Electromagnetic wave detection device

Abstract

To provide an optical system shared by a plurality of detectors with optical characteristics suitable for the respective detectors.SOLUTION: An electromagnetic wave detection device 10 has a first detection unit 13, a second detection unit 14, a first diaphragm 15, a second diaphragm 16, and a control unit 18. The first detection unit 13 detects a reflected wave incident from an incident unit 12. The second detection unit 14 detects an electromagnetic wave incident from the incident unit 12. The second diaphragm 16 has a second area and a third area. The second area is smaller than a first area. The third area is located on the periphery of the second area. The third area does not transmit an electromagnetic wave traveling to the second detection unit 14. The control unit 18 acquires first space information on a space based on detection of an electromagnetic wave performed by the first detection unit 13. The control unit 18 acquires second space information on a space based on detection of an electromagnetic wave performed by the second detection unit 14.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electromagnetic wave detection device. [Background technology]

[0002] In recent years, devices have been developed that obtain information about the surroundings from the detection results of multiple detectors that detect electromagnetic waves. For example, a device is known that measures the position of an object in an image by using the reflected waves of electromagnetic waves irradiated onto the object (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-200927 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a configuration in which an optical system that guides electromagnetic waves to a plurality of detectors is shared, it has been difficult to design and manufacture the optical system so that its characteristics, such as brightness, are suited to each detector.

[0005] Therefore, an object of the present disclosure, made in consideration of the above-mentioned problems with the conventional technology, is to provide an optical system shared by multiple detectors with optical characteristics suitable for each detector. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, an electromagnetic wave detection device according to a first aspect comprises: An irradiation unit that radiates electromagnetic waves into space; an incident section into which electromagnetic waves including a reflected wave of the electromagnetic wave radiated by the irradiation section and reflected by a target are incident; a first detection unit that detects a reflected wave incident from the incident unit; A second detection unit that detects the electromagnetic wave incident from the incident unit; a first aperture having a first region that passes electromagnetic waves traveling to the first detection unit and the second detection unit; a second aperture having a second region that passes electromagnetic waves traveling to the first detection unit and the second detection unit and is smaller than the first region, and a third region around the second region that does not pass electromagnetic waves traveling to the second detection unit; an optical system that guides a first portion of the electromagnetic wave that has passed through the first aperture and the second aperture, the first portion including the reflected wave, to the first detection unit, and guides a second portion excluding the first portion to the second detection unit; a control unit that acquires first spatial information about the space based on detection of electromagnetic waves by the first detection unit, and acquires second spatial information about the space based on detection of electromagnetic waves by the second detection unit, The first aperture and the first region have a minor axis in a direction in which the irradiation unit is disposed relative to the incident unit, and a major axis in a direction intersecting the direction in which the irradiation unit is disposed, The resolution of the first spatial information is lower than the resolution of the second spatial information. Ku, the second region includes a wavelength filter that passes electromagnetic waves in a band including the wavelength of the electromagnetic waves emitted by the irradiation unit and electromagnetic waves in a visible light band; The third region includes a wavelength filter that passes electromagnetic waves in a band including the wavelength of the electromagnetic waves emitted by the irradiation unit and blocks electromagnetic waves in a visible light band. .

[0007] As described above, the solutions of the present disclosure have been described as devices and systems, but the present disclosure can also be realized in aspects that include these, and can also be realized as methods, programs, and storage media having programs recorded thereon that are substantially equivalent to these, and it should be understood that these are also encompassed within the scope of the present disclosure. Effect of the Invention

[0008] According to the electromagnetic wave detection device of the present disclosure having the above-described configuration, the optical system shared by the multiple detectors has optical characteristics suitable for each of the detectors. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing a schematic configuration of an electromagnetic wave detection device according to an embodiment of the present invention; [Diagram 2] 2 is a layout diagram of the irradiation section, the incidence section, and the first aperture in FIG. 1, as viewed from the optical axis direction of the incidence section. [Diagram 3] FIG. 2 is a front view of the second aperture of FIG. 1 in comparison with the first aperture. [Figure 4] 2 is a partial state diagram of the electromagnetic wave detection device for explaining the traveling direction of the electromagnetic wave in a first state and a second state of a switching element in a switching section of the electromagnetic wave detection device of FIG. 1. [Diagram 5] 2 is a timing chart showing the emission and detection times of electromagnetic waves, for explaining the principle of distance measurement by the distance measuring sensor constituted by the irradiation unit, first detection unit, and control unit in FIG. [Figure 6] FIG. 2 is a side view of a moving body equipped with the electromagnetic wave detection device of FIG. [Figure 7] 4 is a flowchart for explaining an aperture adjustment process executed by a control unit in FIG. [Figure 8] FIG. 11 is a partial configuration diagram showing a schematic configuration of a modified example of the electromagnetic wave detection device according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of an electromagnetic wave detection device to which the present disclosure is applied will be described with reference to the drawings.

[0011] As shown in FIG. 1, an electromagnetic wave detection device 10 according to one embodiment of the present disclosure includes an irradiation section 11, an incidence section 12, a first detection section 13, a second detection section 14, a first aperture 15, a second aperture 16, an optical system 17, and a control section 18.

[0012] In the following figures, the dashed lines connecting the functional blocks indicate the flow of control signals or information to be communicated. The communication indicated by the dashed lines may be wired communication or wireless communication. In addition, the solid lines protruding from each functional block indicate beam-shaped electromagnetic waves.

[0013] The irradiation unit 11 radiates electromagnetic waves into space. The irradiation unit 11 may change the irradiation position of the electromagnetic waves radiated to the object ob in the space by radiating the electromagnetic waves in a plurality of different directions in the space. The irradiation unit 11 may scan the object ob with the radiated electromagnetic waves. In this embodiment, the irradiation unit 11 may configure a scanning distance measuring sensor in cooperation with a first detection unit 13 described later. The irradiation unit 11 may scan the object ob in a one-dimensional direction or a two-dimensional direction. In this embodiment, the irradiation unit 11 scans the object ob in a two-dimensional direction.

[0014] The irradiation unit 11 is configured so that at least a part of the radiation area of ​​the electromagnetic waves is included in the detection range of the electromagnetic waves in the electromagnetic wave detection device 10. More specifically, the irradiation unit 11 is configured so that at least a part of the radiation area of ​​the radiated electromagnetic waves is included in the detection range of the first detection unit 13. Therefore, at least a part of the reflected waves of the radiated electromagnetic waves from the target ob can be detected by the first detection unit 13.

[0015] Specifically, the irradiation unit 11 may include a light source unit 19 and a reflection unit 20 .

[0016] The light source unit 19 may emit at least one of infrared rays, visible light, ultraviolet rays, and radio waves. In this embodiment, the light source unit 19 emits infrared rays. The light source unit 19 may emit electromagnetic waves in the form of a narrow beam, for example, 0.5°. The light source unit 19 may also emit electromagnetic waves in pulses. The light source unit 19 may switch between emitting and stopping electromagnetic waves based on the control of the control unit 18, which will be described later. The light source unit 19 includes, for example, an LD (Laser Diode) and an LED (Light Emitting Diode).

[0017] The reflecting unit 20 may reflect the electromagnetic waves emitted from the light source unit 19 while changing the direction, thereby emitting the electromagnetic waves emitted by the light source unit 19 in a plurality of different directions in space. The reflecting unit 20 may change the direction in which the electromagnetic waves are reflected based on the control of the control unit 18, which will be described later. The reflecting unit 20 includes, for example, a MEMS (Micro Electro Mechanical Systems) mirror, a polygon mirror, and a galvanometer mirror.

[0018] The irradiation unit 11 may radiate electromagnetic waves into space without passing through the incident unit 12. Alternatively, the irradiation unit 11 may radiate electromagnetic waves into space through the incident unit 12 by providing a mirror or the like on the image side of the incident unit 12, for example.

[0019] Electromagnetic waves from space are incident on the incident unit 12. The electromagnetic waves from the space may include reflected waves that are electromagnetic waves emitted by the irradiation unit 11 and reflected by an object ob in the space. The incident unit 12 may include, for example, at least one of a lens and a mirror, and may form an image of the object ob that is the subject.

[0020] The first detection unit 13 detects the reflected wave incident from the incident unit 12, in other words, the reflected wave reflected by an object ob in the space of the electromagnetic wave radiated by the irradiation unit 11, which is included in the electromagnetic wave incident on the incident unit 12. The first detection unit 13 may detect at least any of the electromagnetic waves of infrared rays, visible light, ultraviolet rays, and radio waves. The first detection unit 13 may detect electromagnetic waves in the same band as the electromagnetic wave radiated by the irradiation unit 11. The first detection unit 13 may transmit detection information indicating that the reflected wave from the object has been detected to the control unit 18 as a signal.

[0021] More specifically, the first detection unit 13 includes elements constituting a distance measurement sensor. For example, the first detection unit 13 includes a single element such as an APD (Avalanche PhotoDiode), a PD (PhotoDiode), and a distance measurement image sensor. The first detection unit 13 may also include an element array such as an APD array, a PD array, a distance measurement imaging array, and a distance measurement image sensor.

[0022] As described later, the reflected wave is incident on the first detection unit 13 via the optical system 17. The first detection unit 13 may be provided near an imaging position of an image of an object ob that is a predetermined position away from the incident unit 12, formed by the incident unit 12 via the optical system 17. Alternatively, the first detection unit 13 may be provided near an imaging position of an imaging element such as a lens or a mirror that is provided on the path of the electromagnetic wave traveling via the incident unit 12, as described later.

[0023] The second detection unit 14 detects electromagnetic waves incident from the incident unit 12. As described later, electromagnetic waves are incident on the second detection unit 14 via the optical system 17. The second detection unit 14 may be provided near or at the image-forming position of an image of an object ob, which is a predetermined position away from the incident unit 12, formed by the incident unit 12 via the optical system 17.

[0024] The second detection unit 14 may include an element array. For example, the second detection unit 14 may include an imaging element such as an image sensor or an imaging array, capture an image formed by electromagnetic waves on a detection surface, and generate image information corresponding to the captured object ob. More specifically, the second detection unit 14 may capture an image of visible light. The second detection unit 14 may transmit the generated image information to the control unit 18 as a signal.

[0025] The second detection unit 14 may capture images other than visible light, such as images of infrared light, ultraviolet light, and radio waves. The second detection unit 14 may include a distance measurement sensor. In a configuration in which the second detection unit 14 includes a distance measurement sensor, the electromagnetic wave detection device 10 may obtain image-like distance information by the second detection unit 14. The second detection unit 14 may also include a thermosensor, etc. In a configuration in which the second detection unit 14 includes a thermosensor, the electromagnetic wave detection device 10 may obtain image-like temperature information by the second detection unit 14.

[0026] The first aperture 15 has a first region that passes the electromagnetic waves traveling to the first detection unit 13 and the second detection unit 14. The first aperture 15 may adjust the amount of the electromagnetic waves passing therethrough by preventing the electromagnetic waves from traveling to the first detection unit 13 and the second detection unit 14 outside the first region.

[0027] The shape of the first region in the first aperture 15 may be any shape, such as a circle, an ellipse, a rectangle with rounded corners, etc. As shown in Fig. 2, the first region a1 may have a major axis in a direction intersecting with the arrangement direction of the irradiation unit 11 relative to the incidence unit 12. More specifically, the first region a1 may have a major axis in a direction perpendicular to the arrangement direction.

[0028] The first region a1 of the first aperture 15 may be a wavelength filter capable of transmitting electromagnetic waves traveling to the first detection unit 13 and the second detection unit 14, such as visible light and electromagnetic waves emitted by the irradiation unit 11 reflected by an object. Alternatively, the first aperture 15 may be a variable aperture whose aperture size is variable, in other words, whose size of the first region a1 of the first aperture 15 is variable. In a configuration in which the first aperture 15 is a variable aperture, the first aperture 15 may adjust the aperture size based on the control of the control unit 18 described later. A region a4 other than the first region a1 in the first aperture 15 may be a region that does not allow electromagnetic waves to pass. Electromagnetic waves other than the electromagnetic waves passing through the first region a1 may be blocked by the first aperture 15.

[0029] The first diaphragm 15 may be disposed at any position on the path along which the electromagnetic wave incident on the incident section 12 travels. For example, the first diaphragm 15 may be disposed on the object side of the incident section 12, within the incident section 12 when the incident section 12 is configured with a plurality of optical elements, or on the image side of the incident section 12. The first diaphragm 15 may be disposed such that the center of gravity of the first region a1 coincides with the optical axis of the incident section 12, regardless of the shape of the first region a1.

[0030] As shown in FIG. 3, the second aperture 16 has a second region a2 and a third region a3 around the second region a2.

[0031] The second region a2 passes electromagnetic waves traveling to the first detection unit 13 and the second detection unit 14. The second region a2 is smaller than the first region a1. More specifically, when the first aperture 15 has a shape having a major axis and a minor axis, such as an ellipse or a rectangle, the minor axis of the first region a1 may be longer than or equal to the diameter of the second region a2. The shape of the second region a2 in the second aperture 16 may be any shape, such as a circle, an ellipse, or a rectangle with rounded corners.

[0032] The third region a3 does not pass electromagnetic waves traveling to the second detection unit 14. The third region a3 may pass electromagnetic waves traveling to the first detection unit 13. The third region a3 does not pass electromagnetic waves in the visible light band, for example, but passes waves reflected by an object that are electromagnetic waves in the infrared band radiated by the irradiation unit 11. The area of ​​the third region a3 may be larger than the area of ​​the first region a1.

[0033] The second aperture 16 may adjust the amount of electromagnetic waves passing through by preventing the electromagnetic waves from traveling to the second detection unit 14 in the third region a3.

[0034] The second region a2 of the second aperture 16 may be a wavelength filter capable of transmitting electromagnetic waves traveling to the first detection unit 13 and the second detection unit 14, such as visible light and reflected waves of electromagnetic waves emitted by the irradiation unit 11 reflected by an object. The third region a3 of the second aperture 16 may be a wavelength filter that blocks transmission of electromagnetic waves traveling to the second detection unit 14, such as visible light, and that can transmit electromagnetic waves in the infrared band, for example, traveling to the first detection unit 13, such as reflected waves of electromagnetic waves emitted by the irradiation unit 11 reflected by an object.

[0035] The second diaphragm 16 may be disposed at any position on the path along which the electromagnetic wave incident on the incident section 12 travels. For example, the second diaphragm 16 may be disposed on the object side of the incident section 12, within the incident section 12 when the incident section 12 is configured with a plurality of optical elements, or on the image side of the incident section 12. In this embodiment, the second diaphragm 16 is disposed on the object side of the incident section 12. The second diaphragm 16 may be disposed such that the centers of gravity of the second region a2 and the third region a3 coincide with the center of the optical axis, regardless of the shape of the second region a2.

[0036] As shown in FIG. 1, the optical system 17 guides a first portion of the electromagnetic waves that have passed through the first aperture 15 and the second aperture 16 to the first detection unit 13. The first portion is a component that includes at least a reflected wave. The optical system 17 guides a second portion of the electromagnetic waves that have passed through the first aperture 15 and the second aperture 16 to the second detection unit 14. The second portion is a portion of the electromagnetic waves that have passed through the first aperture 15 and the second aperture 16 excluding the first portion. For example, the first portion may be electromagnetic waves in the infrared band, and the second portion may be electromagnetic waves in the visible light band.

[0037] The optical system 17 may have a separation unit 21 that guides the first portion to the first detection unit 13 and the second portion to the second detection unit 14. The separation unit 21 may be provided on a path along which the electromagnetic wave that has passed through the entrance unit 12 travels.

[0038] The separation unit 21 may be provided between the incident unit 12 and a primary imaging position, which is an imaging position by the incident unit 12 of an image of an object ob that is a predetermined position away from the incident unit 12. The separation unit 21 may separate the incident electromagnetic wave so that it travels in a first direction d1 and a second direction d2.

[0039] A first detection unit 13 may be provided in a first direction d1 relative to the separation unit 21. Alternatively, as described below, a switching unit 22 capable of causing an electromagnetic wave to travel to the first detection unit 13 may be provided in the first direction d1 relative to the separation unit 21. A second detection unit 14 may be provided in a second direction d2 relative to the separation unit 21.

[0040] More specifically, in this embodiment, the separation unit 21 transmits a first portion of the incident electromagnetic wave in a first direction d1 and reflects a second portion in a second direction d2. The separation unit 21 may transmit a first portion of the incident electromagnetic wave in the first direction d1 and transmit a second portion of the electromagnetic wave in the second direction d2. The separation unit 21 may also refract a part of the incident electromagnetic wave in the first direction d1 and refract another part of the electromagnetic wave in the second direction d2. The separation unit 21 is, for example, a half mirror, a beam splitter, a dichroic mirror, a cold mirror, a hot mirror, a metasurface, a deflection element, a prism, or the like. In this embodiment, the separation unit 21 is configured by sandwiching a wavelength selection filter between two prisms.

[0041] The optical system 17 may further include a switching unit 22. As described above, the switching unit 22 may be provided in the first direction d1 with respect to the separation unit 21. The switching unit 22 may be provided at a primary imaging position or in the vicinity of the primary imaging position by the incident unit 12 in the first direction d1 from the separation unit 21 of an image of an object ob separated at a predetermined position from the incident unit 12.

[0042] The switching unit 22 may have an action surface as on which a first portion of the electromagnetic wave that has passed through the entrance unit 12 and the separation unit 21 is incident. The action surface as may be composed of a plurality of switching elements se arranged two-dimensionally. The action surface as is a surface that causes an action, such as reflection or transmission, on the electromagnetic wave in at least one of a first state and a second state described below.

[0043] The switching unit 22 may be capable of switching between a first state in which the electromagnetic wave incident on the action surface as travels in a third direction d3 and a second state in which the electromagnetic wave travels in a fourth direction d4 for each switching element se. More specifically, the switching unit 22 may include a reflective surface that reflects the electromagnetic wave for each switching element se. The switching unit 22 may switch between the first state and the second state for each switching element se by changing the orientation of the reflective surface for each switching element se.

[0044] The first detector 13 may be provided on a path of the electromagnetic wave traveling in the third direction d3 relative to the switching unit 22. Specifically, the first detector 13 may be provided in the third direction d3 relative to the switching unit 22. Or, the first detector 13 may be provided in a reflection direction by a reflecting surface located in the third direction d3 relative to the switching unit 22. For example, the electromagnetic wave reflected in the third direction d3 by the switching unit 22 may be totally reflected at an interface of a prism constituting the separation unit 21 of the above-mentioned configuration. In such a configuration, the first detector 13 is provided in a reflection direction from the interface.

[0045] Since the first detection unit 13 is disposed as described above, in the first state, the switching element se causes the first portion of the electromagnetic wave to travel to the first detection unit 13. In addition, in the second state, the switching element se blocks the first portion of the electromagnetic wave from traveling to the first detection unit 13 and does not allow it to travel.

[0046] The switching unit 22 may include, for example, a DMD (Digital Micromirror Device). The DMD can switch the inclination of the reflection surface of each switching element se to either +12° or 12° with respect to the action surface as by driving a minute reflection surface that constitutes the action surface as. The action surface as may be parallel to the plate surface of a substrate on which the minute reflection surface of the DMD is placed.

[0047] The switching unit 22 may switch between the first state and the second state for each switching element se based on the control of the control unit 18 described later. For example, as shown in Fig. 4, the switching unit 22 can simultaneously switch some switching elements se1 to the first state to cause the electromagnetic wave incident on the switching elements se1 to travel in the third direction d3, and can simultaneously switch some switching elements se2 to the second state to cause the electromagnetic wave incident on the switching elements se2 to travel in the fourth direction d4.

[0048] A secondary imaging optical system 23 may be provided between the first detection unit 13 and the switching unit 22. The secondary imaging optical system 19 may include, for example, at least one of a lens and a mirror. The secondary imaging optical system 23 may form an image of the object ob as an electromagnetic wave whose traveling direction has been switched by the switching unit 22.

[0049] In addition, in the configuration in which the first detection unit 13 is a single element constituting the distance measuring sensor described above, it is sufficient that the first detection unit 13 can detect electromagnetic waves, and it is not necessary that an image of an object is formed on the detection surface. Therefore, the first detection unit 13 does not need to be provided at the secondary imaging position, which is the imaging position by the secondary imaging optical system 23. In other words, in this configuration, the first detection unit 13 may be located anywhere on the path of the electromagnetic wave that travels through the secondary imaging optical system 23 after traveling in the third direction d3 by the switching unit 22, as long as the first detection unit 13 is located at a position where electromagnetic waves from all angles of view can be incident on the detection surface.

[0050] The control unit 18 includes one or more processors and a memory. The processor may include at least one of a general-purpose processor that loads a specific program to execute a specific function and a dedicated processor specialized for a specific process. The dedicated processor may include an application specific integrated circuit (ASIC). The processor may include a programmable logic device (PLD). The PLD may include a field-programmable gate array (FPGA). The control unit 18 may include at least one of a system-on-a-chip (SoC) and a system in a package (SiP) in which one or more processors work together.

[0051] The control unit 18 acquires first spatial information about the space into which the irradiation unit 11 radiates the electromagnetic waves, based on the detection of the electromagnetic waves by the first detection unit 13. Moreover, the control unit 18 acquires second spatial information about the space, based on the detection of the electromagnetic waves by the second detection unit 14.

[0052] The resolution of the first spatial information is lower than the resolution of the second spatial information. Here, the resolution refers to the density of information acquired by the first detection unit 13 and the second detection unit 14 from the space into which the irradiation unit 11 radiates the electromagnetic waves. More specifically, for example, the distance information acquired by the first detection unit 13 may be distance information for each region corresponding to a plurality of pixels adjacent to each other in the image information acquired by the second detection unit 14. The first spatial information and the second spatial information may be, for example, image information, distance information, and temperature information. In this embodiment, the control unit 18 may acquire the distance information by measuring the distance of an object located in the radiation direction of the irradiation unit 11 based on the detection information detected by the first detection unit 13. More specifically, the control unit 18 may generate the distance information by a Time-of-Flight (ToF) method, as described later. In this embodiment, the control unit 18 acquires the electromagnetic waves detected by the second detection unit 14 as image information. Furthermore, in this embodiment, the control unit 18 can calculate the radiation direction based on a drive signal input to the reflection unit 20 to cause the reflection unit 20 to change the direction in which the electromagnetic wave is reflected.

[0053] As shown in FIG. 5, the control unit 18 may input an electromagnetic wave radiation signal to the light source unit 19 in the irradiation unit 11 to cause the light source unit 19 to radiate a pulsed electromagnetic wave (see the "Electromagnetic Wave Radiation Signal" column). The light source unit 19 may radiate an electromagnetic wave based on the input electromagnetic wave radiation signal (see the "Radiation Amount of Irradiation Unit" column). The electromagnetic wave radiated by the light source unit 19 and reflected by the reflection unit 20 to radiate an arbitrary irradiation area is reflected in the irradiation area. The control unit 18 may switch at least a part of the switching elements se in the imaging area in the switching unit 22 by the incidence unit 12 of the reflected wave from the irradiation area to a first state, and switch the other switching elements se to a second state. The switching of the switching elements se may be performed prior to the radiation of the electromagnetic wave by the irradiation unit 11. The control unit 18 may switch the switching element se corresponding to the next radiation direction of the electromagnetic wave by the reflection unit 20 to a first state every time the irradiation unit 11 radiates a pulsed electromagnetic wave. That is, the control unit 18 may switch at least some of the switching elements se in the imaging area in the switching unit 22 for the reflected wave of the electromagnetic wave next radiated from the irradiation unit 11 to the first state and switch the other switching elements se to the second state. When the first detection unit 13 detects the electromagnetic wave reflected in the irradiation area (see the "Detected amount of electromagnetic wave" column), it notifies the control unit 18 of the detection information as described above.

[0054] The control unit 18 may have a time measurement LSI (Large Scale Integrated circuit). The control unit 18 may measure a time ΔT from a time T1 when the irradiating unit 11 radiates an electromagnetic wave to a time T2 when the detection information is acquired (see the "Acquisition of Detection Information" section). The control unit 18 may calculate the distance to the irradiation position by multiplying the time ΔT by the speed of light and dividing by 2. Note that the control unit 18 may calculate the irradiation position based on the drive signal output to the reflecting unit 20 as described above. The control unit 18 may create image-like distance information by calculating the distance to each irradiation position corresponding to the radiation direction while changing the radiation direction.

[0055] As described above, the electromagnetic wave detection device 10 is configured to generate distance information by Direct ToF, which irradiates a laser beam and directly measures the time it takes for the beam to return, but is not limited to such a configuration. For example, the electromagnetic wave detection device 10 may generate distance information by Flash ToF, which irradiates an electromagnetic wave at a constant cycle and indirectly measures the time it takes for the beam to return from the phase difference between the irradiated electromagnetic wave and the returned electromagnetic wave. The electromagnetic wave detection device 10 may also generate distance information by other ToF methods, such as Phased ToF.

[0056] In a configuration in which the first aperture 15 is a variable aperture, the control unit 18 may control the first aperture 15 to adjust the opening amount of the first aperture 15. By adjusting the opening amount of the first aperture 15, the depth of field of the first detection unit 13 can be appropriately adjusted. The control unit 18 may adjust the opening amount of the first aperture 15 according to the resolution required for the first spatial information acquired by the first detection unit 13. The control unit 18 may receive an input of the resolution required for the first spatial information. In accordance with the adjustment of the opening amount, the control unit 18 may control the switching unit 22 to change the number of switching elements se switched to the first state according to the adjusted opening amount. More specifically, the control unit 18 may control the switching unit 22 to increase the number of switching elements se switched to the first state according to the opening amount. In such a configuration, the control unit 18 may increase the number of switching elements se switched to the first state as the opening amount of the first aperture 15 increases. Similarly, the control unit 18 may reduce the number of switching elements se switched to the first state as the opening amount of the first diaphragm 15 becomes smaller. The switching elements se switched to the first state may be a group of switching elements se centered on a switching element se corresponding to a point in the irradiation area.

[0057] 6, the electromagnetic wave detection device 10 may be mounted on a moving object 24. The electromagnetic wave detection device 10 may be installed so as to be able to detect electromagnetic waves in front of the moving object 24, for example.

[0058] The moving body 24 may include, for example, a vehicle, a ship, an aircraft, and the like. The vehicle may include, for example, an automobile, an industrial vehicle, a railroad vehicle, a vehicle for daily life, a fixed-wing aircraft traveling on a runway, and the like. The automobile may include, for example, a passenger car, a truck, a bus, a motorcycle, a trolley bus, and the like. The industrial vehicle may include, for example, an industrial vehicle for agriculture or construction, and the like. The industrial vehicle may include, for example, a forklift, a golf cart, and the like. The industrial vehicle for agriculture may include, for example, a tractor, a cultivator, a transplanter, a binder, a combine, a lawnmower, and the like. The industrial vehicle for construction may include, for example, a bulldozer, a scraper, a shovel, a crane, a dump truck, a road roller, and the like. The vehicle may include one that runs by human power. The classification of the vehicle is not limited to the above-mentioned examples. For example, the automobile may include an industrial vehicle that can run on a road. The same vehicle may be included in multiple classifications. The ship may include, for example, a marine jet, a boat, and a tanker. Aircraft may include, for example, fixed wing aircraft, rotorcraft, etc.

[0059] The electromagnetic wave detection device 10 may be mounted, for example, inside the mobile object 24 and detect electromagnetic waves incident from the outside of the mobile object 24 through the windshield. The electromagnetic wave detection device 10 may be disposed in front of the rearview mirror or on the dashboard. The electromagnetic wave detection device 10 may be fixed to any of the front bumper, fender grille, side fender, light module, and bonnet of the mobile object 24.

[0060] Next, the aperture adjustment process executed by the control unit 18 in this embodiment will be described with reference to the flowchart in Fig. 7. The aperture adjustment process starts when it is determined to adjust the aperture size. The aperture size adjustment may be determined based on an adjustment input to a detection unit that detects a user input or a determination by the control unit 18 based on various information.

[0061] In step S100, the control unit 18 determines whether the opening amount determined to be adjusted is increased or decreased from the current opening amount. If it is increased, the process proceeds to step S101. If it is decreased, the process proceeds to step S102.

[0062] In step S101, the control unit 18 determines to increase the number of switching elements se that are switched to the first state. After the determination, the process proceeds to step S103.

[0063] In step S102, the control unit 18 determines to reduce the number of switching elements se that are switched to the first state. After the determination, the process proceeds to step S103.

[0064] In step S103, the control unit 18 controls the first diaphragm 15 so as to adjust the aperture amount to the determined amount, and starts control to switch the switching elements se to the first state in the number determined in step S101 or step S102. After controlling the first diaphragm 15 and the switching unit 22, the aperture adjustment process ends.

[0065] The electromagnetic wave detection device 10 of the present embodiment configured as described above includes a first aperture 15 having a first region a1 that passes electromagnetic waves traveling to the first detection unit 13 and the second detection unit 14, a second aperture 16 having a second region a2 that passes electromagnetic waves traveling to the first detection unit 13 and the second detection unit 14 and is smaller than the first region a1, and a third region a3 around the second region a2 that does not pass electromagnetic waves traveling to the second detection unit 14, and a control unit 18 that acquires first spatial information about the space based on the detection of the electromagnetic waves by the first detection unit 13 and acquires second spatial information about the space based on the detection of the electromagnetic waves by the second detection unit 14, and the resolution of the first spatial information is lower than the resolution of the second spatial information. In an optical system that forms an image of an electromagnetic wave, when the aperture is widened, the amount of electromagnetic waves passing through the optical system increases while the depth of field becomes shallow. To cope with such an event, the electromagnetic wave detection device 10 having the above-mentioned configuration can adjust the amount of electromagnetic waves reaching the first detection unit 13 by using the first aperture 15, which has a wider passable area than the second aperture 16. Therefore, the electromagnetic wave detection device 10 can increase the amount of electromagnetic waves reaching the first detection unit 13 while deepening the depth of field for the second detection unit 14 by using the second aperture 16. As a result, the electromagnetic wave detection device 10 can provide the entrance unit 12 shared by multiple detectors, such as the first detection unit 13 and the second detection unit 14, with optical characteristics suitable for each detector.

[0066] In addition, in the electromagnetic wave detection device 10 of this embodiment, the first region a1 of the first aperture 15 has a major axis in a direction intersecting with the arrangement direction of the irradiation unit 11 and the incident unit 12. As described above, in the electromagnetic wave detection device 10, in a configuration in which the position where the electromagnetic wave is radiated to the object ob is different from the position where the electromagnetic wave is incident on the incident unit 12, in order to improve the positional accuracy of the detection result of the first detection unit 13, it is required to bring the irradiation unit 11 and the incident unit 12 close to each other. On the other hand, the first region a1 needs a predetermined size to allow the electromagnetic wave to be incident. If the first region a1 is made, for example, a perfect circle or a square, it becomes difficult to bring the irradiation unit 11 and the incident unit 12 close to each other in the arrangement direction in order to avoid interference with the incident unit 12 and the first aperture 15. In response to such a situation, the electromagnetic wave detection device 10 having the above-described configuration can allow a sufficient amount of electromagnetic waves to reach the first detection unit 13 even if the first region a1 is set to the short diameter in the arrangement direction of the irradiation unit 11 and the incident unit 12, so that the irradiation unit 11 and the incident unit 12 can be brought close to each other. Therefore, the electromagnetic wave detection device 10 improves the positional accuracy of the detection result of the first detection unit 13. The irradiation unit 11 and the incident unit 12 may be arranged so that the optical axis center of the irradiation unit 11 and the optical axis center of the incident unit 12 are aligned in the vertical or horizontal direction. This arrangement can reduce the deviation between the irradiation direction of the electromagnetic wave radiated by the irradiation unit 11 and the angle of view of the incident unit 12, and can widen the range in which the first spatial information is acquired.

[0067] In the electromagnetic wave detection device 10 of this embodiment, the second aperture 16 is disposed closer to the object side than the incident portion 12. As described above, the second aperture 16 having the third region a3 that does not transmit the electromagnetic wave to be advanced to the second detection portion 14 and transmits the electromagnetic wave to be advanced to the first detection portion 15 is formed to be thicker than the first aperture 15. More specifically, the thicknesses of the second region a2 and the third region a3 are greater than the thickness of the first region a1. As shown in FIG. 4, the thicker the aperture, the more likely it is that the electromagnetic wave will be reflected at the inner peripheral surface ips of the aperture. Therefore, if a relatively thick aperture is disposed inside the incident portion 12, the reflected wave at the inner peripheral surface of the aperture may become noise. In response to such an event, the electromagnetic wave detection device 10 having the above-described configuration reduces the possibility of the reflected wave, which causes noise, entering the optical system 17, and therefore may reduce noise.

[0068] Furthermore, the electromagnetic wave detection device 10 of this embodiment can switch some of the switching elements se in the switching unit 22 to a first state, and switch other some of the switching elements se to a second state. With this configuration, the electromagnetic wave detection device 10 can cause the first detection unit 13 to detect information based on the electromagnetic waves for each part of the target ob that emits the electromagnetic waves incident on each switching element se. Therefore, the electromagnetic wave detection device 10 prevents the electromagnetic waves emitted by the irradiation unit 11 from reaching the first detection unit 13 at a position other than the irradiation position of the electromagnetic waves. As a result, the electromagnetic wave detection device 10 can improve the detection accuracy of the reflected wave at the irradiation position.

[0069] Furthermore, the electromagnetic wave detection device 10 of this embodiment changes the number of switching elements se that are switched to the first state according to the opening size of the first diaphragm 15. The spread of the spot of the electromagnetic wave that is imaged on the action surface as of the switching unit 22 changes according to the opening size of the first diaphragm 15. In response to such an event, the electromagnetic wave detection device 10 having the above-mentioned configuration can switch the switching elements se to the first state according to the spread of the spot. Therefore, the electromagnetic wave detection device 10 can suppress a decrease in the amount of the reflected wave in the irradiation area that reaches the first detection unit 13.

[0070] Although the embodiments according to the present disclosure have been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various modifications or corrections based on the present disclosure. Therefore, it should be noted that these modifications or corrections are included in the scope of the present disclosure. For example, the functions included in each component or each step can be rearranged so as not to be logically contradictory, and multiple components or steps can be combined into one or divided. Although the embodiments according to the present disclosure have been described mainly with respect to the device, the embodiments according to the present disclosure can also be realized as a method including steps executed by each component of the device. The embodiments according to the present disclosure can also be realized as a method, a program, or a storage medium on which a program is recorded, executed by a processor provided in the device. It should be understood that these are also included in the scope of the present disclosure.

[0071] For example, in the switching unit 22 of this embodiment, in the first state, electromagnetic waves incident on the action surface as are reflected in the third direction d3, and in the second state, electromagnetic waves incident on the action surface as are reflected in the fourth direction d4, but other configurations may be adopted.

[0072] 8, the switching unit 220 may transmit the electromagnetic wave incident on the action surface as in the first state to cause the electromagnetic wave to travel in the third direction d3. More specifically, the switching unit 220 may include a shutter having a reflecting surface that reflects the electromagnetic wave in a fourth direction for each switching element. In the switching unit 220 configured in this way, the traveling direction of the electromagnetic wave can be switched between the third direction d3 and the fourth direction d4 for each switching element by opening and closing the shutter for each switching element.

[0073] An example of the switching unit 220 having such a configuration is a switching unit including a MEMS shutter in which a plurality of openable and closable shutters are arranged in an array. Also, an example of the switching unit 220 is a switching unit including a liquid crystal shutter that can switch between a reflective state that reflects electromagnetic waves and a transmissive state that transmits electromagnetic waves in accordance with the liquid crystal orientation.

[0074] Furthermore, in this embodiment, the electromagnetic wave detection device 10 has a configuration in which the reflecting unit 20 is caused to scan the beam-shaped electromagnetic waves emitted from the irradiating unit 11, thereby causing the first detecting unit 13 to function as a scanning-type active sensor in cooperation with the reflecting unit 20. However, the electromagnetic wave detection device 10 is not limited to this configuration. For example, even if the electromagnetic wave detection device 10 does not include the reflecting unit 20 and is caused to irradiate radial electromagnetic waves from the irradiating unit 11 and acquire information without scanning, an effect similar to that of this embodiment can be obtained.

[0075] In this disclosure, descriptions such as "first" and "second" are identifiers for distinguishing the configuration. Configurations distinguished by descriptions such as "first" and "second" in this disclosure may have their numbers exchanged. For example, the first detection unit may exchange identifiers "first" and "second" with the second detection unit. The exchange of identifiers is performed simultaneously. The configurations remain distinguished even after the exchange of identifiers. Identifiers may be deleted. A configuration from which an identifier has been deleted is distinguished by a code. Descriptions of identifiers such as "first" and "second" in this disclosure should not be used solely to interpret the order of the configurations or to justify the existence of an identifier with a smaller number. [Explanation of symbols]

[0076] 10. Electromagnetic wave detection device 11 Irradiation unit 12 Input part 13 First detection unit 14 Second detector 15 First Aperture 16 Second Aperture 17 Optical system 18 Control Unit 19 Light source section 20 Reflector 21 Separation part 22 Switching section 23 Secondary imaging optical system 24 Mobile as action surface a1 First area a2 Second area a3 The third area a4 Area other than the first area in the first aperture d1 First direction d2 Second direction d3 Third direction d4 Fourth direction ips inner surface ob target se switching element

Claims

1. An irradiation unit that radiates electromagnetic waves into space; an incident section into which electromagnetic waves including a reflected wave of the electromagnetic wave radiated by the irradiation section and reflected by a target are incident; a first detection unit that detects a reflected wave incident from the incident unit; A second detection unit that detects the electromagnetic wave incident from the incident unit; a first aperture having a first region that passes electromagnetic waves traveling to the first detection unit and the second detection unit; a second aperture having a second region that passes electromagnetic waves traveling to the first detection unit and the second detection unit and is smaller than the first region, and a third region around the second region that does not pass electromagnetic waves traveling to the second detection unit; an optical system that guides a first portion of the electromagnetic wave that has passed through the first aperture and the second aperture, the first portion including the reflected wave, to the first detection unit, and guides a second portion excluding the first portion to the second detection unit; a control unit that acquires first spatial information about the space based on detection of electromagnetic waves by the first detection unit, and acquires second spatial information about the space based on detection of electromagnetic waves by the second detection unit, the first aperture and the first region have a minor axis in a direction in which the irradiation unit is disposed relative to the incident unit, and a major axis in a direction intersecting the direction in which the irradiation unit is disposed; a resolution of the first spatial information is lower than a resolution of the second spatial information; the second region includes a wavelength filter that passes electromagnetic waves in a band including the wavelength of the electromagnetic waves emitted by the irradiation unit and electromagnetic waves in a visible light band; The third region includes a wavelength filter that passes electromagnetic waves in a band including the wavelength of the electromagnetic waves emitted by the irradiation unit and blocks electromagnetic waves in a visible light band. Electromagnetic wave detection device.

2. 2. The electromagnetic wave detection device according to claim 1, The second region is a circle having a diameter shorter than the minor diameter of the first region. Electromagnetic wave detection device.

3. 3. The electromagnetic wave detection device according to claim 1, The thickness of the second aperture is greater than the thickness of the first aperture, The second aperture is disposed on the object side of the incident portion. Electromagnetic wave detection device.

4. 4. The electromagnetic wave detection device according to claim 1, the optical system has a switching unit including a switching element capable of switching between a first state in which the first portion is caused to proceed to the first detection unit and a second state in which the first portion is not caused to proceed to the first detection unit; The control unit switches a part of the switching elements including at least the reflected wave in an imaging area of ​​the first portion of the switching unit to a first state and switches the other switching elements to the second state prior to the emission of the electromagnetic wave by the irradiation unit. Electromagnetic wave detection device.

5. 5. The electromagnetic wave detection device according to claim 4, The opening amount of the first diaphragm is variable, The number of the switching elements that are switched to the first state is changed according to the opening amount of the first diaphragm. Electromagnetic wave detection device.

6. 6. The electromagnetic wave detection device according to claim 5, The control unit determines an aperture amount of the first diaphragm in accordance with a resolution of the input first spatial information. Electromagnetic wave detection device.

7. 7. The electromagnetic wave detection device according to claim 1, the first spatial information is distance information, The second spatial information is image information. Electromagnetic wave detection device.

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