WO2024024745A1

WO2024024745A1 - Measuring device, light receiver, and light emitter

Info

Publication number: WO2024024745A1
Application number: PCT/JP2023/027061
Authority: WO
Inventors: 和也本橋; 喜吉村
Original assignee: 株式会社小糸製作所
Priority date: 2022-07-28
Filing date: 2023-07-24
Publication date: 2024-02-01

Abstract

A measuring device (100) comprises a light emitter, and a light receiver for receiving reflected light generated as a result of the emission of light toward a field of view by the light emitter. The light receiver includes a light receiving unit (16) and a transmission-type diffraction grating (151). The diffraction grating (151) is disposed such that first reflected light from a first field of view (51a) is incident on the light receiving unit (16) as diffracted light of a first order, and second reflected light from a separate second field of view (51b) aligned side-by-side with the first field of view (51a) is incident on the receiving unit (16) as diffracted light of a second order.

Description

Measuring device, receiver, and emitter

The present disclosure relates to a measuring device, a light receiver, and a light projector, and particularly relates to a technique for expanding the viewing range of a measuring device.

With the progress of AD (Autonomous Driving) and ADAS (Advanced Driver Assistance System), LiDAR ( Development/research on light detection and ranging is progressing. LiDAR includes a light projector that projects (irradiates) a laser beam onto a measurement target, and a light receiver that receives reflected light that is reflected by the laser light and returns to the measurement target. LiDAR provides information about a measurement target by measuring the distance to the measurement target based on the difference between the timing at which a light projector emits a laser beam and the timing at which a light receiver receives reflected light.

Patent Document 1 describes a LiDAR system configured for implementation in a vehicle. A LiDAR system includes multiple light emitters (such as Vertical Cavity Surface Emitting Laser (VCSEL) devices) that generate multiple optical beams. A LiDAR system has a first lens that focuses a plurality of optical beams into a focused optical beam having a beam waist, and a second lens that projects the focused optical beam onto a target area.

Japan Special Table No. 2020-527724

One type of LiDAR is Flash LiDAR, which uses a method in which a projector diffuses and irradiates laser light over a viewing range. Flash LiDAR does not include mechanical components such as motors or MEMS (Micro Electro Mechanical Systems), so it is attracting attention as a promising candidate for LiDAR in fields where durability is required, such as when used for automotive purposes. There is.

The field of view (FOV: viewing angle, beam profile, light distribution size) of the flash LiDAR receiver and emitter is determined by the size (area) of the light receiver and emitter and the optical system (receiving optical system, light emitter). It is determined by the focal length of the optical system). For this reason, when applying flash LiDAR to an individual system such as a ranging sensor for a vehicle, it is necessary to configure the system so that the field of view satisfies the specifications required by the system to which it is applied.

As a method of expanding the viewing range of LiDAR when mounted on a vehicle, for example, it is possible to install multiple LiDARs in parallel. However, in that case, the problem is an increase in the number of parts and cost. Furthermore, it is necessary to flexibly respond to needs such as, for example, wanting to improve the measurement accuracy of a specific visual field range (light projection range, visual field range) (such as wanting to improve long-distance visibility in the direction of travel during driving).

The present disclosure has been made in view of this background, and aims to provide a measuring device, a light projector, and a light receiver that can flexibly respond to specifications required by the system to which the system is applied.

One aspect of the present disclosure is a measuring device that includes a light projector and a light receiver that receives reflected light generated by the light projector projecting light toward a viewing range, and the light receiver includes a light receiving section and a light receiving section. , a transmission type diffraction grating, wherein the first reflected light from the first viewing range enters the light receiving section as a first order diffracted light, and the first reflected light from the first viewing range enters the light receiving section, The second reflected light from the second visual field lined up is incident on the light receiving section as second order diffracted light.

Another aspect of the present disclosure is a measuring device including a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range, and the projector includes a light emitting section. and a transmission type diffraction grating, the diffraction grating emits first-order diffracted light generated when light from the light emitting section passes through the diffraction grating toward a first viewing range. The second-order diffracted light generated when the light passes through the diffraction grating is emitted toward a second viewing range that is aligned with the first viewing range.

Another aspect of the present disclosure is a measurement device including a light projector and a light receiver that receives reflected light generated by the light projector projecting light toward a viewing range, and the light receiver receives light. and a transmissive optical element, the optical element having a first incident surface on which the first reflected light from the first viewing range is incident, and a transmissive optical element that is continuous with the first incident surface. a second incident surface on which a second reflected light from a second viewing range that is continuous with the first viewing range is incident; an exit surface for outputting light to a light receiving section, the first entrance surface, the second entrance surface, and the exit surface are all flat surfaces, and the second entrance surface is the first entrance surface. The first incident surface is inclined with respect to the first incident surface with a boundary line with the first incident surface as a fold line.

Another aspect of the present disclosure is a measuring device including a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range, and the projector includes a light emitting section. and a transmissive optical element, wherein the optical element includes an incident surface on which light from the light emitting section is incident, and a first surface that emits the light incident on the incident surface toward a first viewing range. and a second exit surface that outputs the light incident on the entrance surface toward a second viewing range, the entrance surface, the first exit surface, and the second exit surface. All of the output surfaces are flat surfaces, and the second output surface is inclined with respect to the first output surface with a boundary line with the second output surface as a fold.

Other problems disclosed in the present application and methods for solving the problems will be made clear by the detailed description section and the drawings.

According to the present disclosure, it is possible to provide a measuring device, a light projector, and a light receiver that can flexibly respond to specifications required by the system to which the system is applied.

FIG. 1 is a diagram showing a schematic configuration of a measuring device. FIG. 2A is a diagram illustrating the relationship between the light receiving section, the light receiving optical system, and the viewing range. FIG. 2B is a diagram illustrating the relationship between the light emitting unit, the projection optical system, and the viewing range. FIG. 3 is a diagram illustrating the relationship between the light receiver and the viewing range when a diffraction grating is used in the light receiving optical system according to the first embodiment. FIG. 4A is a diagram illustrating one aspect of the configuration of a measuring device that distinguishes from which viewing range the reflected light comes. FIG. 4B is a diagram showing one aspect of the arrangement of diffraction gratings. FIG. 5A is a diagram showing the relationship between the visual field range and the received light image in the configuration shown in FIG. 4A. FIG. 5B is a diagram showing the relationship between the viewing range and the received light image when the direction in which the slits of the diffraction grating are arranged is not rotated around the optical axis. FIG. 6 is a diagram illustrating parameters that determine the characteristics of the diffraction grating. FIG. 7 is a diagram illustrating the relationship between the projector and the viewing range when a diffraction grating is used in the projecting optical system according to the second embodiment. FIG. 8 is a diagram illustrating the relationship between the light receiver and the viewing range according to the third embodiment. FIG. 9A is an external perspective view of an optical element applied to the light receiver of FIG. 8. FIG. 9B is a side view of an optical element applied to the light receiver of FIG. 8. FIG. 10A is a diagram illustrating one aspect of the configuration of a measuring device that distinguishes from which viewing range the reflected light comes from. FIG. 10B is an external perspective view of the optical element used in the configuration of FIG. 10A. FIG. 11 is a diagram illustrating the relationship between the projector and the viewing range according to the fourth embodiment. FIG. 12A is an external perspective view of an optical element applied to the projector of FIG. 11. FIG. 12B is a side view of an optical element applied to the projector of FIG. 11.

Hereinafter, embodiments for carrying out the present disclosure will be described with reference to the drawings. In the following description, the same or similar configurations may be given the same reference numerals and redundant descriptions may be omitted. In addition, in the following description, if it is necessary to distinguish between configurations of the same type, an identifier (alphabet, etc.) may be added after the code that generically refers to the configuration.

FIG. 1 shows a schematic configuration (block diagram) of a measuring device 100 as an embodiment of the present disclosure. The measuring device 100 includes a light projector that projects (irradiates) light (irradiation light, light beam (laser light)) onto a measurement target, and a reflected light (return light) that reflects the projected light onto the measurement target and returns to the measurement target. ), and functions as a flash LiDAR (Flash Light Detection and Ranging). The measuring device 100 measures the difference between the timing at which the projector emits the projected light and the timing at which the receiver receives the reflected light (the flight time of the laser beam, hereinafter referred to as "TOF" (Time Of Flight)). to obtain information about the measurement target.

The measuring device 100 is installed, for example, in a vehicle in which AD (Autonomous Driving) or ADAS (Advanced Driver Assistance System) is installed. For example, the measuring device 100 assists in detecting people, other vehicles, and objects while the vehicle is running, as well as ensuring the safety of the vehicle driver and those around the vehicle. Provides other devices and users with various types of information useful for reducing damage to existing objects.

As shown in the figure, the illustrated measurement device 100 includes a light emitting section 11, a light projection control device 112, a current source 113, a light projection optical system 14, a light receiving optical system 15, a light receiving section 16, a TOF measurement device 117, and a calculation device. 150, and a communication I/F 160 (I/F:Interface). Of these, the light emitting section 11, the light projection control device 112, the current source 113, and the light projection optical system 14 constitute a light projector, and the light receiving optical system 15 and the light receiving section 16 constitute a light receiver.

The light emitting unit 11 constituting the floodlight includes one or more light emitting elements or one or more light emitting element arrays (for example, light emitting elements arranged in a linear (one-dimensional) or planar (two-dimensional) manner. ). Examples of the light emitting element include a laser diode, a surface emitting type laser emitting element (e.g., VCSEL (Vertical Cavity Surface Emitting Laser), hereinafter referred to as a "surface emitting element"), and a plurality of surface emitting elements that are one-dimensional. Alternatively, it is a surface emitting element array (for example, a VCSEL array) arranged two-dimensionally on a substrate (semiconductor substrate, ceramic substrate, etc.).

The light projection control device 112 generates a control signal for a current source 113 that supplies a drive current for a light emitting element constituting the light emitting unit 11 and inputs the control signal to the current source 113, so that the control signal is supplied from the current source 113 to the light emitting element. Controls the current (drive current). The light projection control device 112 inputs to the TOF measuring device 117 a signal indicating the timing at which the light emitting element emits light (the timing at which the projected light is emitted from the light emitting element; hereinafter referred to as "light projection timing"). The light projection control device 112 controls the light emitting elements to periodically and repeatedly turn on and off a current flowing through each of the light emitting elements, for example, thereby causing the light emitting elements to periodically and repeatedly emit light.

The current source 113 supplies a current to the light emitting element according to a control signal input from the light projection control device 112. The current source 113 supplies, for example, a periodic square wave current to the light emitting elements to turn on and off the current flowing through each of the light emitting elements.

The light projection optical system 14 adjusts the light distribution of the projected light by, for example, applying an optical effect (refraction, scattering, diffraction, etc.) to the projected light emitted from the light emitting unit 11. The light projection optical system 14 is configured using, for example, various lenses such as a collimating lens, optical components such as a reflecting mirror (mirror), and the like.

The light-receiving optical system 15 collects reflected light (return light), which is the light projected by the light projector and reflected by the measurement object 50 or the like, onto the light-receiving section 16 . The light receiving optical system 15 is configured using optical components such as various lenses such as a condenser lens, various filters such as a wavelength filter, and a reflecting mirror.

The light receiving section 16 includes one or more light receiving elements (a plurality of light receiving elements), or one or more light receiving element arrays (for example, light receiving elements are arranged in a linear (one-dimensional) or planar (two-dimensional) manner. It is composed of The above light receiving element is, for example, a photodiode, a SPAD (Single Photon Avalanche Diode), a balanced photodetector, or the like. The light receiving unit 16 photoelectrically converts the reflected light incident from the light receiving optical system 15 to generate a current (hereinafter referred to as "light receiving current") according to the intensity of the reflected light. The light receiving section 16 performs TOF measurement of a signal indicating the timing at which each light receiving element constituting the light receiving section 16 receives reflected light (hereinafter referred to as "light receiving timing") and the light receiving current generated by each light receiving element. input to device 117;

The TOF measurement device 117 determines the TOF based on the signal indicating the light emission timing inputted from the light emission control device 112 and the signal indicating the light reception timing inputted from the light receiving section 16. The TOF measurement device 117 is configured using, for example, a time measurement IC (Integrated Circuit) equipped with a TDC (Time to Digital Converter) circuit. The TOF measuring device 117 inputs the determined TOF and the light receiving current input from the light receiving section 16 to the arithmetic device 150.

The arithmetic unit 150 is configured using a processor (CPU (Central Processing Unit), MPU (Micro Processing Unit), ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), DSP (Digital Signal Processor), etc.). Ru. The arithmetic unit 150 generates information used for various measurements such as detection of the measurement target 50 and distance measurement based on the light reception current and TOF input from the TOF measurement device 117. The above information includes, for example, a histogram used in the Time Correlated Single Photon Counting method, distances to each point of the measurement target 50, and a point cloud (point cloud information). etc. Further, the arithmetic device 150 controls the light projection control device 112 and the light receiving section 16. The arithmetic unit 150 controls the above-mentioned light projection timing and light reception timing, for example, by controlling the light projection control device 112 and the light receiving unit 16, so that the processing related to histogram generation is sped up or optimized. . The information generated by the arithmetic device 150 is provided (transmitted) via the communication I/F 160 to devices that use the information (hereinafter referred to as "various usage devices 40").

The various utilization devices 40 , for example, create an environmental map using a point cloud, self-position estimation (SLAM (Simultaneous Localization and Mapping)) using a scan matching algorithm (NDT (Normal Distribution Transform), ICP (Iterative Closest Point), etc.) etc.

FIG. 2A is a schematic diagram illustrating the relationship between the light receiving section 16, the light receiving optical system 15, and the viewing range 51. The viewing range 51 is determined by the size (shape, size, light-receiving area) of the light-receiving region of the light-receiving section 16 and the focal length of the light-receiving optical system 15.

FIG. 2B is a schematic diagram illustrating the relationship between the light emitting unit 11, the light projection optical system 14, and the viewing range 51. The viewing range 51 is determined by the size (shape, size, light receiving area) of the light emitting region of the light emitting unit 11 and the focal length of the light projecting optical system 14.

In this way, the size of the viewing range 51 is restricted by the size of the light receiving section 16 and the size of the light emitting section 11. Therefore, the viewing range when using ready-made products as the light receiving section 16 and the light emitting section 11, for example, does not necessarily match the purpose or application of the system to which the measuring device 100 is applied. Furthermore, depending on the purpose and application of the measuring device 100, there is a need to increase measurement accuracy in a specific visual field range compared to other visual field ranges. For example, when flash LiDAR is applied to AD or ADAS, there is a need to improve measurement accuracy in a specific field of view such as far away from oncoming traffic. It is necessary to respond flexibly to these needs.

Therefore, in the measuring device 100 of this embodiment, a diffraction grating (diffractive optical element) is used as an element of the light receiving optical system 15 of the light receiver or the light emitting optical system 14 of the light projector, thereby meeting the above-mentioned needs. I'm trying. The specific configuration will be explained below.

<First embodiment: When using a diffraction grating in the light receiving optical system>
FIG. 3 shows a light receiver and a viewing range 51 of the light receiver (a first viewing range aligned in the +x direction in the figure) when a diffraction grating (diffraction optical element) is used in the light receiving optical system 15 of the light receiver. 51a, a second viewing range 51b, and a third viewing range 51c). In this figure, the elements of the light receiver (light-receiving optical system 15, light-receiving section 16) are depicted as viewed from a direction perpendicular to the optical axis of the light-receiving section 16 (viewed from the +y side). Further, in this figure, the viewing range 51 is depicted as a view viewed from the direction of the optical axis (a view viewed from the -z side). The arrows shown in the figure indicate the direction in which the projector projects light toward each viewing range 51 (first viewing range 51a, second viewing range 51b, third viewing range 51c), which enters the receiver from each viewing range. Represents reflected light caused by light. In this figure, the size of the light receiver is exaggerated.

As shown in the figure, the light-receiving optical system 15 includes a diffraction grating 151 on whose surface minute irregularities on the order of a wavelength are periodically formed, and other optical systems 152 (various lenses, various filters, etc.). In this embodiment, the diffraction grating 151 is a transmission phase grating.

As shown in the figure, the reflected light that enters the diffraction grating 151 from the first viewing range 51a (hereinafter referred to as "first reflected light") is +1st order diffracted light (first order diffracted light). The light enters another optical system 152 as light). The reflected light that enters the diffraction grating 151 from the second viewing range 51b adjacent to the first viewing range 51a (hereinafter referred to as "second reflected light") is the 0th order diffracted light (second order is incident on another optical system 152 as diffracted light). The reflected light (hereinafter referred to as "third reflected light") that enters the diffraction grating 151 from the third viewing range 51c adjacent to the second viewing range 51b is -1st order diffracted light (third The light is incident on another optical system 152 as diffracted light of the second order. Then, each reflected light (first reflected light, second reflected light, and third reflected light) that has entered the other optical system 152 is focused on the light receiving section 16.

In this way, by using the diffraction grating 151 as an element of the light receiving optical system 15, reflected light from each viewing range 51 (first viewing range 51a, second viewing range 51b, third viewing range 51c) can be reduced. Both can be focused on the light receiving section 16. Therefore, the field of view (FOV) of the light receiver can be expanded without expanding the light receiving area of the light receiving section 16 (without increasing the number of light receiving elements).

As shown in the figure, in this configuration, the reflected light (diffraction light) from each viewing range 51 (first viewing range 51a, second viewing range 51b, third viewing range 51c) is The light will be incident on the same light receiving element of the light receiving section 16. Therefore, when implemented in the measuring device 100, some kind of mechanism is required to distinguish from which viewing range 51 the reflected light is received.

The above mechanism, for example, projects light from the projector to each viewing range 51 (first viewing range 51a, second viewing range 51b, third viewing range 51c) at different timings for each viewing range 51. This can be achieved by doing this. In this case, for example, the arithmetic unit 150 controls the light projection control device 112 so that light is projected from the light projector at different timings for each viewing range 51, and the light receiving element of the light receiving unit 16 receives reflected light. Based on the timing, it is determined which viewing range 51 the reflected light comes from (hereinafter referred to as the "first method").

Further, for example, reflected light from each of the first viewing range 51a, the second viewing range 51b, and the third viewing range 51c (+1st-order diffracted light, 0th-order diffracted light, -1st-order diffracted light ) does not enter the same light-receiving element of the light-receiving section 16, the projector illuminates a part of each viewing range 51 (a part of the first viewing range 51a, a part of the first viewing range 51a where the light does not enter the same light-receiving element, (a partial area of the second visual field range 51b and a partial area of the third visual field range 51c), and the light may be emitted simultaneously for each selected area (hereinafter referred to as the "second method"). ). According to the second method, since light can be received simultaneously for each of the above viewing ranges 51, all the viewing ranges 51 (the first viewing range 51a, the second viewing range 51b, the third viewing range 51c) can reduce the time required for light projection (scan speed).

For example, as shown in FIG. 4A, the projector simultaneously projects light onto a band-shaped region 55 spanning a first viewing range 51a, a second viewing range 51b, and a third viewing range 51c. On the other hand, as shown in FIG. 4B, the direction in which the slits 1511 of the diffraction grating 151 (one unit of the grating (FIG. 6) consisting of convex portions and concave portions) is aligned with the extension of the above-mentioned band-shaped region 55 is shown in FIG. The diffraction grating 151 may be arranged in a positional relationship rotated by a predetermined angle α around the optical axis (Z axis in FIG. 4B) with respect to the direction (hereinafter referred to as the "third method"). ).

In this case, the thickness (distance (width) in the y direction in the figure) of the above-mentioned strip-shaped area 55 is set so that the reflected light from different viewing ranges 51 does not enter the light receiving section 16 at the same time. (in the example shown in the figure, the amount of deviation (step difference) in the y direction of adjacent viewing ranges 51).

FIG. 5A is an example of the visual field range 51 and an image of reflected light focused on the light receiving section 16 (light-receiving image) when the third method is adopted. As shown in the figure, reflected light from each viewing range 51 (+1st order diffracted light, 0th order diffracted light, -1st order diffracted light) is focused on different light receiving elements of the light receiving section 16.

Incidentally, if, for example, the optical axis of the diffraction grating 151 is made to coincide with the extending direction of the strip-shaped region 55, as shown in FIG. (reflected light from the strip-shaped area 55 of each viewing range 51) overlaps and is condensed at the same time.

According to the third method described above, light can be emitted and received at the same time for the strip-shaped area 55 extending from the first viewing range 51a to the third viewing range 51c, and the light projection for the entire viewing range 51 can be performed. The time (scanning speed) can be shortened.

As described above, by using the diffraction grating 151 as an element of the light-receiving optical system 15, the field of view (FOV) of the light receiver can be improved without expanding the light-receiving area of the light-receiving section 16 (without increasing the number of light-receiving elements). can be easily extended from the first viewing range 51a to the third viewing range 51c.

By the way, the following relationship exists between the angle θ between the incident light incident on the diffraction grating 151 and the diffracted light, the grating pitch d (grating interval), the wavelength λ of the incident light, and the diffraction order M.
[Number 1]
M×λ=d×sinθ...Formula 1
Therefore, by selecting the grating pitch d and the wavelength λ of the incident light, the field of view (FOV) of the light receiver can be adjusted. For example, when the wavelength λ of the incident reflected light is 905 nm, the diffraction angle θ of the diffraction grating 151 is set to 40° (the viewing angle of the first viewing range 51a is +20° to +60°, and the viewing angle of the second viewing range 51b is 40°). In order to set the angle to ±20° and the viewing angle of the third viewing range 51c to -20° to -60°, the grating pitch d may be set to 1.4 μm.

FIG. 6 is a diagram illustrating parameters that determine the characteristics of the diffraction grating 151. The diffraction efficiency (transmittance) of the diffraction grating 151 is determined by the grating density shown in the figure (the proportion occupied by the convex portions 1511a in the slits 1511) and the height of the convex portions 1511a. Therefore, by adjusting these values, each reflected light (+1st order diffracted light, 0 It is possible to adjust the diffraction efficiency (the amount of reflected light incident on the light receiving section 16) of the next diffracted light (-1st order diffracted light).

For example, in a diffraction grating 151 made of a material with a refractive index of 1.5 (synthetic quartz, acrylic, etc.) so that the diffraction angle is 40°, the height of the convex portions 1511a is 0.724 μm, and the grating density is 0.2, the amount of diffracted light is 100% of the incident light, the amount of +1st order diffracted light is 21.8%, the amount of 0th order diffracted light is 50%, and the amount of -1st order diffracted light is 21.8%. The amount of light is 21.7%. In addition, in the diffraction grating 151 made of the same material and diffraction angle, the amount of diffracted light when the height of the convex portion 1511a is 0.905 μm and the grating density is 0.65 is, assuming that the amount of incident light is 100%. , the amount of +1st order diffracted light is 31.1%, the amount of 0th order diffracted light is 33.1%, and the amount of −1st order diffracted light is 31.3%.

In this way, by selecting the grating pitch d of the diffraction grating 151 and the wavelength λ of the incident light, the viewing range 51 (light receiving range) of the light receiver can be adjusted to the viewing range required by the system to which it is applied. . In addition, by adjusting the values of parameters such as the refractive index, grating density, and height of the convex portion 1511a of the diffraction grating 151, each diffracted light (+1st order diffracted light, 0th order diffracted light) emitted from the diffraction grating 151 can be adjusted. , -1st order diffracted light) can be adjusted. Therefore, for example, it is possible to meet needs such as wanting to improve long-distance visibility in the direction of travel during driving, and wanting to improve measurement accuracy in a specific visual field range. In this way, the measuring device 100 of this embodiment can flexibly respond to the specifications required by the system to which it is applied.

<Second embodiment: When using a diffraction grating in the projection optical system>
FIG. 7 shows a light projector and a field of view of the light projector when a diffraction grating 141 having the same configuration as the diffraction grating 151 used in the light receiving optical system 15 described above is used in the light projecting optical system 14 of the light projector of the measuring device 100. 51 (light projection range) (first viewing range 51a, second viewing range 51b, third viewing range 51c). In this figure, the elements of the light projector (light projecting optical system 14 and light emitting section 11) are depicted as viewed from a direction perpendicular to the optical axis of the light emitting section 11 (viewed from the +y side). Further, in this figure, each viewing range 51 is depicted as a view viewed from the direction of the optical axis (a view viewed from the -z side). The arrows shown in the figure represent the correspondence between each diffracted light beam emitted from the projector and each viewing range 51 (first viewing range 51a, second viewing range 51b, third viewing range 51c). In this figure, the size of the projector is exaggerated.

The light projection optical system 14 includes a diffraction grating 141 and other optical systems 142 (various lenses, various filters, etc.). As shown in the figure, the light emitted from the light emitting unit 11 passes through another optical system 142 and enters the diffraction grating 141, and as a result, the +1st-order light is directed from the diffraction grating 141 toward the first viewing range 51a. Diffracted light, 0th-order diffracted light toward the second viewing range 51b, and -1st-order diffracted light toward the third viewing range 51c are emitted.

In this way, by using the diffraction grating 141 as an element of the light projection optical system 14, the field of view (FOV) of the light projector can be increased without expanding the light emitting area of the light emitting unit 11 (without increasing the number of light emitting elements). , can be easily extended to a range from the first visual field range 51a to the third visual field range 51c.

Note that, similarly to the case where the diffraction grating 151 is used in the light receiver, the viewing range 51 of the projector can be adjusted by selecting the grating pitch d of the diffraction grating 141 and the wavelength λ of the incident light. In addition, by adjusting the values of parameters such as the refractive index, grating density, and height of the convex portion of the diffraction grating 141, each diffracted light (+1st-order diffracted light, 0th-order diffracted light, -1st-order diffracted light) ) can be adjusted. Therefore, it is possible to flexibly respond to the specifications required by the system to which the measuring device 100 is applied.

In the first embodiment, a diffraction grating (diffraction optical element) is used as an element of the light receiving optical system 15 of the light receiver. In the second embodiment, a diffraction grating (diffraction optical element) is used as an element of the light projection optical system 14 of the light projector. In the measuring device 100B of the third embodiment described below, the above-mentioned needs are met by using an optical element having a prism structure as an element of the light receiving optical system 15B of the light receiver or the light projecting optical system 14B of the light emitter. We are taking measures. The specific configuration will be explained below.

<Third Embodiment: When using an optical element in the light receiving optical system>
FIG. 8 shows a light receiver and a viewing range 51 of the light receiver (a first viewing range lined up in the + 51a, a second viewing range 51b, and a third viewing range 51c). In the configuration shown in FIG. 8, the same components as those shown in FIG. 3 are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in the figure, the light receiving optical system 15B includes an optical element 151B having a prism structure and other optical systems 152 (various lenses, various filters, etc.).

FIG. 9A shows an external perspective view of the optical element 151B. As shown in the figure, the optical element 151B has a first entrance surface 151a, a second entrance surface 151b, and a third entrance surface 151c. The first incident surface 151a is formed on the upper surface side (+z side in the figure) of the optical element 151B, and the first reflected light from the first viewing range 51a is incident on the first incident surface 151a. The second incident surface 151b is formed continuously to the first incident surface 151a, and the second reflected light from the second visual field range 51b continuous to the first visual field range 51a is reflected from the second incident surface 151b. incident on . The third entrance surface 151c is formed continuously to the second entrance surface 151b, and the third reflected light from the third viewing range 51c that is continuous to the second viewing range 51b is reflected from the third entrance surface 151c. incident on . The optical element 151B receives the refracted light of the first reflected light, the transmitted light of the second reflected light, and the refracted light of the third reflected light on the lower surface side (-z side in the figure) of the optical element 151B. It has an output surface 151o that outputs light to the portion 16. The first entrance surface 151a, the second entrance surface 151b, the third entrance surface 151c, and the exit surface 151o are all flat surfaces.

FIG. 9B is a side view of the optical element 151B viewed from the +y side of FIG. 9A. The second entrance surface 151b is parallel to the exit surface 151o. The first entrance surface 151a is inclined toward the +z side at an inclination angle θ1 with respect to the second entrance surface 151b, with the first boundary line 1511B between the second entrance surface 151b and the second entrance surface 151b as a fold. A prism structure is formed on one end side (-x side). Further, the third entrance surface 151c is inclined toward the +z side at an inclination angle θ2 with the second boundary line 1512 between the second entrance surface 151b and the second entrance surface 151b as a fold line. A prism structure is formed on the other end side (+x side) of 151B.

Returning to FIG. 8, the optical axis of the optical element 151B (a line passing through the center line of the second entrance surface 151b and perpendicular to the exit surface 151o (normal to the exit surface 151o), The optical axis 1515 ) is arranged to coincide with the optical axes of the other optical system 152 and the light receiving section 16 .

As shown in the figure, the first reflected light from the first viewing range 51a enters the first incident surface 151a of the optical element 151B and is refracted, and then exits from the exit surface 151o and is transmitted to other optical devices. The light passes through the system 152 and is focused on the light receiving section 16 . The second reflected light from the second viewing range 51b enters the second entrance surface 151b of the optical element 151B, then exits from the exit surface 151o, passes through another optical system 152, and enters the light receiving section 16. The light is focused. The third reflected light from the third viewing range 51c enters the third entrance surface 151c of the optical element 151B and is refracted, then exits from the exit surface 151o, passes through another optical system 152, and is received. The light is focused on the portion 16.

In this way, by using the optical element 151B as an element of the light receiving optical system 15B, reflected light from each viewing range 51 (first viewing range 51a, second viewing range 51b, third viewing range 51c) can be reduced. Both can be focused on the light receiving section 16. Therefore, the field of view (FOV) of the light receiver can be expanded without expanding the light receiving area of the light receiving section 16 (without increasing the number of light receiving elements).

As shown in the figure, in this configuration, the reflected light from each viewing range 51 (the first viewing range 51a, the second viewing range 51b, and the third viewing range 51c) is reflected from the light receiving unit 16. The light will be incident on the same light-receiving element. Therefore, when implemented in the measuring device 100B, some kind of mechanism is required to distinguish from which viewing range 51 the reflected light is received.

The above mechanism may use, for example, the first method and the second method described above.

For example, as shown in FIG. 10A, the projector simultaneously projects light onto a band-shaped region 55 spanning a first viewing range 51a, a second viewing range 51b, and a third viewing range 51c. On the other hand, in the light receiver, as shown in FIG. 10B, the first entrance surface 151a is further inclined with respect to the second entrance surface 151b at an inclination angle φ1 along the first boundary line 1511B. Furthermore, in the light receiver, as shown in FIG. 10B, the third entrance surface 151c is further separated from the first entrance surface 151a along the second boundary line 1512 with respect to the second entrance surface 151b. It is tilted in the opposite direction at an angle of inclination φ2 (hereinafter referred to as the "fourth method").

In this case, the first entrance surface 151a may be tilted by rotating around an axis 1516a parallel to the x-axis set within the plane of the first entrance surface 151a, or It may also be tilted by rotating about an axis 1517a extending in the direction. Similarly, the third entrance surface 151c may be tilted by rotating around an axis 1516b parallel to the x-axis set within the plane of the third entrance surface 151c, or may be tilted in the same direction as the x-axis. It may be tilted by rotating about the extending axis 1517b.

In the case where the light receiver has the configuration shown in FIGS. 10A and 10B, an example of the visual field range 51 and the image (received light image) of the reflected light focused on the light receiving section 16 is the same as that in FIG. 5A. As shown in the figure, the reflected light from each viewing range 51 is focused on different light receiving elements of the light receiving section 16.

Incidentally, when similar light is projected (simultaneously illuminates the band-shaped area 55 extending from the first viewing range 51a to the third viewing range) using the optical element 151B having the configuration shown in FIG. 9A, As shown in FIG. 5B, reflected light from each viewing range 51 (reflected light from the strip-shaped area 55 of each viewing range 51) overlaps and is focused on the same light receiving element of the light receiving unit 16 at the same time.

According to the fourth method described above, light can be emitted and received simultaneously for the strip-shaped area 55 extending from the first viewing range 51a to the third viewing range 51c, and the light projection for the entire viewing range 51 can be performed. The time (scanning speed) can be shortened.

As described above, by using the optical element 151B having a simple configuration as an element of the light-receiving optical system 15B, the light-receiving area of the light-receiving section 16 can be expanded (without increasing the number of light-receiving elements). The field of view (FOV) can be easily expanded from the first field of view 51a to the third field of view 51c. Furthermore, by adjusting the inclination angles θ1, θ2 and the inclination angles φ1, φ2, the light receiving range (first viewing range 51a and third viewing range 51c) can be adjusted to meet the requirements of the applied system. We can respond flexibly to specifications.

<Fourth embodiment: When using an optical element in the light projection optical system>
FIG. 11 shows a light projector and a field of view range 51 (light projection range) ( FIG. 4 is a diagram illustrating the relationship between a first visual range 51a, a second visual range 51b, and a third visual range 51c). In the configuration shown in FIG. 11, the same components as those shown in FIG. 7 are denoted by the same reference numerals, and the description thereof will be omitted. The arrows shown in the figure represent the correspondence between the light emitted from the optical element 141B and each viewing range 51 (first viewing range 51a, second viewing range 51b, and third viewing range 51c).

As shown in the figure, the light projection optical system 14B includes an optical element 141B having a prism structure and other optical systems 142 (various lenses, various filters, etc.).

FIG. 12A shows an external perspective view of the optical element 141B. As shown in the figure, the optical element 141B has an entrance surface 141i on the lower surface side (-z side in the figure) of the optical element 141B, into which light from the light emitting section 11 enters. Further, the optical element 141B has a first output surface 141a, a second output surface 141b, and a third output surface 141c. The first output surface 141a outputs the light incident on the input surface 141i from the light emitting section 11 toward the first viewing range 51a toward the upper surface side (+z side in the figure) of the optical element 141B. The second output surface 141b is formed continuously from the first output surface 141a, and outputs the light that is incident on the input surface 141i from the light emitting section 11 toward the second viewing range 51b. The third output surface 141c is formed continuously with the second output surface 141b, and outputs the light that is incident on the input surface 141i from the light emitting section 11 toward the third viewing range 51c. The entrance surface 141i, the first exit surface 141a, the second exit surface 141b, and the third exit surface 141c are all flat surfaces.

FIG. 12B is a side view of the optical element 141B viewed from the −y side of FIG. 9A. The entrance surface 141i is parallel to the second exit surface 141b. The first exit surface 141a is inclined toward the +z side at an inclination angle θ1 with respect to the second exit surface 141b, with the first boundary line 1411 between the second exit surface 141b and the second exit surface 141b as a fold. A prism structure is formed on one end side (-x side). The third exit surface 141c is inclined toward the +z side at an inclination angle θ2 with the second boundary line 1412 between the second exit surface 141b and the second exit surface 141b as a fold line, thereby increasing the angle of the optical element 141B. A prism structure is formed on the other end side (+x side).

Returning to FIG. 11, the optical element 141B has an optical axis (a line passing through the center line of the second exit surface 141b and perpendicular to the entrance surface 141i (normal to the entrance surface 141i, denoted by the reference numeral in FIG. 12B). The optical axis 1415) is arranged to coincide with the optical axes of the other optical system 142 and the light emitting section 11.

As shown in the figure, the light emitted from the light emitting section 11 passes through another optical system 142 and enters the optical element 141B. As a result, from the optical element 141B, the first transmitted light is refracted at the first output surface 141a and goes to the first viewing range 51a, and the first transmitted light is transmitted through the second output surface 141b and goes to the second viewing range 51b. The second transmitted light and the third transmitted light that is refracted by the third output surface 141c and directed toward the third viewing range 51c are emitted.

In this way, by using the optical element 141B as an element of the light projection optical system 14B, the field of view (FOV) of the light emitter can be increased without expanding the light emitting area of the light emitting unit 11 (without increasing the number of light emitting elements). , can be easily extended to a wide range from the first viewing range 51a to the third viewing range 51c. Furthermore, by adjusting the inclination angles θ1 and θ2, the light projection range (the first viewing range 51a and the third viewing range 51c) can be adjusted to meet the specifications required by the system to which the measuring device 100B is applied. Able to respond flexibly.

Although the embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above-described embodiments, and includes various modifications. Furthermore, the configurations of the embodiments described above are explained in detail in order to explain the present disclosure in an easy-to-understand manner, and the embodiments are not necessarily limited to those having all the configurations described. Further, some of the configurations of the above embodiments can be added to, deleted from, or replaced with other configurations.

For example, in the above description, the case where there are three viewing ranges (light emitting range, light receiving range) (the first viewing range 51a, the second viewing range 51b, and the third viewing range 51c) has been described as an example. The disclosure can also be applied to cases where there are two viewing ranges or four or more viewing ranges.

Furthermore, for example, the configurations of the emitter and the light receiver described above (the configuration in which the diffraction grating 151 is used as an element of the light receiving optical system 15, and the configuration in which the diffraction grating 141 is used as an element in the light emitting optical system 14) include both of these. It may be applied to the measuring device 100, or only one of them may be applied.

Also, for example, in the above, the viewing range was expanded by using diffracted light of three different orders (+1st order, 0th order, -1st order) of the diffraction grating, but it is possible to expand the viewing range by using diffracted light of orders other than these. The viewing range may be expanded.

Furthermore, for example, the configurations of the light emitter and the light receiver described above (the configuration in which the optical element 151B is used as an element of the light receiving optical system 15B, and the configuration in which the optical element 141B is used as an element in the light emitting optical system 14B) include both of these. It may be applied to the measuring device 100B, or only one of them may be applied.

This application claims priority based on Japanese Application No. 2022-120204 filed on July 28, 2022 and Japan Application No. 2022-120205 filed on July 28, 2022, and All contents are hereby incorporated by reference.

Claims

comprising a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range,
The light receiver includes a light receiving section and a transmission type diffraction grating,
The diffraction grating is configured such that a first reflected light from the first viewing range is incident on the light receiving section as a first-order diffracted light, and a second reflected light from a second viewing range aligned with the first viewing range is arranged in the diffraction grating. is arranged so that the reflected light enters the light receiving section as second-order diffracted light,
measuring device.
The measuring device according to claim 1,
The light projector projects light toward the first viewing range and the second viewing range at different timings, respectively.
measuring device.
The measuring device according to claim 1,
The light receiving section includes a plurality of light receiving elements,
The diffraction grating is arranged such that the direction in which the slits of the diffraction grating are arranged coincides with the direction in which the first viewing range and the second viewing range are arranged,
The projector is directed toward a portion of the first viewing range and a portion of the second viewing range such that the first reflected light and the second reflected light do not enter the same light receiving element. emits light at the same time,
measuring device.
The measuring device according to claim 1,
The light receiving section includes a plurality of light receiving elements arranged in a planar manner,
The projector simultaneously projects light onto a strip-shaped area extending from the first viewing range to the second viewing range,
The diffraction grating has a direction in which the slits of the diffraction grating are arranged with respect to a stretching direction of the band-shaped region so that the first reflected light and the second reflected light are respectively incident on different light receiving elements. arranged in a positional relationship rotated by a predetermined angle around the optical axis of the diffraction grating,
measuring device.
comprising a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range,
The light receiver includes a light receiving section and a transmission type diffraction grating,
The diffraction grating is
The first reflected light from the first viewing range enters the light receiving section as +1st order diffracted light,
A second reflected light from a second viewing range aligned with the first viewing range enters the light receiving section as zero-order diffracted light,
In the direction from the first viewing range to the second viewing range, third reflected light from a third viewing range aligned with the second viewing range enters the light receiving section as −1st order diffracted light. are arranged so that
measuring device.
The measuring device according to claim 5,
The projector projects light toward the first viewing range, the second viewing range, and the third viewing range at different timings, respectively.
measuring device.
The measuring device according to claim 5,
The light receiving section includes a plurality of light receiving elements arranged in a planar manner,
The diffraction grating is arranged such that the direction in which the slits of the diffraction grating are arranged coincides with the direction in which the slits are arranged from the first viewing range to the third viewing range,
The light projector includes a portion of the first visual field range in which none of the first reflected light, the second reflected light, and the third reflected light enter the light receiving element; Simultaneously projecting light toward a part of the second viewing range and a part of the third viewing range;
measuring device.
The measuring device according to claim 5,
The light receiving section includes a plurality of light receiving elements arranged in a planar manner,
The projector simultaneously projects light onto a strip-shaped area extending from the first viewing range to the third viewing range,
The diffraction grating is arranged such that the slits of the diffraction grating are arranged in a direction such that the first reflected light, the second reflected light, and the third reflected light are respectively incident on different light receiving elements. arranged in a positional relationship rotated by a predetermined angle around the optical axis of the diffraction grating with respect to the stretching direction of the band-shaped region;
measuring device.
A light receiver that receives reflected light generated by a light projector projecting light toward a viewing range,
including a light receiving section and a transmission type diffraction grating,
The diffraction grating is configured such that a first reflected light from the first viewing range is incident on the light receiving section as a first-order diffracted light, and a second reflected light from a second viewing range aligned with the first viewing range is arranged in the diffraction grating. is arranged so that the reflected light enters the light receiving section as second-order diffracted light,
Receiver.
A light receiver that receives reflected light generated by a light projector projecting light toward a viewing range,
The light receiver includes a light receiving section and a transmission type diffraction grating,
The diffraction grating is
The first reflected light from the first viewing range enters the light receiving section as +1st order diffracted light,
A second reflected light from a second viewing range aligned with the first viewing range enters the light receiving section as zero-order diffracted light,
In the direction from the first viewing range to the second viewing range, third reflected light from a third viewing range aligned with the second viewing range enters the light receiving section as -1st order diffracted light. are arranged so that
Receiver.
comprising a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range,
The projector includes a light emitting section and a transmission type diffraction grating,
The diffraction grating emits first-order diffracted light, which is generated when light from the light emitting section passes through the diffraction grating, toward a first viewing range, and the light transmits through the diffraction grating. arranged so as to emit second-order diffracted light generated by the second order toward a second viewing range aligned with the first viewing range,
measuring device.
comprising a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range,
The projector includes a light emitting section and a transmission type diffraction grating,
The diffraction grating is
Emitting +1st-order diffracted light generated when light from the light emitting part passes through the diffraction grating toward a first viewing range,
Emitting zero-order diffracted light caused by the light passing through the diffraction grating toward a second viewing range aligned with the first viewing range,
-1st-order diffracted light generated when the light passes through the diffraction grating is directed from the first viewing range to the second viewing range in a third viewing range aligned with the second viewing range. It is arranged so that it emits toward the
measuring device.
A floodlight that emits light toward a viewing range,
including a light emitting part and a transmission type diffraction grating,
The diffraction grating is
Emitting first-order diffracted light generated when light from the light emitting part passes through the diffraction grating toward a first viewing range,
The second-order diffracted light generated when the light passes through the diffraction grating is emitted toward a second viewing range aligned with the first viewing range.
Floodlight.
A floodlight that emits light toward a viewing range,
including a light emitting part and a transmission type diffraction grating,
The diffraction grating is
Emitting +1st-order diffracted light generated when light from the light emitting part passes through the diffraction grating toward a first viewing range,
Emitting zero-order diffracted light caused by the light passing through the diffraction grating toward a second viewing range aligned with the first viewing range,
-1st-order diffracted light generated when the light passes through the diffraction grating is directed from the first viewing range to the second viewing range in a third viewing range aligned with the second viewing range. It is arranged so that it emits toward the
Floodlight.
comprising a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range,
The light receiver includes a light receiving section and a transmission type optical element,
The optical element is
a first incidence surface on which the first reflected light from the first viewing range is incident;
a second entrance surface that is formed continuously with the first entrance surface and on which second reflected light from a second viewing range that is continuous with the first viewing range is incident;
an output surface that outputs the first reflected light and the second reflected light to the light receiving section;
has
The first entrance surface, the second entrance surface, and the exit surface are all flat surfaces,
The second entrance surface is inclined with respect to the first entrance surface with a boundary line with the first entrance surface as a fold.
measuring device.
16. The measuring device according to claim 15,
The light projector projects light toward the first viewing range and the second viewing range at different timings, respectively.
measuring device.
16. The measuring device according to claim 15,
The light receiving section includes a plurality of light receiving elements,
The projector projects light toward the first viewing range and the second viewing range so that the first reflected light and the second reflected light enter different light receiving elements, respectively.
measuring device.
16. The measuring device according to claim 15,
The light receiving section includes a plurality of light receiving elements arranged in a planar manner,
The second entrance surface is further inclined along the boundary line with respect to the first entrance surface,
The projector includes a strip-shaped light beam extending from the first viewing range to the second viewing range so that the first reflected light and the second reflected light are respectively incident on different light receiving elements of the light receiving section. illuminate an area at the same time,
measuring device.
comprising a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range,
The light receiver includes a light receiving section and a transmission type optical element,
The optical element is
a first incidence surface on which the first reflected light from the first viewing range is incident;
a second entrance surface that is formed continuously with the first entrance surface and on which the second reflected light from the second viewing range is incident;
a third entrance surface that is formed continuously with the second entrance surface and on which the third reflected light from the third viewing range is incident;
an output surface that outputs the first reflected light, the second reflected light, and the third reflected light to the light receiving section;
has
The first entrance surface, the second entrance surface, the third entrance surface, and the exit surface are all flat surfaces,
the first entrance surface is inclined with respect to the second entrance surface with a first boundary line with the second entrance surface as a fold;
The third entrance surface is inclined with respect to the second entrance surface with a second boundary line with the second entrance surface as a fold.
measuring device.
The measuring device according to claim 19,
The projector projects light toward the first viewing range, the second viewing range, and the third viewing range at different timings, respectively.
measuring device.
The measuring device according to claim 19,
The light receiving section includes a plurality of light receiving elements,
The projector is arranged such that the first visual field range, the second visual field range, and the second visual field range are arranged so that the first reflected light, the second reflected light, and the third reflected light are respectively incident on different light receiving elements. and projecting light toward the third viewing range;
measuring device.
The measuring device according to claim 19,
The light receiving section includes a plurality of light receiving elements arranged in a planar manner,
The first entrance surface is further inclined along the first boundary line with respect to the second entrance surface,
The third entrance surface is further inclined with respect to the second entrance surface along the second boundary line in a direction opposite to the first entrance surface,
The projector is arranged to extend from the first visual field range to the first reflected light such that the first reflected light, the second reflected light, and the third reflected light are respectively incident on different light receiving elements of the light receiving section. Simultaneously illuminates a strip-shaped area spanning 3 viewing ranges.
measuring device.
A light receiver that receives reflected light generated by a light projector projecting light toward a viewing range,
including a light receiving section and a transmission type optical element,
The optical element is
a first incidence surface on which the first reflected light from the first viewing range is incident;
a second entrance surface that is formed continuously with the first entrance surface and on which second reflected light from a second viewing range that is continuous with the first viewing range is incident;
an output surface that outputs the first reflected light and the second reflected light to the light receiving section;
has
The first entrance surface, the second entrance surface, and the exit surface are all flat surfaces,
The second entrance surface is inclined with respect to the first entrance surface with a boundary line with the first entrance surface as a fold.
Receiver.
24. The light receiver according to claim 23,
The light receiving section includes a plurality of light receiving elements arranged in a planar manner,
The second entrance surface is further inclined along the boundary line with respect to the first entrance surface.
Receiver.
A light receiver that receives reflected light generated by a light projector projecting light toward a viewing range,
including a light receiving section and a transmission type optical element,
The optical element is
a first incidence surface on which the first reflected light from the first viewing range is incident;
a second entrance surface that is formed continuously with the first entrance surface and on which the second reflected light from the second viewing range is incident;
a third entrance surface that is formed continuously with the second entrance surface and on which the third reflected light from the third viewing range is incident;
an output surface that outputs the first reflected light, the second reflected light, and the third reflected light to the light receiving section;
has
The first entrance surface, the second entrance surface, the third entrance surface, and the exit surface are all flat surfaces,
the first entrance surface is inclined with respect to the second entrance surface with a first boundary line with the second entrance surface as a fold;
The third entrance surface is inclined with respect to the second entrance surface with a second boundary line with the second entrance surface as a fold.
Receiver.
26. The light receiver according to claim 25,
The light receiving section includes a plurality of light receiving elements arranged in a planar manner,
The first entrance surface is further inclined along the first boundary line with respect to the second entrance surface,
The third entrance surface is further inclined with respect to the second entrance surface along the second boundary line in a direction opposite to the first entrance surface.
Receiver.
comprising a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range,
The projector includes a light emitting section and a transmission type optical element,
The optical element is
an entrance surface on which light from the light emitting section enters;
a first output surface that outputs light incident on the input surface toward a first viewing range;
a second output surface that outputs the light incident on the input surface toward a second viewing range;
has
The incident surface, the first exit surface, and the second exit surface are all flat surfaces,
The second output surface is inclined with respect to the first output surface with a boundary line with the second output surface as a fold line.
measuring device.
comprising a light projector and a light receiver that receives reflected light generated by the projector projecting light toward a viewing range,
The projector includes a light emitting section and a transmission type optical element,
The optical element is
an entrance surface on which light from the light emitting section enters;
a first output surface that outputs light incident on the input surface toward a first viewing range;
a second output surface that outputs the light incident on the input surface toward a second viewing range;
a third output surface that outputs the light incident on the input surface toward a third viewing range;
has
The incident surface, the first exit surface, the second exit surface, and the third exit surface are all flat surfaces,
The first exit surface is inclined with respect to the second exit surface with a first boundary line with the second exit surface as a fold,
The third exit surface is inclined with respect to the second exit surface with a second boundary line with the second exit surface as a fold.
measuring device.
A floodlight that emits light toward a viewing range,
Including a light emitting part and a transmission type optical element,
The optical element is
an entrance surface on which light from the light emitting section enters;
a first output surface that outputs light incident on the input surface toward a first viewing range;
a second output surface that outputs the light incident on the input surface toward a second viewing range;
has
The incident surface, the first exit surface, and the second exit surface are all flat surfaces,
The second output surface is inclined with respect to the first output surface with a boundary line with the second output surface as a fold line.
Floodlight.
A floodlight that emits light toward a viewing range,
Including a light emitting part and a transmission type optical element,
The optical element is
an entrance surface on which light from the light emitting section enters;
a first output surface that outputs light incident on the input surface toward a first viewing range;
a second output surface that outputs the light incident on the input surface toward a second viewing range;
a third output surface that outputs the light incident on the input surface toward a third viewing range;
has
The incident surface, the first exit surface, the second exit surface, and the third exit surface are all flat surfaces,
The first exit surface is inclined with respect to the second exit surface with a first boundary line with the second exit surface as a fold,
The third exit surface is inclined with respect to the second exit surface with a second boundary line with the second exit surface as a fold.
Floodlight.