data).

[0090] 3-3) Transfer section The transfer unit 535 transfers the address event detection signal (event data) supplied from the quantizer 534 to the arbiter unit 213 etc. When the occurrence of an event is detected, the transfer unit 535 supplies a request to the arbiter unit 213 to request transmission of the address event detection signal. Then, when the transfer unit 535 receives a response to the request from the arbiter unit 213, it supplies the address event detection signal to the drive unit 212 and the signal processing unit 215.

[0091] [Method for measuring the shape of the object (measurement principle)] Next, the principle of shape measurement by the shape measuring device 10A of the first configuration example, which is related to the shape measuring system of the second embodiment of the present disclosure, will be described with reference to FIGS. In the first configuration example of the present disclosure, as described above, the three-dimensional shape of the measurement object 100 (measurement surface 100A) is detected using a single light source unit 11A and two light receiving units 12 (i.e., light receiving units 12A and 12B).

[0092] The positional relationship of the light source unit 11A and the light receiving unit 12, which is made up of the light receiving units 12A and 12B, is not particularly limited, but in this configuration example, the light receiving units 12A and 12B are arranged on both sides of the light source unit 11A, as shown in Fig. 9. These light receiving units 12A and 12B do not need to be arranged symmetrically with respect to the light source unit 11A, and it is preferable that they are spaced as far apart as possible from each other. Furthermore, the light source unit 11A and the light receiving unit 12 may or may not be arranged along the same YZ plane.

[0093] The blue light from the semiconductor laser (LD) which is the light source 111 of the light source unit 11A is waveform-processed by the cylindrical lens 112 shown in Figure 3, and becomes line slit light parallel to the XZ plane, which is projected and irradiated onto the measurement surface 100A of the measurement object 100.

[0094] On measurement surface 100A, this line slit light is scattered according to the unevenness of measurement surface 100A, and the scattered light passes through the light receiving lenses of light receiving units 12A and 12B and enters EVS1 and EVS2, which are imaging devices 122A and 122B.

[0095] There is a risk that scattered light generated by scattering at the measurement surface 100A may be incident on the EVS1 and EVS2, which are the imaging devices 122A and 122B, as reflected light. Therefore, in the present disclosure, among the reflected light that is scattered and reflected at each position on the measurement surface 100A and then travels toward the light receiving units 12A and 12B, two measurement light beams that travel along different shortest optical paths toward the light receiving units 12A and 12B, which are arranged at different positions, are considered to be specularly reflected light. Data from these specularly reflected light beams is used for shape measurement in the present disclosure.

[0096] Even in the object 100 of this configuration example, secondary waves (secondary reflected light) may be incident on the EVS1 and EVS2 (hereinafter sometimes referred to as "EVS1 and 2"), which are the imaging devices 122, potentially resulting in measurement (distance measurement) errors. Therefore, the distance to the measurement surface 100A at each EVS1 and 2 is calculated using a predetermined arithmetic formula (described later) from the data obtained by measurement at each EVS1 and 2 at each time t. The data obtained by both EVS1 and 2 that match are used as data from specular reflected light. The cross-sectional shape of the object 100 can be calculated from this specular reflected light using the following arithmetic formula, and the cross-sectional shape can be captured as a three-dimensional shape. This will be described in detail with reference to FIGS. 10 and 11.

[0097] The calculation formulas used here are as follows, and these formulas can be used to calculate the shape of the measurement surface 100A at each point (X, Y, Z). X = X coordinate of a point in the depth direction (1) Y = (scanning speed of the scanning mechanism) (operating time of the scanning mechanism) - (distance measurement error in the Y direction Δy) (2) Z=(Distance measurement error Δy in Y direction) / (tanθ) (3) Here, θ is the angle of inclination of the light source relative to the normal.

[0098] Here, the derivation of equation (3) will be explained with reference to the drawings. 11 shows the optical path of laser light emitted from the LD, which is the light source 111, emitted from the light source 122. Since the laser light is coherent light, for ease of understanding, specific identical phase (wavefront) portions on the optical path of this laser light are sequentially indicated by thick black circles and inclined dashed lines. Also, to clarify the height from the stage 2, contour lines are indicated by dashed lines. Note that the measurement light used in this configuration example of the present disclosure does not particularly need to utilize or detect, for example, a phase change, and therefore may of course be incoherent light.

[0099] In the figure, the coordinates of the bottom directly below the surface point C of the measurement surface 100A of a certain slit light are A = (X0, Ya, Z0), the coordinates of the bottom B facing the stage 2 are B = (X0, Yb, Z0), and the coordinates of the surface point C at the height H to be measured from the stage 2 are C = (X0, Ya, Za). The distance measurement error Δy, which is the deviation in the horizontal (Y) direction of the regular reflected light from points B and C, is expressed in the triangle ABC by the following equation: tanθ=Δy / H (4) (where H is the thickness of the object 100) holds. From equation (4), the desired height H=Δy / tanθ, i.e., equation (3), is derived. Therefore, from equations (1) to (3), the three-dimensional coordinates (X0, Ya, Za) of point C, which includes data about the thickness direction of the measurement surface 100A, are obtained. Note that the X coordinate of point C is set to X=0, but this is not limited to this coordinate position. Any position coordinate in the X direction can be applied to the measurement object 100 on the stage 2.

[0100] In addition to the above, the method of generating three-dimensional data in this configuration example may be a configuration in which a three-dimensional shape is generated by discriminating and extracting regular reflected light from which secondary reflected light has been removed based on differences in phase difference or polarization plane. A configuration example using polarization planes will be described in detail later.

[0101] Therefore, the plane wave (which may be a spherical wave) reaching the measurement surface 100A of the measurement object 100 undergoes a delay in the propagation time t of the plane wave to the light receiving unit depending on the height position of the measurement surface 100A (and simultaneously, a delay in the phase difference, etc.). As a result, a distance measurement error Δy, which is included in the above-described equations (2) and (3), occurs. As a result, the height H of the measurement object can be calculated from this time t and the distance measurement error Δy. Note that, although details are omitted in this disclosure, a time difference may also be generated in the strength E of the electric field reaching the imaging device 122 or the amount of accumulated charge. For example, the height of the measurement object 100 may be measured by utilizing the difference in brightness of each pixel or the difference in the amount of accumulated charge.

[0102] [Effects of this configuration example] Therefore, according to this configuration example, the two image capture devices 122A and 122B, EVS1 and 2, receive specularly reflected light (scattered light), and thus output detection signals with the same shape (height H) from both EVS1 and 2, not only from areas with small shape changes but also from points with large shape (unevenness) changes. Figure 12 is a schematic diagram showing the output distribution of event data for each pixel at a certain time t1. In this diagram, it can be seen that the output states of event data are completely different between the left half area and the right half area.

[0103] However, if there is a single EVS (a single light source is also assumed), it is impossible to determine which is the output of event data generated by a regular signal based on regular reflected light.

[0104] In this configuration example, two imaging devices 122 are used. At a certain point at any time t, when specular reflected light is captured, regardless of whether the reflected light is captured by either EVS1 or 2, the height of the convex part (or the depth of the concave part) at that point obtained from both EVS1 and 2 should be uniquely determined. In other words, it is physically impossible for the height H at the same point to have multiple values. The event data at the same point obtained from both EVS1 and 2 should be the same, and the reflected light that gives a unique input signal value in both EVS1 and 2 is specular reflected light.

[0105] Therefore, in this embodiment, as described above, the above-mentioned calculation formula is used to perform calculations based on data from specular reflected light. This allows for highly accurate shape measurement even at points with large unevenness. Moreover, since the image capture devices 122A and 122B use EVS, it is possible to capture 3D images at high speed.

[0106] As described above, according to this configuration example, the measurement light traveling from the light source 111 in the light source unit 11A to the object 100 is the measurement light traveling along the shortest optical path. After the measurement light is scattered and reflected at a specific position on the measurement surface 100A, which is the measurement point of the object 100 at each time, the measurement light traveling towards the light-receiving unit 12 is configured to use two measurement lights (specular reflected lights) that are reflected and scattered at the same point (same position) and travel different shortest optical paths. This allows accurate measurement of the shape of the measurement surface of the object 100 using the two specular reflected lights having the above-described characteristics, even if the reflected light contains multipath reflected light (i.e., secondary reflected light) and the secondary reflected light is incident on the light-receiving unit 12. In particular, even if the shape has deep irregularities, the shape can be calculated with high accuracy using the above-described arithmetic expressions (1) to (3).

[0107] (2-2. Second configuration example) Next, a second aspect (hereinafter referred to as "second configuration example") of a profile measuring device 10B according to the second embodiment of the profile measuring system of the present disclosure will be described with reference to Figures 13 and 14. Note that the same parts as those in the first configuration example are designated by the same reference numerals to avoid redundant description.

[0108] This configuration example differs from the first configuration example in that the light source unit 11 uses two light sources, a first light source unit 11B and a second light source unit 11C, and a single light receiving unit 12 (hereinafter referred to as light receiving unit 12C). The two light source units, the first light source unit 11B and the second light source unit 11C, are preferably installed apart from each other. For example, they can be installed at opposite positions in the lateral (Y) direction with the light receiving unit 12 at the center. They do not necessarily have to be arranged symmetrically with the light receiving unit 12 at the center. Furthermore, in this configuration example, the control of the control signal transmission unit 131 of the signal processing unit 13 is also different.

[0109] The first light source unit 11B can use, as a light source, a first semiconductor laser (LD1) 111B that continuously oscillates blue laser light with a blue wavelength (λb). The second light source unit 11C can also use, as a light source, a second semiconductor laser (LD2) 111C that has the same wavelength (λb) as the first semiconductor laser (LD1) 111B. The first semiconductor laser (LD1) 111B can be driven to oscillate in a time-division manner with the second semiconductor laser (LD2) 111C in response to a control signal from a control signal transmission unit 131, as will be described in detail later.

[0110] In the first light source section 11B and the second light source section 11C, the cylindrical lens 112 and the scanning mechanism 113 may have the same configuration as those in the first configuration example.

[0111] Each of the light source units 11B and 11C in this example also sequentially sweeps and scans the object 100 in the horizontal (Y) direction. However, in this example, a slit of light is projected sequentially across the entire width in the depth (X) direction for each pixel row (column) at a time interval divided into two. Specifically, as shown in FIG. 14, under the control of the control signal transmitter 131, when projecting each slit of light at a time interval Δt for each pixel row (column), blue laser light of a specific wavelength (λb) is projected from the first light source unit 11B for Δt / 2 seconds. Thereafter, blue laser light of the same wavelength (λb) is projected from the second light source unit 11C for Δt / 2 seconds. These blue laser lights are projected onto the object 100 from light sources 111B and 111C, which are arranged differently.

[0112] On the other hand, the light receiving unit 12C has a single configuration, and the imaging device 122 is an asynchronous type, similar to that in the first configuration example. That is, an EVS (Event-based Vision Sensor) is used, in which pixels that perform photoelectric conversion on incident light reflected by the object 100 are arranged two-dimensionally in a matrix. In this EVS, similar to the first configuration example, the reflected light from the measurement surface of the object 100 is sequentially captured by each pixel constituting the pixel column for each pixel column. Then, based on the captured reflected light, each pixel constituting each pixel column generates a photoelectric conversion signal by photoelectric conversion. The photoelectric conversion signal is output to the event issuing unit 123.

[0113] [Actions and Effects] Therefore, according to this configuration example, the drive time for each of the first and second semiconductor lasers 111B and 111C is divided into two equal parts. In other words, in this configuration example, the slit light projected onto each pixel column is projected twice in the order of the laser light from the first semiconductor laser and the laser light from the second semiconductor laser. These laser lights are cyclically projected sequentially from the start point (Y=0; origin O) in the horizontal (Y) direction of the measurement object 100 to the end point (Y=L; where L is the total horizontal length of the measurement object 100).

[0114] Therefore, according to this configuration example, in the light receiving unit 12, reflected light from the first and second light sources 11B and 11C passes through the lens 121 and sequentially enters the EVS 122 at each pixel column. At this time, in addition to regular reflected light, secondary reflected light may also be input from each light source. Therefore, as in the first configuration example, the unnecessary signal remover 132 removes the electrical signal for the secondary reflected light from the electrical signal output to the signal processing unit 13.

[0115] As described above, in the second configuration example according to the present disclosure, among the reflected light beams (scattered light beams) emitted from the light source units 11B and 11C and reflected by the measurement surface 100A of the object 100, the reflected light beams that follow the shortest path toward the light receiving unit 12 are incident on the light receiving unit 12 as two specular reflected light beams. Furthermore, after being reflected and scattered by the measurement surface 100A, some reflected light beams (secondary reflected light beams) may travel a different optical path, for example, by reflection at another location, before entering the light receiving unit 12. Even if such secondary reflected light beams are incident, according to this configuration example, as in the first configuration example, the data obtained from the two specular reflected light beams are unique, and therefore, unnecessary signals associated with the secondary reflected light beams that generate data different from these data can be subsequently removed by the unnecessary signal removal unit 132.

[0116] As a result, only the normal electrical signals resulting from the regular reflection light of each laser beam are input to the 3D calculation unit 133. The 3D calculation unit 133 calculates, from these normal electrical signals, data in the depth (X) direction on the measurement surface 100A of the measurement object 100 in the same pixel column from any of the laser beams, as well as data in the same height ( H ; or the same deep Such a scan is performed in the lateral (Y) direction of the measurement object 100 from the start point (Y=0) to the end point (Y=L). This makes it possible to obtain a highly accurate three-dimensional shape of the measurement object 100.

[0117] Therefore, according to this configuration example, as in the first configuration example, EVS is used for the imaging device 122, and even if the measurement object 100 has a large unevenness difference, the three-dimensional shape can be detected with high accuracy at high speed.

[0118] (2-3. Third configuration example) Next, a third aspect (hereinafter referred to as "third configuration example") of a profile measuring device 10C according to the profile measuring system of the second embodiment of the present disclosure will be described with reference to Figures 15 and 16. In this configuration example, the same parts as those in the previous configuration example are designated by the same reference numerals to avoid redundant description.

[0119] Similar to the second configuration example, the configuration example of the present disclosure uses two light sources, a first light source 11D and a second light source 11E, but differs from the second configuration example in that light of different wavelengths is emitted from the first light source 11D and the second light source 11E. Furthermore, similar to the second configuration example, in the present configuration example, the signal processing unit 13 controls the laser oscillation operation of each light source in a time-division manner by the control signal transmission unit 131.

[0120] The first light source unit 11D uses a first semiconductor laser (LD1) 111D as a light source, which continuously oscillates blue laser light with a blue wavelength (λb). On the other hand, the second light source unit 11E uses a second semiconductor laser (LD2) 111E as a light source, which continuously oscillates red laser light with a red wavelength (λr; λr>λb).

[0121] The light sources 111D and 111E used in the first and second light source units 11D and 11E may be light sources with the same broadband wavelength (e.g., white LDs). In this case, different color filters may be arranged on each optical path to generate two colors of measurement light. Alternatively, a semiconductor laser capable of wavelength (λ) conversion may be used to convert the wavelength (λ) to distinguish the laser beams. Alternatively, nonlinear frequency (ω) conversion means such as second harmonic generation (SHG) or sum frequency generation (SFG) may be used to distinguish the laser beams.

[0122] In this configuration example, when the first and second light source units 11D and 11E sequentially sweep and scan the object 100 in the horizontal (Y) direction, as in the previous configuration example, when projecting light onto each pixel row (column) at a scanning time interval of Δt seconds, first, blue laser light from the first light source unit 11D is irradiated for Δt / 2 seconds. Immediately thereafter, red laser light is irradiated from the second light source unit 11E for Δt / 2 seconds. Thereafter, a similar scanning operation is repeated sequentially for each pixel row.

[0123] On the other hand, the light receiving unit 12D has a single configuration, and the image capturing device 122 uses an EVS (Event-based Vision Sensor) similar to that of the second configuration example. However, in the EVS of this configuration example, the area corresponding to each pixel column is divided into two sections corresponding to the operating time intervals of each semiconductor laser. As shown in FIG. 16, the first divided section (sometimes referred to as the "blue area") in the first half of the area corresponding to each pixel of each pixel column is provided with blue filters BF1, BF2, BF3, etc. as a first filter that absorbs light of wavelengths other than blue and transmits only blue light. Similarly, the second divided section (sometimes referred to as the "red area") in the second half of each pixel column is provided with red filters RF1, RF2, RF3, etc. as a second filter that transmits only red light and absorbs the remaining light. With this configuration, only the blue laser light from the first semiconductor laser 111D and the red laser light from the second semiconductor laser 111E can be incident separately onto the first and second areas (blue area and red area) of each pixel in each pixel column, respectively.

[0124] [Action and effect] Therefore, according to this configuration example, the drive time for the first and second semiconductor lasers 111D, 111E is divided into two equal parts. That is, in this configuration example, slit light for each column is projected in color, starting from blue to red. These two-color laser light beams are cyclically repeated from the start point (Y=0; origin O) in the horizontal (Y) direction of the measurement object 100 to the end point (Y=L; where L is the total horizontal length of the measurement object 100).

[0125] In particular, in this configuration example, only blue laser light from the first semiconductor laser 111D and red laser light from the second semiconductor laser 111E are permitted to enter the first and second areas (blue and red areas) of each pixel in each pixel column, respectively. Therefore, in the light receiving unit 12, even if the blue and red reflected light pass through the lens 121 and enter a single EVS 122, mixing and superimposing each other to form a purple or other color, and then entering each pixel column, unnecessary wavelength light is removed by each color filter, i.e., the first blue filters BF1, BF2, BF3, . . . and the second red filters RF1, RF2, RF3, . . . . As a result, only laser light of the desired wavelength can be incident on each predetermined area sequentially. In this case, even if laser light of the same color is selectively incident on each color area within each pixel, there is a possibility that secondary reflected light of the same color, which is permitted, may also be incident simultaneously. Therefore, even if such secondary reflected light of the same color is incident on a same-color area, the photoelectrically converted electrical signal output from the EVS to the signal processing unit 13 can have the electrical signal of the secondary reflected light associated with each same-color laser light removed by the unnecessary signal removal unit 132.

[0126] Furthermore, in the third configuration example according to the present disclosure, as in the second configuration example described above, among the reflected light (scattered light) emitted from each light source unit 11D, 11E and reflected by the measurement surface 100A of the measurement object 100, the reflected light that follows the shortest path toward the light receiving unit 12 is incident on the light receiving unit 12D as two types of regular reflected light. Meanwhile, in this configuration example, there may also be reflected light (secondary reflected light) that is reflected and scattered by the measurement surface 100A, and then reflected along another optical path, etc., and then incident on the light receiving unit 12D. Even when such secondary reflected light is incident, according to this configuration example, as in the second configuration example, the unnecessary signal caused by the secondary reflected light can be removed by the unnecessary signal removal unit 132.

[0127] As a result, the 3D calculation unit 133, which receives only the normal electrical signals associated with the two-color laser beams, calculates the three-dimensional shape from the two types of normal electrical signals using the above-mentioned calculation formula. From either laser beam, a value that gives the same height (H; or the same depth) on the measurement surface 100A of the measurement object 100 can be obtained in the same pixel column. By performing this operation in a sweeping manner across the measurement object 100 from the start point (Y=0) to the end point (Y=L), a highly accurate three-dimensional shape of the measurement object 100 can be obtained.

[0128] Therefore, according to this configuration example, similar to the first and second configuration examples, even if the measurement object 100 has a large unevenness difference, the three-dimensional shape can be detected with high accuracy at high speed by using EVS for the imaging device 122C.

[0129] Furthermore, in this example configuration, the EVS is configured to allow laser light of different wavelengths to be incident on designated areas divided into two, each corresponding to a different wavelength, for each pixel row. Therefore, even if ambient light, such as purple light (a mixture of blue and red light) in a certain pixel row, attempts to enter a designated area of ​​the EVS pixel row covered by a blue filter BF, it is blocked by the blue filter BF. Therefore, only reflected light from the blue laser light can be incident on the designated area of ​​that pixel row. The same is true for pixel rows covered by a red filter RF. This enables accurate measurement of three-dimensional shapes.

[0130] (2-4. Fourth Configuration Example) Next, a fourth aspect (hereinafter referred to as "fourth configuration example") of a profile measuring device 10D according to the profile measuring system of the second embodiment of the present disclosure will be described with reference to Figures 17 to 19. In this configuration example, the same parts as those in the previous configuration example are designated by the same reference numerals to avoid redundant description.

[0131] This configuration example differs from the third configuration example in that the light sources 111F and 111G of the first light source unit 11F and the second light source unit 11G use semiconductor lasers LD1 and LD2, respectively, that emit laser light of the same wavelength (λ. Also, unlike the third configuration example, the first light source unit 11F and the second light source unit 11G are provided with polarizers 114 and 115, respectively, that have different predetermined functions. Note that the LD1 and LD2 may be entirely different types of LDs that emit laser light of different wavelengths, rather than the same wavelength.

[0132] [1st and 2nd light source section] The semiconductor laser LD1 oscillates and emits laser light having a specific wavelength (λ) that is approximately circularly polarized (or may be elliptically polarized). The LD2 also oscillates and emits laser light having the same wavelength as the semiconductor laser LD1 that is approximately circularly polarized (or elliptically polarized). The wavelengths of the laser light emitted from these lasers are not particularly limited, and any wavelength can be selected.

[0133] In the first light source unit 11F, unlike the third configuration example, in order to emit vertically polarized laser light, the above-mentioned first polarizer 114 is provided on the optical path (optical axis A1) immediately after LD1 shown in Fig. 18A, and the polarization plane is shaped from circularly polarized (or elliptically polarized) to vertically polarized light (hereinafter, sometimes referred to as "P wave"). Similarly, in the second light source unit 11G, unlike the third configuration example, in order to emit horizontally polarized laser light, the above-mentioned second polarizer 115 is provided on the optical path (optical axis A2) immediately after LD2 shown in Fig. 18B, and the polarization plane is shaped from circularly polarized (or elliptically polarized) to horizontally polarized light (hereinafter, sometimes referred to as "S wave").

[0134] [Light receiving section] On the other hand, in the light receiving unit 12E of this configuration example, the area corresponding to each pixel column in the EVS is divided into two regions, i.e., first and second divided regions, so that only P waves and S waves are incident thereon, in the same pattern as in the third configuration example, as shown in Fig. 19. Specifically, in the first divided region (hereinafter referred to as the "P-wave area") and the second divided region (hereinafter referred to as the "S-wave area"), which are two divided areas corresponding to each pixel in each pixel column of the EVS, films having the same functions as the first polarizer 114 and the second polarizer 115, i.e., vertical polarizing films FP1, FP2, FP3... as the first film and horizontal polarizing films FS1, FS2, FS3... as the second film, are installed according to each area.

[0135] Therefore, in this configuration example, as in the third configuration example, only vertically polarized laser light from the first semiconductor laser and horizontally polarized laser light from the second semiconductor laser can be incident on the corresponding areas in the first and second halves of each pixel column, respectively. Therefore, in the light receiving unit 12, even if the laser light that passes through the lens 121 and enters the single EVS 122 for each pixel column contains a mixture of vertical and horizontal polarization planes, the vertical polarizing film FP and horizontal polarizing film FS, which function equivalent to each polarizer, remove laser light with unnecessary polarization planes, such as unnecessary secondary reflected light. This allows only laser light with the necessary polarization plane to be incident on each area of ​​each pixel column of the EVS.

[0136] Furthermore, in the fourth configuration example according to the present disclosure, as in the third configuration example described above, among the reflected light (scattered light) emitted from each light source unit 11F, 11G and reflected by the measurement surface 100A of the measurement object 100, the reflected light that follows the shortest path toward the light receiving unit 12 is incident on the light receiving unit 12E as two types of regular reflected light. Meanwhile, in this configuration example, there may also be reflected light (secondary reflected light) that, after being reflected and scattered by the measurement surface 100A, travels a different optical path, for example, by reflecting at another point, and then enters the light receiving unit 12E. Even in such a case, as in the first to third configuration examples, the unnecessary signal generated in association with the secondary reflected light can be removed by the unnecessary signal removal unit 132.

[0137] Therefore, according to this configuration example, as with the first configuration example, even if the measurement object 100 has a large unevenness difference, vertically polarized laser light and horizontally polarized laser light can be incident on designated areas within each pixel, with only laser light with a designated polarization plane. This allows for highly accurate detection of three-dimensional shapes. Moreover, this configuration example also uses an EVS as the imaging device, making it possible to measure three-dimensional shapes at high speed.

[0138] (2-5. Fifth Configuration Example) Next, a fifth aspect (hereinafter referred to as "fifth configuration example") of a profile measuring device 10E according to the second embodiment of the present disclosure will be described in detail with reference to Figures 20 to 22. In this configuration example, the same parts as those in the previous configuration example are designated by the same reference numerals to avoid redundant description.

[0139] This configuration example differs from the previous configuration examples in that there is only one light source unit 11H, and light source unit 11H includes LD 111H that emits white light, cylindrical lens 112, scanning mechanism 113, and also includes a spectroscopic prism 116, and there is only one light receiving unit 12F, and there is a color filter 125 that selectively transmits light of three color wavelength bands, namely, red (hereinafter sometimes abbreviated as “R”), green (hereinafter sometimes abbreviated as “G”), and blue (hereinafter sometimes abbreviated as “B”) wavelengths, located immediately before lens 121 on the reflected light path from light receiving unit 12F. Note that this color filter 125 is composed of a first filter (hereinafter referred to as “filter R”) having a wavelength transmission characteristic that transmits only R, a second filter (hereinafter referred to as “filter G”) having a wavelength transmission characteristic that transmits only G, and a third filter (hereinafter referred to as “filter B”) having a wavelength transmission characteristic that transmits only B.

[0140] [Light source section] The light source 111H preferably has a wide wavelength range. In this configuration example, a semiconductor laser (hereinafter, sometimes referred to as "white semiconductor laser 111H") is used that emits white laser light with an oscillation wavelength range covering the visible light range of 380 nm to 760 nm. Note that the light source 111H can be, as long as it emits light over a wide range, for example, a white LED in which a blue LED is coated with a phosphorescent material to convert part of the blue light into green, yellow, and red light, but a light source with high brightness and directionality is preferable.

[0141] Prism 116 splits the white light emitted from white semiconductor laser 111H into seven colors. After passing through prism 116 in this configuration example, the laser light is split into seven colors due to the difference in refractive index at each wavelength.

[0142] As shown in FIG. 21, the prism 116 of this configuration example is configured to separate and split incident light into three broad wavelength bands (R, G, and B wavelength bands). These three types of incident light α are blue incident light (hereinafter referred to as B light: α) of approximately 380 to 500 nm. B ), 500-580 nm green incident light (hereinafter referred to as G light: α G ), and red incident light of 580 to 760 nm (hereinafter referred to as R light: α R In the present disclosure, it is also possible to separate or divide visible light with a wavelength range of, for example, 380 nm to 760 nm into smaller groups. In that case, it is preferable to use color filters on the light receiving section side, which will be described later, that have the same wavelength transmission characteristics.

[0143] [Light receiving section] The light receiving unit 12F basically has the same configuration as the first and second configuration examples described above, but further includes a color filter 125 as shown in Figures 20 and 22, as described above. As is well known, light of the same wavelength (light incident on the light receiving unit 12F) travels toward and is incident on the measurement surface of the object, following a specific optical path (a uniquely determined shortest optical path) which is the shortest optical distance, in accordance with Fermat's principle (principle of least action). Furthermore, the basic principle is that the reflected light after being reflected there returns in the same direction, following the same optical path (shortest optical path) as the incident light, which is the shortest optical distance (reversibility of light).

[0144] This principle is utilized in the configuration example of the present disclosure. As a result, regular incident light becomes regular reflected light and is incident on each pixel column of the EVS 122. That is, regular reflected light of each color of RGB can be incident on the corresponding same wavelength area in a three-divided region equipped with the same RGB color filter 125 (i.e., filter R, filter G, filter B). The color filters 125 can be fixed in the housing 14 (see FIG. 20) that houses the light receiving unit 12, thereby forming a unit or module as a light receiving function unit. Furthermore, if the color filter 125 is a thin film, it may be directly attached to the lens 121.

[0145] To more effectively utilize the wavelength transmission characteristics of the color filter 125 and ensure its ability to capture regular reflected light, it is preferable to use a lens with high collimating capability for the lens 121 immediately behind the color filter 125, so that light passing through each color filter portion travels directly to the same pixel in the pixel row. Examples of such a lens include a SELFOC (registered trademark) lens and a collimator. This allows, for example, the return light of the B component incident on and passing through filter B of the color filter 125 to pass through the lens 121 as collimated light and then enter the corresponding pixel portion of the EVS 122 without shifting its position relative to the pixel in the depth (X) direction within the pixel row. The color filter 125 also has a similar effect on the return light of other color components (R and G).

[0146] [Action and effect] 20 and 22, the light of each wavelength of RGB emitted from light source unit 11H, split, and projected onto measurement object 100 is reflected by measurement surface 100A and then incident on color filter 125. As shown in Fig. 21, the slit light, which is laser light of 380 to 760 nm emitted from light source unit 11H and split into RGB, is reflected by measurement surface 100A. Of the reflected light beams, the specular reflected light beam travels the shortest path with the shortest optical distance compared to the other reflected light beams and returns toward color filter 125.

[0147] Each specularly reflected light of RGB incident on the color filter 125 may not only be incident on an area of ​​the same color component, but also on an area of ​​another color component. B Even if the reflected light of the B component that has passed through filter B enters an area of ​​a color component different from that of filter B (i.e., filter R or filter G), it will be absorbed by filter R or filter G in these areas. Therefore, it will not enter a pixel corresponding to R light or G light. In this way, only the reflected light of the B component that has passed through filter B can enter the specific pixel corresponding to this filter B. For this reason, with regard to the specularly reflected light of RGB, even if returning light of a different RGB color component becomes stray light and strays into another RGB area, it will be absorbed without passing through color filter 125.

[0148] Therefore, according to the fifth configuration example, only specularly reflected light from a specific area of ​​the measurement surface corresponding to that pixel can be incident on each pixel in each pixel row. This eliminates the risk of data relating to the shape of other areas within the measurement surface being mixed in, making it possible to perform accurate shape measurement. Furthermore, image information is generated using specularly reflected light that is reflected by each reflecting surface. Therefore, even if the measurement surface has a shape with large unevenness, an accurate measurement surface shape can be generated.

[0149] That is, in the fifth configuration example according to the present disclosure, as in the previous configuration example, each of the RGB reflected light (scattered light) emitted from the light source unit 11H is separated by the prism 116, travels along different optical paths, and is reflected and scattered by the measurement surface 100A of the object 100. The reflected light travels the shortest path toward the light-receiving unit 12F and enters the light-receiving unit 12F as specularly reflected light of RGB. Meanwhile, in this configuration example, there may also be reflected light (secondary reflected light) that, after being reflected and scattered by the measurement surface 100A, travels along a different optical path, for example, by reflecting off another part, and then enters the light-receiving unit 12F. Even if such reflected light exists, as in the previous configuration example, the data obtained from the specularly reflected light among the reflected light captured by each RGB pixel area 122 is unique. Therefore, in each RGB pixel area 122, unwanted signals associated with the secondary reflected light that generate data different from this data can then be removed by the unwanted signal removal unit 132.

[0150] As described above, according to this configuration example, with regard to secondary reflected light, the color filter 125 has a similar effect to that on regular reflected light, which may allow secondary reflected light of the same color component to be transmitted into an area of ​​the same color component. However, even if an unwanted signal is generated from this secondary reflected light, this signal can be removed by the unwanted signal removal section 132 of the signal processing unit 13, as described above. As a result, even if secondary reflected light, which is light from another RGB and which may cause erroneous data, enters the EVS 122 in each RGB pixel area 122, this can be effectively removed.

[0151] Above, each embodiment and each configuration example of the shape measurement system according to the present disclosure have been described. Finally, the description of each embodiment and each configuration example described above is an example of the present disclosure, and the present disclosure is not limited to the above-described embodiment and each configuration example. Therefore, even if it is not each embodiment and each configuration example described above, various modifications are naturally possible depending on the design, etc., as long as they do not deviate from the technical idea of ​​the present disclosure. Furthermore, the effects described in this specification are merely examples and are not limited. Furthermore, other effects may also be obtained.

[0152] It should be noted that the drawings in the above-described embodiments and each configuration example are schematic, and the dimensional ratios of each part may not necessarily correspond to the actual ones. Furthermore, it goes without saying that the drawings also include parts with different dimensional relationships and ratios. Furthermore, as for the vibration state of the light wave of the measurement light described in the above-described embodiments and each configuration example, various modes such as circular polarization, elliptically polarization, and linear polarization can be applied as long as the same effect can be obtained.

[0153] Furthermore, as mentioned above, the shape measurement system of the present disclosure is not limited to applications such as measuring the shapes of numerous products sent out one after another in a factory, for example. That is, the system of the present disclosure may be used to capture temporal changes when observing, monitoring, or measuring a single static or dynamic object or a specific target area. For example, it can also be applied as a fixed-point observation and monitoring system, such as a surveillance camera in a train station, a camera in a parking lot, or an in-vehicle camera.

[0154] 3. Configurations that the present disclosure can take The present disclosure may also be configured as follows. (1) a light source unit that emits measurement light to a measurement object; a light receiving unit that receives the reflected light of the measurement light reflected from the measurement object, a three-dimensional shape calculation unit that calculates the three-dimensional shape of the measurement object from event data generated from the reflected light that is reflected from the measurement object and incident on the light receiving unit, and a signal processing unit that has an unnecessary signal removal unit that removes unnecessary signals generated when unnecessary light other than the reflected light is incident on the light receiving unit from the outside; a scanning mechanism that scans the measurement object by sweeping the measurement light projected from the light source unit onto the measurement object by moving the light source unit or the measurement object; A shape measurement system comprising: (2) the scanning mechanism is provided in the light source unit, the light source unit includes a light source and a waveform control lens that controls the waveform of light from the light source; The shape measurement system described in (1) above, wherein the light receiving unit comprises a light receiving lens, an EVS (Event-based Vision Sensor) which is an asynchronous imaging element that captures temporal changes in the reflected light that passes through the light receiving lens and outputs an event signal, an event issuing unit that detects events based on output data from the EVS and outputs event data, and a transmitting unit that outputs the event data to the signal processing unit. (3) The light source unit is a single unit, The shape measurement system according to (2) above, comprising a first light receiving unit and a second light receiving unit that are positioned offset from each other as the light receiving unit. (4) The light source unit includes a first light source unit and a second light source unit that are installed at positions shifted from each other, the light receiving unit is a single unit, The shape measurement system according to (2), wherein the signal processing unit includes a control signal transmission unit that outputs a control signal to each of the scanning mechanisms at time intervals that are time-divided for each pixel column. (5) The light source unit includes a first light source unit having a first light source that emits light of a first wavelength, and a second light source unit having a second light source that emits light of a second wavelength, the light receiving unit is a single unit, The EVS is configured by two divided areas, which are divided into a first divided area and a second divided area in units of pixel columns, and The first divided area includes a first filter having a first wavelength transmission characteristic that selectively transmits the reflected light of the first wavelength among the light of the first wavelength and the reflected light of the second wavelength that are reflected by the measurement object, among the measurement light of two different wavelengths emitted from the light source; The shape measurement system described in (2), wherein the second division area is provided with a second filter having a second wavelength transparency that selectively transmits light of the second wavelength in the reflected light. (6) the light of the first wavelength is light of a blue wavelength, The shape measurement system according to (5), wherein the light of the second wavelength is light of a red wavelength. (7) The light source unit includes a first light source unit including the first light source and a second light source unit including a second light source, the first light source unit includes a first optical element that generates a first measurement light having a first polarization plane from light emitted from the first light source; the second light source unit includes a second optical element that generates second measurement light having a second polarization plane from the light emitted from the second light source; the light receiving unit is a single unit, The EVS is divided into two regions, a first divided region and a second divided region, for each pixel column; the first divided region includes a first film that selectively transmits the first reflected light having the first polarization plane and the second reflected light having the second polarization plane, which are reflected by the measurement object and incident on the light receiving unit, respectively, of the two types of measurement light, the first measurement light and the second measurement light; The shape measurement system according to (2), wherein the second divided region includes a second film that selectively transmits the second reflected light. (8) The shape measurement system according to (7), wherein the first polarization plane is linearly polarized light that oscillates in a vertical direction, and the second polarization plane is linearly polarized light that oscillates in a horizontal direction. (9) The light source unit is a single unit, a light source in the light source unit includes a splitting means for splitting light from the light source into at least three wavelength bands; the light receiving unit is a single unit, The EVS is configured by three divided regions, which are divided into first to third divided regions in pixel column units, the first divided region is provided with a first color filter having wavelength transmission characteristics that selectively transmits reflected light of a first wavelength band among reflected light of three wavelength bands reflected by the measurement object, among measurement light of three different wavelength bands emitted from the light source; the second divided region is provided with a second color filter having wavelength transmission characteristics that selectively transmits reflected light in a second wavelength band among the reflected light in three wavelength bands that is reflected by the object to be measured, The shape measurement system described in (2) above, wherein the third divided area is provided with a third color filter having wavelength transmission characteristics that selectively transmits reflected light of a third wavelength band among the reflected light of three different wavelength bands reflected by the object to be measured. (10) The splitting means is composed of a prism that splits the white light from the light source into light of three different wavelength bands, The three wavelength bands of light are red wavelength band light, green wavelength band light, and blue wavelength band light. The shape measurement system according to (9) above. (11) The EVS compares a signal voltage based on the temporal change of the reflected light with a threshold voltage, and outputs an event signal by determining whether the signal voltage is smaller or larger than the threshold voltage. The shape measurement system according to (2) above. [Explanation of symbols]

[0155] 1. Shape measurement system 2 Stage (measuring table) 3. Movement mechanism (scanning mechanism) 4. Control section 10, 10A~10E Shape measuring device 11 Light source section 11A 1st light source section 11B 2nd light source section 11D 1st light source section 11E 2nd light source section 11F Light source section 111 Light source: Semiconductor laser (LD) 111A First semiconductor laser (LD1) 111B Second semiconductor laser (LD2) 111C Third semiconductor laser (LD3) 111F LD 112 Cylindrical lens (waveform forming lens, waveform control lens) 113 Scanning mechanism 114 First polarizer (optical element) 115 Second polarizer (optical element) 116 Prism 12, 12C, 12D, 12E, 12F light receiving section 12A 1st light receiving section 12B 2nd light receiving section 121 Receiving lens 122, 122A, 122B Asynchronous (non-scanning) imaging device (imaging element) (EVS, EVS1, EVS2) 123 Event Publishing Department 124 Transmitter 13 Signal processing unit (signal processing section) 131 Control signal transmitter 132 Unnecessary signal removal section 133 3D calculation section 134 memory 21 Imaging unit 211 Pixel array section 212 Drive unit 213 Arbitration Department 214 Column processing section 215 Signal Processing Unit 210 pixels 41 System control unit 42 Movement control unit 51 Photoelectric conversion unit 52 Pixel signal generation unit 53 Address event detector 513 OFG transistor 531 Current-to-voltage conversion unit 532 buffers 533 Subtractor 534 Quantizer 535 Transfer Department 100 Measurement object 100A measuring surface A1, A2 optical axis BF Blue filter (first filter) RF red filter (second filter) FP vertical polarizing film (first film) FS Horizontal Polarizing Film (Second Film) FR Filter R (1st filter) FG Filter G (second filter) FB Filter B (3rd filter) H Head X depth direction Y horizontal direction Z height direction α Incident light (measurement light) αR Red incident light (R light) α G Green incident light (G light) α B Cyan incident light (B-beam) β reflected light β1 reflected light β2 reflected light

Claims

1. a light source unit that emits measurement light to a measurement object; a light receiving unit that receives reflected light of the measurement light reflected from the measurement object; a signal processing unit including a three-dimensional shape calculation unit that calculates a three-dimensional shape of the measurement object based on event data generated from the reflected light that is reflected from the measurement object and incident on the light receiving unit, and an unnecessary signal removal unit that removes unnecessary signals generated when unnecessary light other than the reflected light is incident on the light receiving unit from the outside; a scanning mechanism that scans the measurement object by sweeping the measurement light projected from the light source unit onto the measurement object by moving the light source unit or the measurement object; Equipped with the scanning mechanism is provided in the light source unit, the light source unit includes a light source and a waveform control lens that controls the waveform of light from the light source; the light receiving unit includes a light receiving lens; an EVS (Event-based Vision Sensor) which is an asynchronous imaging element that captures a temporal change in the reflected light that passes through the light receiving lens and outputs an event signal; an event issuing unit that detects an event based on output data from the EVS and outputs event data; and a transmitting unit that outputs the event data to the signal processing unit; The light source unit includes a first light source unit and a second light source unit, the signal processing unit includes a control signal transmission unit that outputs a control signal to each of the scanning mechanisms at time-divided time intervals for each pixel column; Shape measurement system.

2. a light source unit that emits measurement light to a measurement object; a light receiving unit that receives reflected light of the measurement light reflected from the measurement object; a signal processing unit including a three-dimensional shape calculation unit that calculates a three-dimensional shape of the measurement object based on event data generated from the reflected light that is reflected from the measurement object and incident on the light receiving unit, and an unnecessary signal removal unit that removes unnecessary signals generated when unnecessary light other than the reflected light is incident on the light receiving unit from the outside; a scanning mechanism that scans the measurement object by sweeping the measurement light projected from the light source unit onto the measurement object by moving the light source unit or the measurement object; Equipped with the scanning mechanism is provided in the light source unit, the light source unit includes a light source and a waveform control lens that controls the waveform of light from the light source; the light receiving unit includes a light receiving lens; an EVS (Event-based Vision Sensor) which is an asynchronous imaging element that captures a temporal change in the reflected light that passes through the light receiving lens and outputs an event signal; an event issuing unit that detects an event based on output data from the EVS and outputs event data; and a transmitting unit that outputs the event data to the signal processing unit; the light source unit includes a first light source unit having a first light source that emits light of a first wavelength, and a second light source unit having a second light source that emits light of a second wavelength, The EVS is configured by two divided areas, which are divided into a first divided area and a second divided area in units of pixel columns, and The first divided area includes a first filter having a first wavelength transmission characteristic that selectively transmits the reflected light of the first wavelength among the light of the first wavelength and the reflected light of the second wavelength that are reflected by the measurement object, among the measurement light of two different wavelengths emitted from the light source; the second division area includes a second filter having a second wavelength transmittance that selectively transmits light of the second wavelength in the reflected light; Shape measurement system.

3. the light of the first wavelength is light of a blue wavelength, the second wavelength light is red wavelength light; The shape measurement system of claim 2 .

4. a light source unit that emits measurement light to a measurement object; a light receiving unit that receives reflected light of the measurement light reflected from the measurement object; a signal processing unit including a three-dimensional shape calculation unit that calculates a three-dimensional shape of the measurement object based on event data generated from the reflected light that is reflected from the measurement object and incident on the light receiving unit, and an unnecessary signal removal unit that removes unnecessary signals generated when unnecessary light other than the reflected light is incident on the light receiving unit from the outside; a scanning mechanism that scans the measurement object by sweeping the measurement light projected from the light source unit onto the measurement object by moving the light source unit or the measurement object; Equipped with the scanning mechanism is provided in the light source unit, the light source unit includes a light source and a waveform control lens that controls the waveform of light from the light source; the light receiving unit includes a light receiving lens; an EVS (Event-based Vision Sensor) which is an asynchronous imaging element that captures a temporal change in the reflected light that passes through the light receiving lens and outputs an event signal; an event issuing unit that detects an event based on output data from the EVS and outputs event data; and a transmitting unit that outputs the event data to the signal processing unit; The light source unit includes a first light source unit having a first light source and a second light source unit having a second light source, the first light source unit includes a first optical element that generates a first measurement light having a first polarization plane from light emitted from the first light source; the second light source unit includes a second optical element that generates second measurement light having a second polarization plane from the light emitted from the second light source, The EVS is divided into two regions, a first divided region and a second divided region, for each pixel column; the first divided region includes a first film that selectively transmits the first reflected light having the first polarization plane and the second reflected light having the second polarization plane, which are reflected by the measurement object and incident on the light receiving unit, respectively, of the two types of measurement light, i.e., the first measurement light and the second measurement light; the second division region includes a second film that selectively transmits the second reflected light; Shape measurement system.

5. the first polarization plane is linearly polarized light vibrating in a vertical direction, the second polarization plane is linearly polarized light vibrating in the horizontal direction; The shape measurement system according to claim 4 .

6. a light source unit that emits measurement light to a measurement object; a light receiving unit that receives reflected light of the measurement light reflected from the measurement object; a signal processing unit including a three-dimensional shape calculation unit that calculates a three-dimensional shape of the measurement object based on event data generated from the reflected light that is reflected from the measurement object and incident on the light receiving unit, and an unnecessary signal removal unit that removes unnecessary signals generated when unnecessary light other than the reflected light is incident on the light receiving unit from the outside; a scanning mechanism that scans the measurement object by sweeping the measurement light projected from the light source unit onto the measurement object by moving the light source unit or the measurement object; Equipped with the scanning mechanism is provided in the light source unit, the light source unit includes a light source and a waveform control lens that controls the waveform of light from the light source; the light receiving unit includes a light receiving lens; an EVS (Event-based Vision Sensor) which is an asynchronous imaging element that captures a temporal change in the reflected light that passes through the light receiving lens and outputs an event signal; an event issuing unit that detects an event based on output data from the EVS and outputs event data; and a transmitting unit that outputs the event data to the signal processing unit; a light source in the light source unit includes a splitting means for splitting light from the light source into at least three wavelength bands; The EVS is configured by three divided regions, which are divided into first to third divided regions in pixel column units, The first divided region includes a first filter having wavelength transmission characteristics that selectively transmits reflected light of a first wavelength band among reflected light of three wavelength bands reflected by the measurement object, among measurement light of three different wavelength bands emitted from the light source; the second divided region is provided with a second filter having wavelength transmission characteristics that selectively transmits reflected light in a second wavelength band among reflected light in three types of wavelength bands that is reflected by the measurement object, The third divided region is provided with a third filter having wavelength transmission characteristics that selectively transmits reflected light in a third wavelength band among reflected light in three types of wavelength bands reflected by the measurement object. Shape measurement system.

7. the splitting means is configured by a prism that splits the white light from the light source into light of three different wavelength bands, The three types of wavelength band light are light in a red wavelength band, light in a green wavelength band, and light in a blue wavelength band. The shape measurement system according to claim 6 .

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