Detection device, detection program, and optical device

Abstract

To suppress an influence of light other than direct light when detecting an object to be detected by detecting reflected light of light emitted to the object to be detected from a light-emitting element array including a plurality of light-emitting elements, as compared with a case where the light other than the direct light that is directly incident on and reflected by the object to be detected is not considered.SOLUTION: A detection apparatus comprises: a light-emitting element array including a plurality of light-emitting elements; a light-receiving element array including a plurality of light-receiving elements that receive reflected light of light emitted from the light-emitting element array to an object to be detected; a drive section that selectively drives the plurality of light-emitting element arrays; and a detection section that causes a light-emitting element other than the light-emitting elements which irradiate a light-receiving element with light other than direct light to emit light, and detects the object to be detected from received light amounts of light received by the light-receiving elements when there are the light-receiving elements which receive the light other than the direct light directly reflected by the light-receiving elements from the object to be detected.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a detection device, a detection program, and an optical device. [Background technology]

[0002] Patent document 1 discloses a method for measuring depth that is insensitive to corrupted light caused by internal reflection, the method including: emitting light into a scene by a light source; performing corrupted light measurement by controlling a first charge storage unit of the pixel to collect charge based on light impinging on the pixel during a first period when corrupted light impinges on the pixel but returned light from an object within the field of view of the pixel does not impinge on the pixel; removing, based on the corrupted light measurement, contributions from the corrupted light from one or more measurements affected by the corrupted light; and determining the depth based on the one or more measurements from which the contributions from the corrupted light have been removed.

[0003] Patent Document 2 discloses a distance measurement device comprising a light-projecting unit that projects light onto an object, a light-receiving unit that receives light reflected or scattered by the object, a scanning unit that scans a scanning area with the light projected from the light-projecting unit, and a distance measurement unit that measures the time from when the light is projected by the light-projecting unit to when the light is received by the light-receiving unit, and measures the distance to the object; the scanning area is divided into a plurality of divided areas, and one scan is defined as the period from when scanning one of the divided areas begins to when scanning all of the divided areas is completed.The distance measurement unit determines whether the measurement value of the first divided area can be used as the measurement result for the first divided area based on the measurement value of the first divided area and the measurement value of a second divided area measured before the measurement value of the first divided area, and if it is determined that the measurement value of the first divided area can be used as the measurement result for the first divided area, outputs the measurement value of the first divided area as the distance to the object in the first divided area.

[0004] Patent Document 3 discloses an optical flight-type distance measuring device comprising: a first light source that emits a first light into a first light-emitting space; a light-receiving unit having a plurality of pixels that receive light at each pixel; a distance image acquisition unit that acquires a distance image showing the distance from the device to the object for each pixel by receiving light, including first reflected light that is formed when the first light is reflected from the surface of the object, at the light-emitting unit during an emission period when the first light is repeatedly emitted from the first light source; a brightness value image acquisition unit that acquires a brightness value image showing the brightness value for each pixel by receiving light, including second reflected light that is formed when second light is emitted from a second light source into a second light-emitting space that includes at least a part of the first light-emitting space so that the optical axis is different from that of the first light, at the light-receiving unit during a non-emission period when the first light is not repeatedly emitted from the first light source; and a multipath detection unit that uses the distance image and the brightness value image to detect areas where multipath occurs.

[0005] Patent Document 4 discloses a distance measurement device that includes an emitter that emits a search light and a receiver that receives the reflected light of the search light, and that measures the distance to an object that reflects the search light based on the reflected light received by the receiver. The distance measurement device is characterized in that a strong scattering region is defined as an area centered on the emitter where the intensity of scattered light generated when the search light passes through or is reflected by water droplets with a diameter larger than the wavelength of the search light exceeds the noise level of the receiver, and the receiver is installed at a position outside the strong scattering region, and a shading means is provided to block converging scattered light that converges in a specific direction and scattered light that attempts to enter the receiver at an angle of incidence larger than the converging scattered light. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2019-219400 [Patent Document 2] Japanese Patent Application Publication No. 2019-028039 [Patent Document 3] Japanese Patent Application Laid-Open No. 2017-15448 [Patent Document 4] Japanese Patent Application Laid-Open No. 2007-333592 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention aims to provide a detection device, a detection program, and an optical device that can suppress the influence of light other than direct light when detecting a detection target by detecting reflected light of light emitted toward the detection target from a light-emitting element array having a plurality of light-emitting elements, compared to when light other than direct light that is directly incident on the detection target and reflected is not taken into consideration. [Means for solving the problem]

[0008] The detection device according to the first aspect comprises a light-emitting element array having a plurality of light-emitting elements, a light-receiving element array having a plurality of light-receiving elements that receive reflected light of light emitted from the light-emitting element array toward the object to be detected, a drive unit that selectively drives a plurality of the light-emitting element arrays, and a detection unit that, if there is a light-receiving element that receives light other than direct light that is directly reflected from the object to be detected onto the light-receiving element, causes a light-emitting element other than the light-emitting element that irradiated the light other than direct light onto the light-receiving element to emit light and detects the object to be detected from the amount of light received by the light-receiving element.

[0009] The detection device of the second aspect is the detection device of the first aspect, in which the detection unit causes all of the light-emitting elements to emit light, and detects the object to be detected by causing the light-emitting elements corresponding to the light-receiving elements that have received an amount of light less than a predetermined threshold out of the amount of light received by all of the light-receiving elements to emit light.

[0010] A detection device according to a third aspect is the detection device according to the second aspect, wherein the detection unit detects the object to be detected by causing the light-emitting element corresponding to the light-receiving element that receives an amount of light greater than or equal to the threshold to emit light a number of times less than the number of times that the light-emitting element corresponding to the light-receiving element that receives an amount of light less than the threshold emits light.

[0011] A detection device according to a fourth aspect is a detection device according to the third aspect, wherein the detection unit concurrently emits light from the light-emitting element corresponding to a light-receiving element that receives an amount of light less than the threshold value and emits light from the light-emitting element corresponding to a light-receiving element that receives an amount of light greater than or equal to the threshold value.

[0012] The detection device of the fifth aspect is the detection device of the first aspect, wherein the detection unit individually causes the plurality of light-emitting elements to emit light, and when light is received by a second light-receiving element other than the first light-receiving element corresponding to the first light-emitting element that emitted light, the detection unit does not cause the second light-emitting element corresponding to the second light-receiving element to emit light, but causes the first light-emitting element corresponding to the first light-receiving element to emit light, thereby detecting the object to be detected.

[0013] A detection device according to a sixth aspect is a detection device according to the first aspect, in which the detection unit causes all of the light-emitting elements to emit light, measures the distance to the object to be detected from the amount of light received by all of the light-receiving elements, and detects the object to be detected by causing light-emitting elements other than the light-emitting element that irradiates light to the light-receiving element in the area where the distance changes continuously to emit light.

[0014] A detection device according to a seventh aspect is a detection device according to the first aspect, in which the detection unit detects the object to be detected by individually causing the plurality of light-emitting elements to emit light in accordance with the emission order of the plurality of light-emitting elements set from a light-receiving amount map of the amount of light received by the plurality of light-receiving elements.

[0015] The detection device according to an eighth aspect is the detection device according to the seventh aspect, wherein the detection section causes each pair of the light-emitting elements to emit light in a combination that does not cause mutual interference of light based on the received light amount map.

[0016] A detection device according to a ninth aspect is the detection device according to the first aspect, wherein the detection unit individually causes the plurality of light-emitting elements to emit light and individually detects the object to be detected from the amount of light received by the light-receiving elements corresponding to the light-emitting elements that emitted light.

[0017] A detection device according to a tenth aspect is the detection device according to the first aspect, in which the detection unit individually causes the plurality of light-emitting elements to emit light, and calculates the amount of light received by light-receiving elements other than the light-receiving elements corresponding to the light-emitting elements that emitted light, using the amount of light received as a correction amount.

[0018] The detection device according to an eleventh aspect is a detection device according to any one of the first to tenth aspects, wherein the light-emitting element array is capable of emitting light for each of a plurality of light-emitting sections, each of which includes at least two light-emitting elements, and the detection unit controls the light emission for each of the plurality of light-emitting sections.

[0019] A detection device according to a twelfth aspect is the detection device according to any one of the first to eleventh aspects, wherein the detection section detects the distance to the object to be detected by time-of-flight.

[0020] The detection device of the thirteenth aspect comprises a light-emitting element array having a plurality of light-emitting elements, a light-receiving element array having a plurality of light-receiving elements that receive reflected light of light emitted from the light-emitting element array toward the object to be detected, a drive unit that selectively drives a plurality of the light-emitting element arrays, and a detection unit that causes the light-emitting elements to emit light and causes the light-emitting elements corresponding to the light-receiving elements that receive an amount of light less than a predetermined threshold out of the amount of light received by the light-receiving elements to emit light, thereby detecting the object to be detected.

[0021] A detection device according to a fourteenth aspect includes a processor that controls the emission of light from a plurality of light-emitting elements included in a light-emitting element array, and if there is a light-receiving element among a plurality of light-receiving elements included in a light-receiving element array that receives reflected light of light emitted from the light-emitting element array toward the object to be detected that receives light other than direct light that is directly reflected from the object to be detected onto the light-receiving element, the processor causes light-emitting elements other than the light-emitting element that irradiated the light other than direct light onto the light-receiving element to emit light, and detects the object to be detected from the amount of light received by the light-receiving element.

[0022] A detection program according to a fifteenth aspect is a detection program for causing a computer to execute a process of controlling the emission of a plurality of light-emitting elements included in an array of light-emitting elements, and if there is a light-receiving element among a plurality of light-receiving elements included in an array of light-receiving elements that receives reflected light of light emitted from the array of light-emitting elements toward the object to be detected and that receives light other than direct light that is directly reflected from the object to be detected toward the light-receiving element, causing light-emitting elements other than the light-emitting element that irradiated the light other than direct light to the light-receiving element to emit light, thereby detecting the object to be detected from the amount of light received by the light-receiving element.

[0023] The optical device according to the sixteenth aspect includes a light-emitting element array having a plurality of light-emitting elements, a light-receiving element array having a plurality of light-receiving elements, and a detection unit according to any one of the first to thirteenth aspects. [Effects of the Invention]

[0024] According to the first and thirteenth to sixteenth aspects, when detecting a detection target by detecting reflected light of light emitted from a light-emitting element array having a plurality of light-emitting elements toward the detection target, the influence of light other than direct light can be suppressed compared to when light other than direct light that is directly incident on and reflected from the detection target is not taken into consideration.

[0025] According to the second aspect, it is possible to prevent the amount of received light from becoming saturated, compared to when all the light-emitting elements are made to emit light regardless of the amount of received light.

[0026] According to the third aspect, it is possible to prevent the amount of received light from becoming saturated, compared to when all the light-emitting elements are caused to emit light the same number of times.

[0027] According to the fourth aspect, the processing time can be reduced compared to when sequentially emitting light from a light-emitting element corresponding to a light-receiving element receiving an amount of light less than the threshold and emitting light from a light-emitting element corresponding to a light-receiving element receiving an amount of light equal to or greater than the threshold.

[0028] According to the fifth aspect, the influence of multipath can be avoided compared to when all the light emitting elements are made to emit light.

[0029] According to the sixth aspect, it is possible to avoid the influence of multipath due to walls and the like.

[0030] According to the seventh aspect, it is possible to avoid the influence of mutual interference of light.

[0031] According to the eighth aspect, the influence of mutual interference of light can be further avoided.

[0032] According to the ninth aspect, the influence of indirect light can be suppressed compared to when all the light-emitting elements are made to emit light.

[0033] According to the tenth aspect, it is possible to prevent the control of light emission of the light-emitting element from becoming complicated.

[0034] According to the eleventh aspect, it is possible to prevent the control of the light-emitting elements from becoming complicated, compared to when light emission is controlled for each light-emitting element.

[0035] According to the twelfth aspect, the three-dimensional shape of the detection object can be identified. [Brief explanation of the drawings]

[0036] [Figure 1] 1 is a schematic diagram illustrating the configuration of a measurement device according to a first embodiment. [Figure 2] FIG. 2 is a block diagram showing the main configuration of an electrical system of the measurement device. [Figure 3] FIG. [Figure 4] FIG. 10 is a diagram for explaining light-emitting sections. [Figure 5] FIG. 2 is a circuit diagram of the measurement device. [Figure 6] FIG. 2 is a plan view of a 3D sensor. [Figure 7] 6 is a flowchart showing an example of the processing flow of a measurement program according to the first embodiment. [Figure 8] FIG. 2 is a plan view of a 3D sensor. [Figure 9]FIG. 10 is a diagram illustrating multipath. [Figure 10] FIG. 10 is a diagram illustrating multipath. [Figure 11] 10 is a flowchart showing an example of the processing flow of a measurement program according to the second embodiment. [Figure 12] 11 is a flowchart showing an example of the processing flow of a measurement program according to the third embodiment. [Figure 13] 10 is a flowchart showing an example of the processing flow of a measurement program according to the fourth embodiment. [Figure 14] 13 is a flowchart showing an example of the processing flow of a measurement program according to the fifth embodiment. [Figure 15] 13 is a flowchart showing an example of the processing flow of a measurement program according to the sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0037] Hereinafter, an example of an embodiment of the disclosed technology will be described in detail with reference to the drawings.

[0038] First Embodiment

[0039] Among measurement devices that measure the three-dimensional shape of a measurement target, there are devices that measure the three-dimensional shape based on the so-called ToF (Time of Flight) method, which relies on the time of flight of light. The ToF method measures the time from when light is emitted from a light source of the measurement device to when the irradiated light is reflected by the measurement target and received by a three-dimensional sensor (hereinafter referred to as a 3D sensor) of the measurement device, and determines the three-dimensional shape by measuring the distance to the measurement target. Note that an object whose three-dimensional shape is being measured is referred to as a measurement target. A measurement target is an example of an object to be detected. Measuring a three-dimensional shape is sometimes referred to as three-dimensional measurement, 3D measurement, or 3D sensing.

[0040] The ToF method includes a direct method and a phase difference method (indirect method). The direct method is a method in which pulsed light that is emitted for a very short time is irradiated onto the object to be measured, and the time it takes for the light to return is measured. The phase difference method is a method in which pulsed light is periodically flashed, and the time delay when multiple pulsed light beams travel back and forth between the object to be measured and the object is detected as a phase difference. In this embodiment, a case in which a three-dimensional shape is measured using the phase difference method will be described.

[0041] Such measurement devices are installed in portable information processing devices and the like, and are used for, for example, facial authentication of users attempting to access the devices. Conventionally, methods for authenticating users using passwords, fingerprints, irises, etc. have been used in portable information processing devices. In recent years, there has been a demand for authentication methods with higher security. Therefore, portable information processing devices have begun to be equipped with measurement devices that measure three-dimensional shapes. That is, a three-dimensional image of the face of the accessing user is acquired, and it is determined whether or not the access is permitted. Only when the user is authenticated as being authorized to access, is the device (portable information processing device) permitted to be used.

[0042] Such a measuring device is also applicable to cases where the three-dimensional shape of an object to be measured is continuously measured, such as in augmented reality (AR).

[0043] The configurations, functions, methods, etc. described in the present embodiment below can be applied not only to face authentication and augmented reality, but also to measuring the three-dimensional shape of other measurement objects.

[0044] (Measuring device 1)

[0045] FIG. 1 is a block diagram illustrating an example of the configuration of a measurement apparatus 1 that measures a three-dimensional shape.

[0046] The measurement device 1 includes an optical device 3 and a control unit 8. The control unit 8 controls the optical device 3. The control unit 8 includes a three-dimensional shape specifying unit 81 that specifies the three-dimensional shape of the object to be measured. The measurement device 1 is an example of a detection device. The control unit 8 is an example of a detection unit.

[0047] Fig. 2 is a block diagram showing the hardware configuration of the control unit 8. As shown in Fig. 2, the control unit 8 includes a controller 12. The controller 12 includes a central processing unit (CPU) 12A, a read-only memory (ROM) 12B, a random access memory (RAM) 12C, and an input / output interface (I / O) 12D. The CPU 12A, the ROM 12B, the RAM 12C, and the I / O 12D are connected to each other via a system bus 12E. The system bus 12E includes a control bus, an address bus, and a data bus.

[0048] Furthermore, a communication unit 14 and a storage unit 16 are connected to the I / O 12D.

[0049] The communication unit 14 is an interface for performing data communication with an external device.

[0050] The storage unit 16 is configured with a non-volatile rewritable memory such as a flash ROM, and stores a measurement program 16A and a partition correspondence table 16B, which will be described later. The CPU 12A loads the measurement program 16A stored in the storage unit 16 into the RAM 12C and executes it, thereby configuring a three-dimensional shape specification unit 81 and specifying the three-dimensional shape of the object to be measured. The measurement program 16A is an example of a detection program.

[0051] The optical device 3 includes a light-emitting device 4 and a 3D sensor 5. The light-emitting device 4 includes a wiring substrate 10, a heat dissipation base 100, a light source 20, a light diffusing member 30, a drive unit 50, a holding unit 60, and capacitors 70A and 70B. The light-emitting device 4 may further include passive elements such as a resistive element 6 and a capacitor 7 to operate the drive unit 50. Here, two resistive elements 6 and two capacitors 7 are included. Although two capacitors 70A and 70B are shown, one may be included. When the capacitors 70A and 70B are not distinguished, they are referred to as capacitors 70. Furthermore, the resistive element 6 and the capacitor 7 may each be one or more. Here, electrical components such as the 3D sensor 5, the resistive element 6, and the capacitor 7, other than the light source 20, the drive unit 50, and the capacitor 70, may be referred to as circuit components without distinction. Capacitors are sometimes referred to as condensers. The 3D sensor 5 is an example of a light-receiving element array.

[0052] The heat dissipation base 100, the drive unit 50, the resistive element 6, and the capacitor 7 of the light emitting device 4 are provided on the surface of the wiring substrate 10. Although the 3D sensor 5 is not provided on the surface of the wiring substrate 10 in FIG. 1, it may be provided on the surface of the wiring substrate 10.

[0053] The light source 20, the capacitors 70A and 70B, and the holder 60 are provided on the surface of the heat dissipation base material 100. The light diffusing member 30 is provided on the holder 60. Here, the outer shape of the heat dissipation base material 100 and the outer shape of the light diffusing member 30 are assumed to be the same. Here, the term "surface" refers to the front side of the paper in FIG. 1. More specifically, in the wiring board 10, the side on which the heat dissipation base material 100 is provided is referred to as the surface, front side, or front surface side. In addition, in the heat dissipation base material 100, the side on which the light source 20 is provided is referred to as the surface, front side, or front surface side.

[0054] The light source 20 is configured as a light-emitting element array in which a plurality of light-emitting elements are arranged two-dimensionally (see FIG. 3 described later). One example of the light-emitting element is a vertical-cavity surface-emitting laser (VCSEL). In the following description, the light-emitting element is described as a vertical-cavity surface-emitting laser (VCSEL). The vertical-cavity surface-emitting laser (VCSEL) will be referred to as VCSEL. Since the light source 20 is provided on the surface of the heat-dissipating base 100, the light source 20 emits light perpendicular to the surface of the heat-dissipating base 100, in a direction away from the heat-dissipating base 100. In other words, the light-emitting element array is a surface-emitting laser array. Note that the plurality of light-emitting elements in the light source 20 are arranged two-dimensionally, and the surface of the light source 20 that emits light may be referred to as an emission surface.

[0055] Light emitted from the light source 20 is incident on the light diffusing member 30. The light diffusing member 30 then diffuses the incident light and emits it. The light diffusing member 30 is provided to cover the light source 20 and the capacitors 70A and 70B. That is, the light diffusing member 30 is provided at a predetermined distance from the light source 20 and the capacitors 70A and 70B provided on the heat dissipation base material 100 by a holding portion 60 provided on the surface of the heat dissipation base material 100. Therefore, the light emitted from the light source 20 is diffused by the light diffusing member 30 and irradiated onto the object to be measured. That is, the light emitted from the light source 20 is diffused by the light diffusing member 30 and irradiated over a wider range than when the light diffusing member 30 is not provided.

[0056] When performing three-dimensional measurement using the ToF method, the light source 20 is required to emit pulsed light (hereinafter referred to as emitted light pulses) at, for example, 100 MHz or higher and with a rise time of 1 ns or less, using the driving unit 50. In the case of facial recognition, for example, the distance over which the light is irradiated is approximately 10 cm to 1 m. The range over which the light is irradiated is approximately 1 m square. The distance over which the light is irradiated is referred to as the measurement distance, and the range over which the light is irradiated is referred to as the irradiation range or measurement range. A surface virtually located within the irradiation range or measurement range is referred to as the irradiation surface. In cases other than facial recognition, the measurement distance to the object to be measured and the irradiation range for the object to be measured may be other than those described above.

[0057] The 3D sensor 5 includes a plurality of light receiving elements, for example, 640×480 light receiving elements, and outputs a signal corresponding to the time from when light is emitted from the light source 20 to when the light is received by the 3D sensor 5.

[0058] For example, each light-receiving element of the 3D sensor 5 receives pulsed light (hereinafter referred to as a received light pulse) reflected from the object to be measured in response to an emitted light pulse from the light source 20, and accumulates a charge corresponding to the time it takes for the light to be received. The 3D sensor 5 is configured as a CMOS device, with each light-receiving element having two gates and a corresponding charge storage section. Alternately applying pulses to the two gates transfers generated photoelectrons to one of the two charge storage sections at high speed. Charges corresponding to the phase difference between the emitted light pulse and the received light pulse are accumulated in the two charge storage sections. The 3D sensor 5 then outputs a digital value corresponding to the phase difference between the emitted light pulse and the received light pulse as a signal for each light-receiving element via an AD converter. That is, the 3D sensor 5 outputs a signal corresponding to the time from when light is emitted from the light source 20 to when the light is received by the 3D sensor 5. In other words, the 3D sensor 5 acquires a signal corresponding to the three-dimensional shape of the object to be measured. The AD converter may be provided in the 3D sensor 5 or may be provided outside the 3D sensor 5.

[0059] As described above, the measurement device 1 diffuses the light emitted by the light source 20 and irradiates the object to be measured, and receives the light reflected from the object to be measured by the 3D sensor 5. In this way, the measurement device 1 measures the three-dimensional shape of the object to be measured.

[0060] First, the light source 20, the light diffusing member 30, the driving section 50, and the capacitors 70A and 70B that constitute the light emitting device 4 will be described.

[0061] (Configuration of light source 20)

[0062] 3 is a plan view of light source 20. Light source 20 is configured by arranging multiple VCSELs in a two-dimensional array. In other words, light source 20 is configured as a light-emitting element array using VCSELs as light-emitting elements. The rightward direction on the paper surface is defined as the x-direction, and the upward direction on the paper surface is defined as the y-direction.

[0063] The direction perpendicular to the x and y directions is defined as the z direction. The front surface of light source 20 refers to the front side of the paper, i.e., the surface on the +z direction side, and the back surface of light source 20 refers to the back side of the paper, i.e., the surface on the -z direction side. The plan view of light source 20 is a view of light source 20 as seen from the front surface side.

[0064] More specifically, in the light source 20, the side on which an epitaxial layer that functions as a light emitting layer (active region 206 described later) is formed is referred to as the surface, front side, or front surface side of the light source 20.

[0065] A VCSEL is a light-emitting element that has an active region serving as a light-emitting region between a lower multilayer reflector and an upper multilayer reflector stacked on a semiconductor substrate 200, and emits laser light perpendicular to the surface. For this reason, VCSELs can be more easily formed into a two-dimensional array than edge-emitting lasers. The number of VCSELs included in the light source 20 is, for example, 100 to 1000. The multiple VCSELs are connected in parallel and driven in parallel. The number of VCSELs listed above is an example, and may be set according to the measurement distance and irradiation range.

[0066] 4, the light source 20 is divided into a plurality of light-emitting sections 24, and each light-emitting section is driven individually. In the example of FIG. 4, as shown by the dashed lines, there are 12 light-emitting sections 24 (4×3). 11 ~24 34 However, the number of light-emitting sections is not limited to this. When no particular distinction is made between the light-emitting sections, they are simply referred to as light-emitting sections 24. In the example of Fig. 4, one light-emitting section 24 includes 16 VCSELs, but the number of VCSELs included in one light-emitting section 24 is not limited to this, and it is sufficient that one or more VCSELs are included.

[0067] An anode electrode 218 (see FIG. 5) common to the multiple VCSELs is provided on the front surface of the light source 20. A cathode electrode 214 (see FIG. 5) is provided on the back surface of the light source 20. In other words, the multiple VCSELs are connected in parallel. By driving the multiple VCSELs connected in parallel, light with a higher intensity is emitted compared to when the VCSELs are driven individually.

[0068] Here, the shape of light source 20 when viewed from the front side (referred to as a planar shape, the same applies below) is rectangular. The side surface on the -y direction side is referred to as side surface 21A, the side surface on the +y direction side is referred to as side surface 21B, the side surface on the -x direction side is referred to as side surface 22A, and the side surface on the +x direction side is referred to as side surface 22B. Side surface 21A and side surface 21B face each other. Side surface 22A and side surface 22B connect side surface 21A and side surface 21B, respectively, and face each other.

[0069] The center of the planar shape of the light source 20, that is, the center in the x and y directions, is defined as a center Ov.

[0070] (Driver 50 and capacitors 70A and 70B)

[0071] If it is desired to drive the light source 20 at higher speed, low-side driving is preferable. Low-side driving refers to a configuration in which a driving element such as a MOS transistor is located downstream of the current path of a driving target such as a VCSEL. Conversely, a configuration in which a driving element is located upstream is called high-side driving.

[0072] FIG. 5 is a diagram showing an example of an equivalent circuit when the light source 20 is driven by low-side driving. FIG. 5 shows the VCSEL of the light source 20, the driving unit 50, the capacitors 70A and 70B, and the power supply 82. The power supply 82 is provided in the control unit 8 shown in FIG. 1. The power supply 82 generates a DC voltage with the positive side serving as a power supply potential and the negative side serving as a reference potential. The power supply potential is supplied to a power supply line 83, and the reference potential is supplied to a reference line 84. The reference potential may be a ground potential (sometimes referred to as GND, and represented as [G] in FIG. 5).

[0073] As described above, the light source 20 is configured by connecting a plurality of VCSELs in parallel. The anode electrode 218 of the VCSEL (see FIG. 3, denoted as [A] in FIG. 5) is connected to the power line 83.

[0074] As described above, the light source 20 is divided into a plurality of light-emitting sections 24, and the control unit 8 drives a VCSEL for each light-emitting section 24. Note that in Fig. 5, only one light-emitting section 24 is shown with three VCSELs, and the other VCSELs and light-emitting sections are not shown.

[0075] 5, a switch element SW is provided between each VCSEL and a power supply line 83, and each switch element SW is simultaneously turned on and off in response to a command from the control unit 8. As a result, the VCSELs included in one light-emitting section 24 are controlled to emit light or not emit light at the same timing.

[0076] The driving unit 50 includes an n-channel MOS transistor 51 and a signal generating circuit 52 that turns the MOS transistor 51 on and off. The drain (denoted as [D] in FIG. 5) of the MOS transistor 51 is connected to the cathode electrode 214 of the VCSEL (see FIG. 3; denoted as [K] in FIG. 5). The source (denoted as [S] in FIG. 5) of the MOS transistor 51 is connected to a reference line 84. The gate of the MOS transistor 51 is connected to the signal generating circuit 52. In other words, the VCSEL and the MOS transistor 51 of the driving unit 50 are connected in series between a power supply line 83 and a reference line 84. Under the control of the control unit 8, the signal generating circuit 52 generates an "H level" signal that turns the MOS transistor 51 on and an "L level" signal that turns the MOS transistor 51 off.

[0077] One terminal of each of the capacitors 70A and 70B is connected to a power supply line 83, and the other terminal is connected to a reference line 84. Here, when there are multiple capacitors 70, the multiple capacitors 70 are connected in parallel. That is, in FIG. 5, the capacitors 70 are two capacitors 70A and 70B. The capacitors 70 are, for example, electrolytic capacitors or ceramic capacitors.

[0078] Next, a method for driving the light source 20, which is low-side driving, will be described.

[0079] First, the control unit 8 turns on the switch element SW of the light-emitting section 24 in which the VCSEL is desired to emit light, and turns off the switch element SW of the light-emitting section 24 in which the VCSEL is not desired to emit light.

[0080] The following describes how the VCSEL included in the light-emitting section 24 is driven when the switch element SW is turned on.

[0081] First, assume that the signal generated by the signal generating circuit 52 in the driver 50 is at "L level." In this case, the MOS transistor 51 is in the off state. In other words, no current flows between the source ([S] in FIG. 5) and drain ([D] in FIG. 5) of the MOS transistor 51. Therefore, no current flows through the VCSEL connected in series with the MOS transistor 51. In other words, the VCSEL does not emit light.

[0082] At this time, capacitors 70A and 70B are connected to a power supply 82, and one terminal of capacitors 70A and 70B connected to a power supply line 83 is at the power supply potential, and the other terminal connected to a reference line 84 is at the reference potential. Therefore, a current flows (charge is supplied) from the power supply 82 to charge capacitors 70A and 70B.

[0083] Next, when the signal generated by the signal generating circuit 52 in the driver 50 goes to "H level," the MOS transistor 51 transitions from an OFF state to an ON state. This forms a closed loop with the capacitors 70A and 70B and the series-connected MOS transistor 51 and VCSEL, and the charge stored in the capacitors 70A and 70B is supplied to the series-connected MOS transistor 51 and VCSEL. This means that a drive current flows through the VCSEL, causing it to emit light. This closed loop is the drive circuit that drives the light source 20.

[0084] Then, when the signal generated by the signal generating circuit 52 in the driving unit 50 goes low again, the MOS transistor 51 transitions from the on state to the off state. As a result, the closed loop (driving circuit) between the capacitors 70A, 70B and the series-connected MOS transistor 51 and VCSEL becomes an open loop, and no driving current flows to the VCSEL. This causes the VCSEL to stop emitting light. Then, the capacitors 70A, 70B are charged by the supply of electric charge from the power supply 82.

[0085] As described above, each time the signal output by the signal generating circuit 52 transitions between "H level" and "L level," the MOS transistor 51 repeatedly turns on and off, causing the VCSEL to repeatedly emit and not emit light. The repeated on and off of the MOS transistor 51 is sometimes called switching.

[0086] Incidentally, if the 3D sensor 5 can receive only the light that is emitted from the light source 20 and directly incident on the object to be measured and reflected, it will be possible to measure the distance to the object to be measured with high accuracy.

[0087] However, in reality, the 3D sensor 5 is equipped with a lens (not shown), and there is a problem of lens flare in which extraneous light that is multiple-reflected by this lens is received by a light-receiving element that should not receive the light. Note that, hereinafter, light that is directly incident on the object to be measured and reflected and directly received by a light-receiving element is referred to as direct light. Furthermore, extraneous light other than direct light is referred to as indirect light.

[0088] Lens flare can cause a light receiving element that receives not only direct light but also indirect light to receive more light than expected, resulting in saturation. Also, if there is an obstacle, such as a user's finger, between the measurement device 1 and the object to be measured, the amount of light received may exceed the expected amount due to unnecessary indirect light reflected by the obstacle.

[0089] Therefore, in this embodiment, the 3D sensor 5 includes a plurality of light receiving elements PD that receive reflected light emitted from the light source 20 toward the object to be measured. The light receiving elements PD directly receive light that is directly incident on the object and reflected from it. The distance to the object is measured from the amount of direct light received by the light receiving elements PD. Specifically, the VCSELs corresponding to the light receiving elements PD that receive an amount of light less than a predetermined threshold are caused to emit light to measure the distance to the object. In other words, the VCSELs corresponding to the light receiving elements PD that receive an amount of light equal to or greater than a predetermined threshold are not caused to emit light. The series of processes from emitting light from the light source 20 to measuring the distance to the object to be measured is sometimes referred to as integration.

[0090] In this embodiment, as shown in Fig. 6, the 3D sensor 5 is divided into a plurality of light receiving sections 26. Each light receiving section 26 includes one or more light receiving elements PD. In the example of Fig. 6, one light receiving section 26 includes 16 light receiving elements PD, but the number of light receiving elements PD is not limited to this. For convenience of explanation, in the example of Fig. 6, the 3D sensor 5 is divided into 4 x 3 light receiving sections 26, similar to the light emitting section 24. 11 ~26 34 However, the number of light-receiving sections may be different from that of the light-emitting sections 24. When the light-receiving sections are not particularly distinguished, they are simply referred to as light-receiving sections 26.

[0091] In this embodiment, it is assumed that a light-receiving section 26 to which a light-receiving element PD that receives direct light belongs when all the VCSELs belonging to the light-emitting section 24 are made to emit light is specified in advance for each light-emitting section 24. The correspondence between the light-emitting section 24 and the light-receiving section 26 is stored in advance in the storage unit 16 as a section correspondence table 16B (see FIG. 2).

[0092] The section correspondence table 16B is calculated from the amount of light received by each light receiving section 26 when each light emitting section 24 is individually illuminated with light toward a predetermined object to be measured in a state where there are no obstacles or the like.

[0093] The light-emitting sections 24 and the light-receiving sections 26 may correspond to each other in one-to-one, many-to-one, one-to-many, or many-to-many relationships, but in this embodiment, for the sake of convenience, they are assumed to correspond to each other in one-to-one relationship.

[0094] Next, the operation of the measurement device 1 according to this embodiment will be described. Fig. 7 is a flowchart showing the flow of measurement processing executed by the control unit 8 of the measurement device 1 according to this embodiment. The measurement processing shown in Fig. 7 is executed by the CPU 12A reading the measurement program 16A stored in the storage unit 16.

[0095] In step S100, the MOS transistors 51 of the driving unit 50 are turned on and all switch elements SW are turned on so that the VCSELs in all light-emitting sections 24 of the light source 20 emit light. This causes all the VCSELs to emit light.

[0096] In step S102, the amount of light received (amount of charge) by the light receiving elements of all the light receiving sections 26 is acquired from the 3D sensor 5.

[0097] In step S104, it is determined whether or not there is a light receiving element whose received light amount is equal to or greater than a predetermined threshold. The threshold is set to a value that allows determination that indirect light as well as direct light is being received and the received light amount is saturated. If there is a light receiving element whose received light amount is equal to or greater than the predetermined threshold, the process proceeds to step S106. On the other hand, if there is no light receiving element whose received light amount is equal to or greater than the predetermined threshold, the process proceeds to step S110.

[0098] In step S106, the section correspondence table 16B is referenced to identify the light-emitting section 24 corresponding to the light-receiving section 26 to which the light-receiving element with the received light amount equal to or greater than the threshold belongs. Then, the light-emitting section 24 other than the identified light-emitting section 24 is designated as the first light-emitting section 24. The VCSELs belonging to the first light-emitting section 24 are caused to emit light a predetermined number of times, and the amount of light received by the light-receiving elements belonging to the light-receiving section 26 corresponding to the first light-emitting section 24 is acquired from the 3D sensor 5. The distance to the object is measured using the phase difference method described above. That is, the VCSELs belonging to the first light-emitting section 24 corresponding to the light-receiving section 26 to which the light-receiving element with the received light amount less than the threshold belong are caused to emit light, thereby measuring the distance to the object. In this way, the VCSELs belonging to the first light-emitting section 24 corresponding to the light-receiving section 26 with the least influence of indirect light are caused to emit light, thereby measuring the distance to the object. Note that the distance to the object may also be measured by acquiring only the amount of light received by the light-receiving elements belonging to the light-receiving section 26 corresponding to the first light-emitting section 24.

[0099] In step S108, the VCSELs belonging to the second light-emitting sections 24 other than the first light-emitting section 24 are caused to emit light, and the amount of light received by the light-receiving elements belonging to the light-receiving sections 26 corresponding to the second light-emitting sections 24 that have been caused to emit light is obtained from the 3D sensor 5 to measure the distance to the object. At this time, the VCSELs belonging to the second light-emitting sections 24 are caused to emit light a number N2 that is smaller than the number N1 of times the VCSELs of the first light-emitting sections 24 were caused to emit light in step S106. Note that the number N2 is set to the number of times at which the amount of light received by the light-receiving elements falls below a threshold. This prevents the amount of light received by the light-receiving elements from exceeding the threshold.

[0100] In step S110, since there is no light receiving element for which the amount of received light is equal to or greater than the threshold, the distance to the object to be measured is measured from the amount of received light of all the light receiving elements acquired in step S102.

[0101] In this manner, in this embodiment, the light-emitting section corresponding to the light-receiving section 26 containing the light-receiving elements whose received light amount is less than the predetermined threshold is the first light-emitting section 24, and the light-emitting section corresponding to the light-receiving section 26 containing the light-receiving elements whose received light amount is equal to or greater than the predetermined threshold is the second light-emitting section 24. The second light-emitting section 24 is then illuminated a reduced number of times.

[0102] For example, as shown in FIG. 22 , 26 23 , 26 31 , 26 34 In this case, it is assumed that the amount of light received by at least some of the light receiving elements belonging to the light receiving section 26 is equal to or greater than the threshold value. 22 , 26 23 , 26 31 , 26 34 24 light-emitting sections corresponding to 22 ,twenty four 23 ,twenty four 31 ,twenty four 34 is set as the second light-emitting section 24, and the other light-emitting sections 24 corresponding to the light-receiving sections 26 are set as the first light-emitting sections 24.

[0103] 7, step S106 is executed first, followed by step S108, but step S106 and step S108 may be executed in parallel. That is, the first light-emitting section 24 and the second light-emitting section 24 are illuminated in parallel. This reduces the processing time.

[0104] Second Embodiment

[0105] Next, a second embodiment will be described. Note that the same parts as those in the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted.

[0106] The configuration of the measurement device 1 is the same as that of the first embodiment, so a description thereof will be omitted.

[0107] The lens flare described in the first embodiment is not the only problem that can arise when irradiating a measurement object with light from the light source 20 and receiving the reflected light to measure the distance to the measurement object. For example, as shown in Fig. 9, the light emitted from the light source 20 is not just direct light L1 that is directly incident on and reflected from the measurement object 28. For example, there is the problem of multipath light, where light is reflected by an obstacle such as a wall 32, travels multiple paths, and is received by the 3D sensor 5 as multipath light L2.

[0108] Multipath causes the light receiving element to receive not only direct light but also indirect light that should not be received, which can affect the accuracy of the measured distance.

[0109] Therefore, in this embodiment, the second light-emitting section 24 corresponding to the light-receiving section 26 containing the light-receiving element that received indirect light that should not have been received is not made to emit light, and the VCSELs belonging to the first light-emitting section 24 other than the second light-emitting section 24 are made to emit light to measure the distance to the object to be measured. As a result, as shown in Fig. 10, the distance to the object to be measured is measured while suppressing the influence of the multipath light L2.

[0110] The operation of this embodiment will be described below. Fig. 11 is a flowchart showing the flow of measurement processing executed by the control unit 8 of the measurement device 1 according to this embodiment.

[0111] In step S200, one unlight-emitting section 24 is caused to emit light. That is, the MOS transistor 51 of the drive unit 50 is turned on and the switch element SW of the unlight-emitting section 24 is turned on so that the VCSEL in the unlight-emitting section 24 emits light. As a result, the VCSEL in the one light-emitting section 24 emits light, and the VCSELs in the other light-emitting sections 24 do not emit light.

[0112] In step S202, the amount of light received by the light receiving elements belonging to all the light receiving sections 26 is acquired from the 3D sensor 5.

[0113] In step S204, the section correspondence table 16B is referenced to identify the first light-receiving section 26 corresponding to the light-emitting section 24 that was illuminated in step S200. Then, based on the light-receiving amount of the light-receiving elements belonging to all the light-receiving sections 26 acquired in step S202, it is determined whether light was received in a second light-receiving section 26 other than the first light-receiving section 26.

[0114] If light is received in the second light-receiving section 26, the process proceeds to step S206, and if light is not received in the second light-receiving section 26, the process proceeds to step S208.

[0115] In step S206, the light-emitting section 24 that was illuminated in step S200 is set as the second light-emitting section 24.

[0116] On the other hand, in step S208, the light-emitting section 24 that was illuminated in step S200 is set as the first light-emitting section 24.

[0117] In step S210, it is determined whether all light-emitting sections 24 have been illuminated, and if all light-emitting sections 24 have been illuminated, the process proceeds to step S212. On the other hand, if there are any unilluminated light-emitting sections 24, the process proceeds to step S200, where the unilluminated light-emitting sections 24 are illuminated and the same process as above is performed.

[0118] In step S212, only the first light-emitting section 24 set in step S208 is illuminated a predetermined number of times, the amount of light received by each light-receiving element is obtained from the 3D sensor 5, and the distance to the object to be measured is measured using the phase difference method described above.

[0119] In this way, in this embodiment, when light is received by a light receiving element belonging to a second light receiving section 26 other than the first light receiving section 26 corresponding to the light emitting section 24 that has been illuminated, the first light emitting section 24 other than the second light emitting section 24 corresponding to the second light receiving section 26 is illuminated to measure the distance to the object to be measured.

[0120] Third Embodiment

[0121] Next, a third embodiment will be described. Note that the same parts as those in the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted.

[0122] The configuration of the measurement device 1 is the same as that of the first embodiment, so a description thereof will be omitted.

[0123] The operation of this embodiment will be described below. Fig. 12 is a flowchart showing the flow of measurement processing executed by the control unit 8 of the measurement device 1 according to this embodiment.

[0124] 7, in step S300, the MOS transistors 51 of the driving unit 50 are turned on and all switch elements SW are turned on so that the VCSELs in all light-emitting sections 24 of the light source 20 emit light, thereby causing all the VCSELs to emit light.

[0125] In step S302, similar to step S102 in FIG. 7, the amount of light (amount of charge) received by the light receiving elements of all light receiving sections 26 is obtained from the 3D sensor 5, and the distance to the object to be measured is measured from the obtained amount of light.

[0126] In step S304, it is determined whether or not there is a light-receiving section 26 in which the distance measured in step S302 changes continuously. If there is a light-receiving section 26 in which the distance changes continuously, the process proceeds to step S306, and if there is no light-receiving section 26 in which the distance changes continuously, the process proceeds to step S308.

[0127] In step S306, the light-emitting section 24 corresponding to the light-receiving section 26 whose distance changes continuously is set as the second light-emitting section 24, and the other light-emitting sections are set as the first light-emitting section 24.

[0128] In step S308, all light-emitting sections 24 are set to the first light-emitting sections 24.

[0129] In step S310, the first light-emitting section 24 is caused to emit light, and the amount of light received by the light-receiving elements of all the light-receiving sections 26 is acquired from the 3D sensor 5, and the distance to the object to be measured is measured.

[0130] This prevents the light emitting section 24 from emitting light onto a wall or the like whose distance changes continuously, thereby avoiding the influence of multipath.

[0131] <Fourth embodiment>

[0132] Next, a fourth embodiment will be described. Note that the same parts as those in the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted.

[0133] The configuration of the measurement device 1 is the same as that of the first embodiment, so a description thereof will be omitted.

[0134] The operation of this embodiment will be described below. Fig. 13 is a flowchart showing the flow of measurement processing executed by the control unit 8 of the measurement device 1 according to this embodiment.

[0135] In step S400, similar to step S200 in FIG. 11, the light-emitting sections 24 that have not yet been illuminated are illuminated.

[0136] In step S402, similarly to step S202 in FIG. 11, the amounts of light received by the light receiving elements belonging to all the light receiving sections 26 are acquired from the 3D sensor 5, and the acquired amounts of light received are stored in the storage unit 16.

[0137] In step S404, it is determined whether all light-emitting sections 24 have been illuminated, and if all light-emitting sections 24 have been illuminated, the process proceeds to step S406. On the other hand, if there are any light-emitting sections 24 that have not yet been illuminated, the process proceeds to step S400, where the unilluminated light-emitting sections 24 are illuminated and the same process as above is performed. This results in a light-receiving amount map that shows the correspondence between the light-emitting sections 24 and the amount of light received by each light-receiving section 26 when that light-emitting section 24 is illuminated.

[0138] In step S406, the light emission order of the light-emitting sections 24 is set based on the light-receiving amount map. Specifically, the light emission order is set so that light is emitted for each light-emitting section 24 that does not cause mutual light interference. Here, mutual light interference refers to a situation in which, when multiple light-emitting sections 24 are simultaneously made to emit light, light is received by second light-receiving sections 26 other than the corresponding first light-receiving section 26, which adversely affects the accuracy of measurement.

[0139] For example, as shown in FIG. 8, the light receiving amount map is 22 24 light-emitting sections corresponding to 22 When the light receiving section 26 is illuminated, 22 The surrounding light receiving section 26 11 , 26 12 , 26 22 It is assumed that the received light amount map indicates that light is received even in the light receiving section 26. 23 24 light-emitting sections corresponding to 23 When the light receiving section 26 is illuminated, 23 The surrounding light receiving section 26 13 , 26 24 , 26 33 It is assumed that the received light amount map indicates that light is received even in the light receiving section 26. 31 24 light-emitting sections corresponding to 31 When the light receiving section 26 is illuminated, 31 The surrounding light receiving section 2621 , 26 22 , 26 32 It is assumed that the received light amount map indicates that light is received even in the light receiving section 26. 34 24 light-emitting sections corresponding to 34 When the light receiving section 26 is illuminated, 34 The surrounding light receiving section 26 23 , 26 24 , 26 33 However, it is assumed that the received light amount map shows that light was received.

[0140] In this case, the light receiving section 26 11 , 26 12 , 26 13 , 26 14 , 26 21 , 26 24 , 26 32 , 26 33 24 light-emitting sections corresponding to 11 ,twenty four 12 ,twenty four 13 ,twenty four 14 ,twenty four 21 ,twenty four 24 ,twenty four 32 ,twenty four 33 Similarly, even if the light receiving sections 26 are simultaneously illuminated, no mutual interference occurs. 22 , 26 23 24 light-emitting sections corresponding to 22 ,twenty four 23 Even if the light receiving sections 26 are simultaneously illuminated, no mutual interference occurs. 31 , 26 34 24 light-emitting sections corresponding to 31 ,twenty four 34 Even if they are emitted simultaneously, there is no mutual interference.

[0141] Therefore, in the example of FIG. 8, the light emitting section 24 11 ,twenty four 12 ,twenty four 13 ,twenty four 14 ,twenty four 21 ,twenty four 24 ,twenty four 32 ,twenty four 33 The second time, the light-emitting section 24 22 ,twenty four 23The third time, the light-emitting section 24 31 ,twenty four 34 The light emission order is set so that the light emission occurs simultaneously. It is preferable to set the light emission order so that the number of light emissions is minimized.

[0142] In step S408, the light-emitting sections 24 are illuminated in the light-emitting sequence set in step S406, and the distance to the object is measured.

[0143] In this way, based on the light reception amount map, light is emitted for each set of light emitting sections 24 in a combination that does not cause mutual interference of light.

[0144] Fifth Embodiment

[0145] Next, a fifth embodiment will be described. Note that the same parts as those in the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted.

[0146] The configuration of the measurement device 1 is the same as that of the first embodiment, so a description thereof will be omitted.

[0147] The operation of this embodiment will be described below. Fig. 14 is a flowchart showing the flow of measurement processing executed by the control unit 8 of the measurement device 1 according to this embodiment.

[0148] In step S500, similar to step S200 in FIG. 11, only one light-emitting section 24 that has not yet emitted light is made to emit light a predetermined number of times.

[0149] In step S502, the section correspondence table 16B is referenced to identify the light receiving section 26 corresponding to the light emitting section 24 illuminated in step S500, and the amount of light received by the light receiving element belonging to the identified light receiving section 26 is obtained from the 3D sensor 5.

[0150] In step S504, based on the amount of light received by each light receiving element obtained in step S504, the distance to the object to be measured in the light receiving section 26 corresponding to the light emitting section 24 that was illuminated in step S500 is measured using the phase difference method described above.

[0151] In step S506, it is determined whether all light-emitting sections 24 have been illuminated, and this routine ends if all light-emitting sections 24 have been illuminated. On the other hand, if there are any unilluminated light-emitting sections 24, the process proceeds to step S500, where the unilluminated light-emitting sections 24 are illuminated and the same process as above is performed.

[0152] In this manner, in this embodiment, the light-emitting sections 24 are caused to emit light one by one, and the process of measuring the distance to the object to be measured in the light-receiving section 26 corresponding to the light-emitting section 24 that has emitted light is performed individually.

[0153] Sixth Embodiment

[0154] Next, a sixth embodiment will be described. Note that the same parts as those in the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted.

[0155] The configuration of the measurement device 1 is the same as that of the first embodiment, so a description thereof will be omitted.

[0156] The operation of this embodiment will be described below. Fig. 15 is a flowchart showing the flow of measurement processing executed by the control unit 8 of the measurement device 1 according to this embodiment.

[0157] In step S600, similar to step S200 in FIG. 11, the light-emitting sections 24 that have not yet been illuminated are illuminated.

[0158] In step S602, similarly to step S202 in FIG. 11, the amounts of light received by the light receiving elements belonging to all the light receiving sections 26 are acquired from the 3D sensor 5.

[0159] In step S604, based on the amount of light received by the light receiving elements belonging to all light receiving sections 26 obtained in step S602, it is determined whether light was received in a second light receiving section 26 other than the first light receiving section 26 corresponding to the first light emitting section 24 that was illuminated in step S600.

[0160] If light is received in the second light-receiving section 26, the process proceeds to step S606, and if light is not received in the second light-receiving section 26, the process proceeds to step S608.

[0161] In step S606, the amount of light received by the light receiving elements of the second light receiving section 26 is stored in the storage unit 16 as a correction amount.

[0162] In step S608, it is determined whether all light-emitting sections 24 have been illuminated, and if all light-emitting sections 24 have been illuminated, the process proceeds to step S610. On the other hand, if there are any unilluminated light-emitting sections 24, the process proceeds to step S600, where the unilluminated light-emitting sections 24 are illuminated and the same process as above is performed.

[0163] In step S610, the VCSELs belonging to all the light-emitting sections 24 are caused to emit light.

[0164] In step S612, the amount of light received by the light receiving elements of all the light receiving sections 26 is acquired from the 3D sensor 5.

[0165] In step S614, for the light receiving elements in all light receiving sections 26 for which a correction amount has been stored in memory unit 16 in step S606, the amount of received light is corrected by subtracting the correction amount from the amount of received light. The corrected amount of received light is then used to measure the distance to the object to be measured. This avoids the effects of indirect light.

[0166] Although the embodiments have been described above, the technical scope of the present invention is not limited to the scope described in the above embodiments. Various modifications and improvements can be made to the above embodiments without departing from the gist of the invention, and such modifications and improvements are also included in the technical scope of the present invention.

[0167] Furthermore, the above-described embodiments do not limit the inventions described in the claims, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention. The above-described embodiments include inventions at various stages, and various inventions can be extracted by combining the multiple disclosed constituent elements. Even if some constituent elements are deleted from all of the constituent elements shown in the embodiments, as long as the effect is obtained, the configuration from which these constituent elements are deleted can be extracted as an invention.

[0168] For example, in each of the above embodiments, the three-dimensional shape of the object to be measured is determined by measuring the distance to the object to be measured, but it is also possible to simply detect whether the object to be measured is present within a predetermined distance.

[0169] 7 and 11 to 15 may be configured as a dedicated processor (for example, a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a programmable logic device, etc.) and incorporated into the optical device 3. In this case, the optical device 3 alone measures the distance to the object to be measured.

[0170] In the present embodiment, the measurement program 16A is installed in the storage unit 16, but the present invention is not limited to this. The measurement program 16A according to the present embodiment may be provided in a form recorded on a computer-readable storage medium. For example, the measurement program 16A according to the present embodiment may be provided in a form recorded on an optical disc such as a CD (Compact Disc)-ROM or a DVD (Digital Versatile Disc)-ROM, or in a form recorded on a semiconductor memory such as a USB (Universal Serial Bus) memory or a memory card. Furthermore, the measurement program 16A according to the present embodiment may be acquired from an external device via a communication line connected to the communication unit 14.

[0171] In the above embodiment, the term "processor" refers to a processor in a broad sense, and includes general-purpose processors (e.g., CPU: Central Processing Unit, etc.) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic device, etc.).

[0172] Furthermore, the operations of the processors in the above embodiments may not only be performed by a single processor, but may also be performed by multiple processors located at physically separate locations working together. Furthermore, the order of the operations of the processors is not limited to the order described in the above embodiments, and may be changed as appropriate. [Explanation of symbols]

[0173] 1. Measuring equipment 3 Optical equipment 4. Light-emitting device 5 3D sensors 6 Resistive elements 7 Capacitors 8 Control Unit 16A Measurement Program 16B Partition Correspondence Table 20 light source 24 Light-emitting section 26 Light receiving section 28 Measurement object 81 Three-dimensional shape identification part

Claims

1. a light-emitting element array including a plurality of light-emitting elements; a light-receiving element array including a plurality of light-receiving elements that receive reflected light of light emitted from the light-emitting element array toward the detection target; a driving unit that selectively drives the plurality of light-emitting element arrays; a detection unit that, when there is a light-receiving element that receives light other than direct light that is directly reflected from the detection object to the light-receiving element, detects the detection object from the amount of light received by the light-receiving element by making a light-emitting element other than the light-emitting element that irradiated the light other than the direct light onto the light-receiving element emit light; Equipped with The detection unit all the light-emitting elements are caused to emit light, and the object to be detected is detected by causing the light-emitting elements corresponding to the light-receiving elements with an amount of light received that is less than a predetermined threshold out of the amount of light received by all the light-receiving elements to emit light, and the object to be detected is detected by causing the light-emitting elements corresponding to the light-receiving elements with an amount of light received that is equal to or greater than the threshold to emit light a number of times that is less than the number of times that the light-emitting elements corresponding to the light-receiving elements with an amount of light received that is less than the threshold, and the light-emitting elements corresponding to the light-receiving elements with an amount of light received that is equal to or greater than the threshold, are caused to emit light in parallel; Detection device.

2. a light-emitting element array including a plurality of light-emitting elements; a light-receiving element array including a plurality of light-receiving elements that receive reflected light of light emitted from the light-emitting element array toward the detection target; a driving unit that selectively drives the plurality of light-emitting element arrays; a detection unit that, when there is a light-receiving element that receives light other than direct light that is directly reflected from the detection object to the light-receiving element, detects the detection object from the amount of light received by the light-receiving element by making a light-emitting element other than the light-emitting element that irradiated the light other than the direct light onto the light-receiving element emit light; Equipped with The detection unit causing all of the light-emitting elements to emit light, measuring the distance to the object to be detected from the amount of light received by all of the light-receiving elements, and causing light-emitting elements other than the light-emitting element that irradiated the light to the light-receiving element in the region where the distance changes continuously to emit light to detect the object to be detected. Detection device.

3. a light-emitting element array including a plurality of light-emitting elements; a light-receiving element array including a plurality of light-receiving elements that receive reflected light of light emitted from the light-emitting element array toward the detection target; a driving unit that selectively drives the plurality of light-emitting element arrays; a detection unit that, when there is a light-receiving element that receives light other than direct light that is directly reflected from the detection object to the light-receiving element, detects the detection object from the amount of light received by the light-receiving element by making a light-emitting element other than the light-emitting element that irradiated the light other than the direct light onto the light-receiving element emit light; Equipped with The detection unit The plurality of light-emitting elements are individually caused to emit light, and the object to be detected is detected by causing the plurality of light-emitting elements to emit light in a light-emitting order set from a light-receiving amount map of the amount of light received by the plurality of light-receiving elements, and causing each set of the light-emitting elements to emit light in a combination that does not cause mutual interference of light from the light-receiving amount map. Detection device.

4. The light emitting element array has a plurality of light emitting sections each including at least two light emitting elements. It is Noh, The detection unit controls light emission for each of the plurality of light-emitting sections. The detection device according to any one of claims 1 to 3.

5. The detection unit detects the distance to the detection target by time of flight. The detection device according to any one of claims 1 to 4.

6. On the computer, controlling light emission of a plurality of light-emitting elements included in the light-emitting element array toward the detection target; Among the plurality of light receiving elements included in the light receiving element array that receives reflected light of light emitted from the light emitting element array toward the detection object, if there is a light receiving element that receives light other than direct light that is directly reflected from the detection object to the light receiving element, the detection object is detected from the amount of light received by the light receiving element by making light emitting elements other than the light emitting element that irradiated the light other than direct light to the light receiving element emit light, All the light-emitting elements are caused to emit light, and the object to be detected is detected by causing the light-emitting elements corresponding to the light-receiving elements with an amount of light received that is less than a predetermined threshold out of the amount of light received by all the light-receiving elements to emit light, and the object to be detected is detected by causing the light-emitting elements corresponding to the light-receiving elements with an amount of light received that is equal to or greater than the threshold to emit light a number of times less than the number of times that the light-emitting elements corresponding to the light-receiving elements with an amount of light received that is less than the threshold, and the light-emitting elements corresponding to the light-receiving elements with an amount of light received that is equal to or greater than the threshold are caused to emit light in parallel. A detection program to execute the process.

7. On the computer, controlling light emission of a plurality of light-emitting elements included in the light-emitting element array toward the detection target; Among the plurality of light receiving elements included in the light receiving element array that receives reflected light of light emitted from the light emitting element array toward the detection object, if there is a light receiving element that receives light other than direct light that is directly reflected from the detection object to the light receiving element, the detection object is detected from the amount of light received by the light receiving element by making light emitting elements other than the light emitting element that irradiated the light other than direct light to the light receiving element emit light, All the light-emitting elements are made to emit light, the distance to the object to be detected is measured from the amount of light received by all the light-receiving elements, and the object to be detected is detected by making the light-emitting elements other than the light-emitting element that irradiated the light to the light-receiving elements in the area where the distance changes continuously emit light. A detection program to execute the process.

8. On the computer, controlling light emission of a plurality of light-emitting elements included in the light-emitting element array toward the detection target; Among the plurality of light receiving elements included in the light receiving element array that receives reflected light of light emitted from the light emitting element array toward the detection object, if there is a light receiving element that receives light other than direct light that is directly reflected from the detection object to the light receiving element, the detection object is detected from the amount of light received by the light receiving element by making light emitting elements other than the light emitting element that irradiated the light other than direct light to the light receiving element emit light, causing the plurality of light-emitting elements to emit light individually, and detecting the object to be detected by causing the plurality of light-emitting elements to emit light in a light-emitting order set from a light-receiving amount map of the amount of light received by the plurality of light-receiving elements of a light-receiving element array including the plurality of light-receiving elements; Based on the received light amount map, light is emitted for each set of the light emitting elements in a combination that does not cause mutual interference of light. A detection program to execute the process.

9. a light-emitting element array including a plurality of light-emitting elements; a light receiving element array including a plurality of light receiving elements; A detection unit according to any one of claims 1 to 5; An optical device comprising:

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