Sensor Device

Abstract

To correct a deviation from a detection result of a design status of a detection result by a detection unit about a deflection angle of a movable reflection unit.SOLUTION: Some of electromagnetic waves being emitted from an emission unit (110) and being reflected by a movable reflection unit (120) are reflected or scattered by a target object such as an object existing outside a sensor device (10). Some other of the electromagnetic waves being emitted by the emission unit (110) and being reflected by the movable reflection unit (120) are reflected or scattered by a structure (200) positioned closer to the movable reflection unit (120) than the target object. A detection unit (122) detects deflection angles of the movable reflection unit (120) in a first direction (X) and a second direction (Y). An amendment unit (150) amends a detection result by the detection unit (122), based on a receiving result of the electromagnetic waves by a receiving unit (130), the electromagnetic waves being reflected or scattered by the structure (200).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a sensor device. [Background technology]

[0002] In recent years, various sensor devices such as LiDAR (Light Detection and Ranging) have been developed. The sensor devices include a movable reflector such as a MEMS (Micro Electro Mechanical Systems) mirror. The sensor devices scan targets such as objects outside the sensor device by reflecting electromagnetic waves such as infrared rays toward a predetermined scanning range using the movable reflector.

[0003] Patent Document 1 describes that a reflecting member is disposed on one end side of the scanning range of a movable reflecting member in order to determine the direction in which laser light reflected by the movable reflecting member is output. The laser light reflected by the reflecting member is received by a light receiving unit. Based on the light receiving result from the light receiving unit, the distance from the movable reflecting member to the reflecting member is calculated. Based on the distance from the movable reflecting member to the reflecting member, the direction in which laser light reflected by the movable reflecting member is output is calculated.

[0004] Patent document 2 describes a method in which a reflective member is provided in a housing that houses components that constitute a sensor device, such as a movable reflecting member, and the deviation of the scanning position of the movable reflecting member is detected by laser light reflected by the reflective member. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-6403 [Patent Document 2] Japanese Patent Publication No. 2020-16481 Summary of the Invention [Problem to be solved by the invention]

[0006] The sensor device may be provided with a detection unit for detecting the deflection angle of the movable reflector. However, the sensitivity of the detection unit may be temperature-dependent. In this case, the detection result of the detection unit may deviate from the detection result in the designed state.

[0007] One example of a problem to be solved by the present invention is to correct a deviation of the detection result of the deflection angle of the movable reflecting part by the detection part from the detection result of the designed state. [Means for solving the problem]

[0008] The first invention is a movable reflecting unit that reflects electromagnetic waves toward a predetermined scanning range; a detection unit that detects a deflection angle of the movable reflecting unit; a receiving unit that receives the electromagnetic waves reflected or scattered by structures located within the scanning range; a correction unit that corrects a detection result of the detection unit based on a reception result of the electromagnetic wave reflected by the structure by the reception unit; The sensor device is provided with: [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating a sensor device according to an embodiment. [Figure 2] 10A and 10B are diagrams illustrating an example of the relationship between a structure, a scanning line of a movable reflecting portion, and a spot irradiated onto the scanning line. [Figure 3] 3 is a graph showing an example of signals generated in a receiving section by the first spot and the second spot shown in FIG. 2. [Figure 4] 10 is a graph showing an example of changes in the received value of the signal generated in the receiving unit by the first spot and the received value of the signal generated in the receiving unit by the second spot when the deflection angle of the movable reflecting unit in the second direction varies. [Figure 5] 5 is a graph showing the difference between the two received values ​​shown in FIG. 4. [Figure 6] 10 is a graph showing an example of changes in the received value of the signal generated in the receiving unit by the third spot and the received value of the signal generated in the receiving unit by the fourth spot when the deflection angle of the movable reflecting unit in the first direction varies. [Figure 7] 7 is a graph showing the difference between the two received values ​​shown in FIG. 6. [Figure 8] 10A and 10B are diagrams illustrating an example of the relationship between the structure, the scanning line of the movable reflecting portion, and the spot irradiated onto the scanning line in a sensor device according to a modified example. [Figure 9] 10 is a graph showing an example of changes in the received value of the signal generated in the receiving unit by the 9th spot and the received value of the signal generated in the receiving unit by the 10th spot when the deflection angle of the movable reflecting unit in the first direction varies. [Figure 10] 10 is a graph showing the difference between the two received values ​​shown in FIG. 9. [Figure 11] FIG. 10 is a diagram showing an example of the relationship between a structure, a ninth spot, and a tenth spot in a reference state. [Figure 12] FIG. 10 is a diagram showing an example of the relationship between the structure, the ninth spot, and the tenth spot when the deflection angle of the movable reflecting part in the first direction is smaller than the deflection angle in the reference state. [Figure 13] 10 is a diagram showing an example of the relationship between the structure, the ninth spot, and the tenth spot when the deflection angle of the movable reflecting part in the first direction becomes larger than the deflection angle in the reference state. FIG. [Figure 14] 10 is a graph showing an example of the relationship between the deflection angle of the movable reflecting part in the second direction and the difference between the received value of the signal generated in the receiving part by the 11th spot and the received value of the signal generated in the receiving part by the 12th spot. [Figure 15] FIG. 10 is a diagram showing an example of the relationship between a structure and a ninth spot, a tenth spot, an eleventh spot, and a twelfth spot in a reference state. [Figure 16]FIG. 10 is a diagram showing an example of the relationship between the structure and the 9th, 10th, 11th, and 12th spots when the deflection angle of the movable reflecting part in the second direction becomes smaller than the deflection angle in the reference state. [Figure 17] FIG. 10 is a diagram showing an example of the relationship between the structure and the 9th, 10th, 11th, and 12th spots when the deflection angle of the movable reflecting part in the first direction becomes larger than the deflection angle in the reference state. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, like components are designated by like reference numerals, and the description thereof will be omitted as appropriate.

[0011] FIG. 1 is a diagram showing a sensor device 10 according to an embodiment.

[0012] In FIG. 1, the first direction X and the second direction Y intersect with each other, specifically, are perpendicular to each other. In FIG. 1, the first direction X is the horizontal direction. The positive direction of the first direction X, which is the direction of the arrow indicating the first direction X, is the leftward direction when viewed from the movable reflector 120, which will be described later, toward the scanning range of the movable reflector 120, which will be described later. The negative direction of the first direction X, which is the opposite direction to the direction of the arrow indicating the first direction X, is the rightward direction when viewed from the side where the movable reflector 120 is located toward the scanning range of the movable reflector 120. The second direction Y is the vertical direction. The positive direction of the second direction Y, which is the direction of the arrow indicating the second direction Y, is the upward direction. The negative direction of the second direction Y, which is the opposite direction to the direction of the arrow indicating the second direction Y, is the downward direction.

[0013] As is clear from the description herein, the first direction X may be a direction different from the horizontal direction, and the second direction Y may be a direction different from the vertical direction.

[0014] The sensor device 10 includes a light emitting unit 110, a movable reflecting unit 120, a detecting unit 122, a receiving unit 130, a beam splitter 140, a correcting unit 150, a first adjusting unit 162, and a second adjusting unit 164. In Fig. 1, the dotted lines extending from the light emitting unit 110, the movable reflecting unit 120, the receiving unit 130, the beam splitter 140, and the scanning line L indicate electromagnetic waves propagating from the light emitting unit 110, the movable reflecting unit 120, the receiving unit 130, the beam splitter 140, and the scanning line L. In Fig. 1, the electromagnetic waves reflected from the movable reflecting unit 120 toward the scanning line L are irradiated toward approximately the center of the area where the scanning line L is formed.

[0015] The emission unit 110 emits pulsed electromagnetic waves such as infrared rays at regular intervals. The emission unit 110 is an element, such as a laser diode (LD), that can convert electricity such as current into electromagnetic waves such as light. The electromagnetic waves emitted from the emission unit 110 are reflected by the beam splitter 140 and enter the movable reflector 120.

[0016] The movable reflector 120 reflects the electromagnetic waves emitted from the emission unit 110 toward a predetermined scanning range. The scanning range of the movable reflector 120 is a range that can be irradiated by the electromagnetic waves reflected by the movable reflector 120. The movable reflector 120 is, for example, a two-axis MEMS mirror. The movable reflector 120 is driven in a first direction X, for example, in a sinusoidal wave shape, and in a second direction Y, for example, in a sawtooth wave shape at a frequency lower than the sinusoidal wave in the first direction X. In other words, the first direction X is the direction of resonant driving of the movable reflector 120, and the second direction Y is the direction of linear driving of the movable reflector 120.

[0017] The detection unit 122 detects the deflection angles of the movable reflector 120 in the first direction X and the second direction Y. The detection unit 122 is, for example, a piezoresistance element provided in the movable reflector 120. The deflection angles of the movable reflector 120 in the first direction X and the second direction Y are controlled based on the detection results of the detection unit 122. Therefore, if the sensitivity of the detection unit 122 is temperature dependent, the detection results of the deflection angle of the movable reflector 120 by the detection unit 122 may vary depending on the temperature, and as a result, the deflection angle of the movable reflector 120 may vary depending on the temperature. As will be described later, in this embodiment, the detection results of the deflection angle of the movable reflector 120 by the detection unit 122 can be corrected by the correction unit 150.

[0018] A portion of the electromagnetic waves emitted from the emission unit 110 and reflected by the movable reflection unit 120 is reflected or scattered by an object such as a physical body present outside the sensor device 10. This electromagnetic wave returns to the movable reflection unit 120, is reflected by the movable reflection unit 120, and passes through the beam splitter 140, before entering the reception unit 130 and being received by the reception unit 130. The reception unit 130 is an element, such as an avalanche photodiode (APD), that can convert electromagnetic waves such as light into an electrical signal such as a current.

[0019] Another part of the electromagnetic waves emitted from the emission unit 110 and reflected by the movable reflector 120 is reflected or scattered by the structure 200, which is located closer to the movable reflector 120 than the target object. This electromagnetic wave returns toward the movable reflector 120, is reflected by the movable reflector 120, and passes through the beam splitter 140, before entering the receiving unit 130 and being received by the receiving unit 130. The structure 200 may be made of, for example, a metal that has been subjected to a surface treatment such as plating that provides high stability over time.

[0020] The distance from the movable reflecting unit 120 to the structure 200 is shorter than the distance from the movable reflecting unit 120 to the object. Therefore, the time from the emission of the electromagnetic wave from the emitting unit 110, through its reflection by the structure 200, to its reception by the receiving unit 130 is shorter than the time from the emission of the electromagnetic wave from the emitting unit 110, through its reflection by the object, to its reception by the receiving unit 130. Therefore, based on the time difference between the signals generated in the receiving unit 130, the sensor device 10 can distinguish whether the signal generated in the receiving unit 130 is a signal caused by the structure 200 or a signal caused by the object.

[0021] The sensor device 10 may include a structure 200. Alternatively, the structure 200 may be provided outside the sensor device 10. When the sensor device 10 includes the structure 200, the structure 200 can be provided, for example, in a window portion of a housing that houses components of the sensor device 10, such as the emission unit 110, the movable reflecting unit 120, the receiving unit 130, and the beam splitter 140, i.e., in a portion through which electromagnetic waves pass between the inside and outside of the housing. However, the location where the structure 200 is provided is not limited to the window portion.

[0022] In this embodiment, the correction unit 150, the first adjustment unit 162, and the second adjustment unit 164 represent functional blocks rather than hardware-based configurations. The correction unit 150, the first adjustment unit 162, and the second adjustment unit 164 are realized by any combination of hardware and software, centered around the CPU of any computer, memory, a program loaded into the memory, a storage medium such as a hard disk for storing the program, and a network connection interface. There are various variations in the realization method and device.

[0023] The correction unit 150 corrects the detection result of the detection unit 122 based on the reception result by the receiving unit 130 of the electromagnetic waves reflected or scattered by the structure 200. The correction by the correction unit 150 can correct any deviation of the detection result by the detection unit 122 regarding the deflection angle of the movable reflecting unit 120 from the detection result of the designed state.

[0024] FIG. 2 is a diagram showing an example of the relationship between the structure 200, the scanning line L of the movable reflecting portion 120, and the spot irradiated onto the scanning line L. As shown in FIG.

[0025] In FIG. 2, the scanning line L extends in a first direction X, i.e., the direction of resonant driving of the movable reflector 120, and then in a second direction Y, i.e., from the positive direction to the negative direction of the linear driving direction of the movable reflector 120.

[0026] 2 shows eight spots, namely, a first spot S1, a second spot S2, a third spot S3, a fourth spot S4, a fifth spot S5, a sixth spot S6, a seventh spot S7, and an eighth spot S8, located on the scanning line L. Each spot is generated by an electromagnetic wave emitted from the emission unit 110 and reflected by the movable reflection unit 120 toward the structure 200.

[0027] The first spot S1, the second spot S2, the third spot S3, and the fourth spot S4 are each used for correction by the correction unit 150. At least a portion of each of the first spot S1, the second spot S2, the third spot S3, and the fourth spot S4 is irradiated onto the structure 200. The first spot S1, the second spot S2, the third spot S3, and the fourth spot S4 may be used for sensing by the sensor device 10. The first spot S1 and the second spot S2 are shifted in the direction of linear drive of the movable reflector 120, i.e., the second direction Y. The second spot S2 is located further outward in the second direction Y than the first spot S1 in the region where the scanning line L is formed. The third spot S3 and the fourth spot S4 are shifted in the direction of resonant drive of the movable reflector 120, i.e., the first direction X. The fourth spot S4 is located further outward in the first direction X than the third spot S3 in the region where the scanning line L is formed.

[0028] The fifth spot S5, the sixth spot S6, the seventh spot S7, and the eighth spot S8 are each a part of the spots used for sensing by the sensor device 10. None of the fifth spot S5, the sixth spot S6, the seventh spot S7, and the eighth spot S8 is irradiated onto the structure 200. Therefore, for the fifth spot S5, the sixth spot S6, the seventh spot S7, and the eighth spot S8, the energy of the electromagnetic waves irradiated onto the object is not reduced by the structure 200, and the object can be efficiently sensed. The fifth spot S5 and the sixth spot S6 are shifted to the left with respect to the first spot S1 and the second spot S2, respectively. The seventh spot S7 and the eighth spot S8 are shifted upward with respect to the third spot S3 and the fourth spot S4, respectively.

[0029] The structure 200 is located outside the region where the scanning line L of the movable reflector 120 is formed. If the movable reflector 120 were located inside the region where the scanning line L is formed, the sensor device 10 would be unable to detect an object in the region where the structure 200 is located, or the detection performance would be degraded. In contrast, in the example shown in Fig. 2, the region where the sensor device 10 would be unable to detect an object or where the detection performance would be degraded can be limited to outside the region where the scanning line L of the movable reflector 120 is formed.

[0030] The correction unit 150 can correct the detection result of the detection unit 122 based on the relationship between a first reception value by the reception unit 130 of the electromagnetic wave reflected or scattered by a predetermined first portion of the structure 200 and a second reception value by the reception unit 130 of the electromagnetic wave reflected or scattered by a predetermined second portion of the structure 200. In this case, the correction unit 150 can correct the detection result of the detection unit 122 in accordance with the relationship between the first reception value and the second reception value, for example, at least one of the difference and ratio between the first reception value and the second reception value, and the deviation of the detection result of the detection unit 122 from the detection result in a reference state such as a design state or an initial state.

[0031] The correction unit 150 can correct the detection result of the detection unit 122 based on a comparison result between the relationship between the first reception value and the second reception value, and the relationship between a first reference reception value by the reception unit 130 of the electromagnetic wave reflected or scattered by the first portion of the structure 200 when the detection unit 122 operates in the reference state and a second reference reception value by the reception unit 130 of the electromagnetic wave reflected or scattered by the second portion of the structure 200 when the detection unit 122 operates in the reference state. The relationship between the first reference reception value and the second reference reception value can be a known, predetermined reference relationship. For example, at least one of the difference and the ratio between the first reference reception value and the second reference reception value may be a known, predetermined reference value. In this case, if the sensitivity of the detecting unit 122 varies from the sensitivity when the detecting unit 122 is in the reference state due to certain factors such as temperature, and the deflection angle of the movable reflecting unit 120 varies from the deflection angle when the detecting unit 122 is in the reference state, the relationship between the first received value and the second received value will vary from the predetermined reference relationship. The correcting unit 150 can correct the detection result of the detecting unit 122 so that the relationship between the first received value and the second received value returns to the predetermined reference relationship. The first reference received value and the second reference received value can be made substantially equal to each other, for example.

[0032] In one example, the first portion of the structure 200 may be a region of the structure 200 irradiated with the first spot S1 and its periphery, and the second portion of the structure 200 may be a region of the structure 200 irradiated with the second spot S2 and its periphery. That is, the first and second portions of the structure 200 may be offset from each other in the direction of linear drive of the movable reflector 120, i.e., the second direction Y.

[0033] The first adjustment unit 162 can adjust the position of the structure 200 so that the relationship between the first reference reception value and the second reference reception value satisfies a predetermined reference relationship. For example, the first adjustment unit 162 can move the structure 200 along the second direction Y. This makes it possible to ensure that the relationship between the first reference reception value for the first spot S1 and the second reference reception value for the second spot S2 satisfies a predetermined reference relationship.

[0034] In another example, the first portion of the structure 200 may be a region of the structure 200 irradiated with the third spot S3 and its periphery, and the second portion of the structure 200 may be a region of the structure 200 irradiated with the fourth spot S4 and its periphery. That is, the first and second portions of the structure 200 may be offset from each other in the direction of resonant driving of the movable reflecting unit 120, i.e., the first direction X.

[0035] The second adjustment section 164 can adjust the timing of emitting the electromagnetic wave from the emission section 110 so that the relationship between the first reference reception value and the second reference reception value satisfies a predetermined reference relationship. This makes it possible to ensure that the relationship between the first reference reception value for the third spot S3 and the second reference reception value for the fourth spot S4 satisfies a predetermined reference relationship.

[0036] The adjustment of the position of the structure 200 by the first adjustment unit 162 and the adjustment of the emission timing of the electromagnetic wave from the emission unit 110 by the second adjustment unit 164 can be combined as appropriate. For example, the first adjustment unit 162 may move the structure 200 in the second direction Y to correct the detection result of the detection unit 122 of the deflection angle of the movable reflector 120 in the second direction Y, and the second adjustment unit 164 may adjust the emission unit 110 to correct the detection result of the detection unit 122 of the deflection angle of the movable reflector 120 in the first direction X. In this case, the structure 200 may be fixed so as not to move along the first direction X. Alternatively, the first adjustment unit 162 may move the structure 200 in both the first direction X and the second direction Y to correct the detection result of the detection unit 122 of the deflection angle of the movable reflector 120 in the first direction X and the second direction Y. In this case, the second adjustment unit 164 does not need to adjust the emission unit 110.

[0037] 3 is a graph showing an example of signals generated in the receiving unit 130 by the first spot S1 and the second spot S2 shown in FIG. 2. FIG. 4 is a graph showing an example of changes in the received value S(S1) of the signal generated in the receiving unit 130 by the first spot S1 and the received value S(S2) of the signal generated in the receiving unit 130 by the second spot S2 when the deflection angle of the movable reflecting unit 120 in the second direction Y varies. FIG. 5 is a graph showing the difference S(S1)-S(S2) between the two received values ​​S(S1) and S(S2) shown in FIG. 4. FIG. 6 is a graph showing an example of changes in the received value S(S3) of the signal generated in the receiving unit 130 by the third spot S3 and the received value S(S4) of the signal generated in the receiving unit 130 by the fourth spot S4 when the deflection angle of the movable reflecting unit 120 in the first direction X varies. FIG. 7 is a graph showing the difference S(S3)-S(S4) between the two received values ​​S(S3) and S(S4) shown in FIG.

[0038] In Fig. 3, the signal with peak value a indicates the signal generated by the first spot S1. Furthermore, the signal with peak value b indicates the signal generated by the second spot S2. The received values ​​S(S1), S(S2), S(S3), S(S4), etc. in Figs. 4 to 6 of the signals generated in the receiving unit 130 by each spot are the peak values ​​a, b, etc. in Fig. 3 of the signals generated in the receiving unit 130 by each spot.

[0039] The horizontal axis of the graph in FIG. 4 represents the deflection angle of the movable reflector 120 in the second direction Y. The vertical axis of the graph in FIG. 4 represents the intensity of each of the two received values ​​S(S1) and S(S2). The solid line marked with "PY" represents the deflection angle of the movable reflector 120 in the second direction Y in the reference state. For example, in the example shown in FIG. 2, when the movable reflector 120 deflects significantly in the second direction Y, the first spot S1 and the second spot S2 move outward, the area of ​​the first spot S1 irradiated onto the structure 200 decreases, and the received value S(S1) decreases, whereas the area of ​​the second spot S2 irradiated onto the structure 200 increases, and the received value S(S2) increases. Therefore, the received values ​​S(S1) and S(S2) change as shown in the graph in FIG. 4 according to the change in the deflection angle of the movable reflector 120 in the second direction Y.

[0040] The horizontal axis of the graph in Fig. 5 represents the deflection angle of the movable reflector 120 in the second direction Y. The vertical axis of the graph in Fig. 5 represents the difference between the two received values ​​S(S1) and S(S2). The solid line marked "PY" represents the deflection angle of the movable reflector 120 in the second direction Y in the reference state.

[0041] The horizontal axis of the graph in FIG. 6 represents the deflection angle of the movable reflector 120 in the first direction X. The vertical axis of the graph in FIG. 6 represents the intensity of each of the two received values ​​S(S3) and S(S4). The solid line marked with "PX" represents the deflection angle of the movable reflector 120 in the first direction X in the reference state. The larger the value on the horizontal axis, the greater the deflection of the movable reflector 120 in the first direction X. For example, in the example shown in FIG. 2, when the movable reflector 120 deflects significantly in the first direction X, the third spot S3 and the fourth spot S4 move outward, the area of ​​the third spot S3 that is irradiated onto the structure 200 decreases, and the received value S(S3) decreases, while the area of ​​the fourth spot S4 that is irradiated onto the structure 200 increases, and the received value S(S4) increases. Therefore, the received values ​​S(S3) and S(S4) change as shown in the graph in FIG. 6 according to the change in the deflection angle of the movable reflector 120 in the first direction X.

[0042] The horizontal axis of the graph in Fig. 7 represents the deflection angle of the movable reflector 120 in the first direction X. The vertical axis of the graph in Fig. 7 represents the difference between the two received values ​​S(S3) and S(S4). The solid line marked with "PX" represents the deflection angle of the movable reflector 120 in the first direction X in the reference state.

[0043] For example, the difference between the first reference reception value for the first spot S1 and the second reference reception value for the second spot S2 can be set to zero. For example, in FIGS. 4 and 5, the first reference reception value is the reception value S(S1) in the reference state, and the second reference reception value is the reception value S(S2) in the reference state. Also, in FIG. 5, the reference state can be set so that S(S1) - S(S2) is zero. When the deflection angle of the movable reflector 120 in the second direction Y becomes smaller than the deflection angle of the movable reflector 120 in the second direction Y in the reference state, S(S1) - S(S2) takes a positive value. In this case, the correction unit 150 can correct the detection result of the detection unit 122 so that S(S1) - S(S2) returns to zero, that is, so that the deflection angle of the movable reflector 120 in the second direction Y increases. Furthermore, when the deflection angle of the movable reflector 120 in the second direction Y becomes larger than the deflection angle of the movable reflector 120 in the second direction Y in the reference state, S(S1) - S(S2) takes a negative value. In this case, the correction unit 150 can correct the detection result of the detection unit 122 so that S(S1) - S(S2) returns to zero, that is, so that the deflection angle of the movable reflector 120 in the second direction Y becomes smaller. Therefore, by correcting the detection result by the correction unit 150, the drive signal of the movable reflector 120 is corrected, and the deflection angle of the movable reflector 120 in the second direction Y is maintained at the deflection angle in the reference state.

[0044] For example, the difference between the first reference reception value for the third spot S3 and the second reference reception value for the fourth spot S4 can be set to zero. For example, in FIGS. 6 and 7, the first reference reception value is the reception value S(S3) in the reference state, and the second reference reception value is the reception value S(S4) in the reference state. Also, in FIG. 7, the reference state can be set so that S(S3) - S(S4) is zero. When the deflection angle of the movable reflector 120 in the first direction X becomes smaller than the deflection angle of the movable reflector 120 in the first direction X in the reference state, S(S3) - S(S4) takes a positive value. In this case, the correction unit 150 can correct the detection result of the detection unit 122 so that S(S3) - S(S4) returns to zero, that is, so that the deflection angle of the movable reflector 120 in the first direction X increases. Furthermore, when the deflection angle of the movable reflector 120 in the first direction X becomes larger than the deflection angle of the movable reflector 120 in the first direction X in the reference state, S(S3) - S(S4) takes a negative value. In this case, the correction unit 150 can correct the detection result of the detection unit 122 so that S(S3) - S(S4) returns to zero, that is, so that the deflection angle of the movable reflector 120 in the first direction X becomes smaller. Therefore, by correcting the detection result by the correction unit 150, the drive signal of the movable reflector 120 is corrected, and the deflection angle of the movable reflector 120 in the second direction Y is maintained at the deflection angle in the reference state.

[0045] Fig. 8 is a diagram showing an example of the relationship between the structure 200, the scanning line L of the movable reflecting unit 120, and the spot irradiated onto the scanning line L in the sensor device 10 according to the modified example. Fig. 8 is a diagram showing the area where the scanning line L is formed, viewed from the movable reflecting unit 120 side.

[0046] 8, the ninth spot S9 and the tenth spot S10, which are aligned along the direction of resonant driving of the movable reflector 120, i.e., the first direction X, at approximately the center in the second direction Y of the region where the scanning line L is formed, are indicated by white circles. Also, the eleventh spot S11 and the twelfth spot S12, which are aligned along the direction of resonant driving of the movable reflector 120, i.e., the first direction X, are indicated by white circles at the upper part in the second direction Y of the region where the scanning line L is formed.

[0047] The structure 200 intersects with the scanning line L of the movable reflector 120. Specifically, the structure 200 is a member such as a wire that extends linearly along the second direction Y. The width of the structure 200 in the first direction X is narrower than the width of the spot generated by the movable reflector 120 in the first direction X. Therefore, it is possible to suppress electromagnetic waves attenuated by the structure 200.

[0048] 8, the first portion of the structure 200 may be, for example, a portion of the structure 200 that is irradiated by the ninth spot S9. The second portion of the structure 200 may be a portion of the structure 200 that is irradiated by the tenth spot S10. The intensities of the signals generated in the receiving unit 130 by the electromagnetic waves reflected by the structure 200, such as the first reference received value and the second reference received value, vary depending on the area of ​​the spot that is irradiated on the structure 200 and the intensity distribution of the spot.

[0049] Fig. 9 is a graph showing an example of changes in the reception value S(S9) generated in the receiving unit 130 by the ninth spot S9 and the reception value S(S10) generated in the receiving unit 130 by the tenth spot S10 when the deflection angle in the first direction X of the movable reflecting unit 120 fluctuates. Fig. 10 is a graph showing the difference between the two reception values ​​S(S9) and S(S10) shown in Fig. 9.

[0050] The horizontal axis of the graph in Fig. 9 represents the deflection angle of the movable reflecting unit 120 in the first direction X. The vertical axis of the graph in Fig. 9 represents the intensity of each of the two received values ​​S(S9) and S(S10). The solid line marked with "PX" represents the deflection angle of the movable reflecting unit 120 in the first direction X in the reference state. The larger the value on the horizontal axis, the greater the deflection of the movable reflecting unit 120 in the first direction X.

[0051] The horizontal axis of the graph in Fig. 10 represents the deflection angle of the movable reflector 120 in the second direction Y. The vertical axis of the graph in Fig. 10 represents the difference S(S10)-S(S9) between the two received values ​​S(S9) and S(S10). The solid line marked "PY" represents the deflection angle of the movable reflector 120 in the second direction Y in the reference state.

[0052] Fig. 11 is a diagram showing an example of the relationship between the structure 200, the ninth spot S9, and the tenth spot S10 in the reference state. Fig. 12 is a diagram showing an example of the relationship between the structure 200, the ninth spot S9, and the tenth spot S10 when the deflection angle of the movable reflecting unit 120 in the first direction X is smaller than the deflection angle in the reference state. Fig. 13 is a diagram showing an example of the relationship between the structure 200, the ninth spot S9, and the tenth spot S10 when the deflection angle of the movable reflecting unit 120 in the first direction X is larger than the deflection angle in the reference state. In Figs. 11 to 13, a double-headed arrow passing through the ninth spot S9 and the tenth spot S10 indicates the direction of vibration of the movable reflecting unit 120 in the first direction X.

[0053] 11, the area of ​​the ninth spot S9 that is irradiated onto the structure 200 is substantially equal to the area of ​​the tenth spot S10 that is irradiated onto the structure 200. Therefore, as shown in FIG. 10, S(S10)-S(S9) in the reference state is zero.

[0054] 12, the area of ​​the tenth spot S10 that is irradiated onto the structure 200 is larger than the area of ​​the ninth spot S9 that is irradiated onto the structure 200. Therefore, S(S10)-S(S9) shown in FIG. 10 becomes a positive value, and it can be detected that the deflection angle of the movable reflecting part 120 in the first direction X has become smaller than the deflection angle in the reference state.

[0055] 13, the area of ​​the tenth spot S10 that is irradiated onto the structure 200 is smaller than the area of ​​the ninth spot S9 that is irradiated onto the structure 200. Therefore, S(S10)-S(S9) shown in Fig. 10 becomes a negative value, and it can be detected that the deflection angle of the movable reflecting part 120 in the first direction X has become larger than the deflection angle in the reference state.

[0056] For example, the difference between the first reference reception value for the ninth spot S9 and the second reference reception value for the tenth spot S10 can be set to zero. For example, in FIGS. 9 and 10, the first reference reception value is the reception value S(S9) in the reference state, and the second reference reception value is the reception value S(S10) in the reference state. Also, in FIG. 10, the reference state can be set so that S(S10) - S(S9) is zero. If the deflection angle of the movable reflector 120 in the second direction Y varies from the deflection angle of the movable reflector 120 in the second direction Y in the reference state, and S(S10) - S(S9) is a positive or negative value, the correction unit 150 can correct the detection result of the detection unit 122 so that S(S10) - S(S9) returns to zero.

[0057] 9 to 13 illustrate an example in which the ninth spot S9 and the tenth spot S10 are used. However, even when the eleventh spot S11 and the twelfth spot S12 are used, the same can be achieved as in the example explained using FIGS.

[0058] Figure 14 is a graph showing an example of the relationship between the deflection angle of the movable reflecting unit 120 in the second direction Y and the difference S(S11)-S(S12) between the received value S(S11) of the signal generated in the receiving unit 130 by the 11th spot S11 and the received value S(S12) of the signal generated in the receiving unit 130 by the 12th spot S12.

[0059] 14, the horizontal axis of the graph represents the deflection angle of the movable reflecting unit 120 in the second direction Y. The vertical axis of the graph represents the difference S(S11)-S(S12) between the received value S(S11) of the signal generated in the receiving unit 130 by the eleventh spot S11 and the received value S(S12) of the signal generated in the receiving unit 130 by the twelfth spot S12.

[0060] Fig. 15 is a diagram showing an example of the relationship between the structure 200, the ninth spot S9, the tenth spot S10, the eleventh spot S11, and the twelfth spot S12 in the reference state. Fig. 16 is a diagram showing an example of the relationship between the structure 200, the ninth spot S9, the tenth spot S10, the eleventh spot S11, and the twelfth spot S12 in a case where the deflection angle of the movable reflecting unit 120 in the second direction Y is smaller than the deflection angle in the reference state. Fig. 17 is a diagram showing an example of the relationship between the structure 200, the ninth spot S9, the tenth spot S10, the eleventh spot S11, and the twelfth spot S12 in a case where the deflection angle of the movable reflecting unit 120 in the first direction X is larger than the deflection angle in the reference state. 15 to 17, the double-headed arrow passing through the ninth spot S9 and the tenth spot S10 and the double-headed arrow passing through the eleventh spot S11 and the twelfth spot S12 indicate the direction of vibration of the movable reflecting unit 120 in the first direction X.

[0061] 15 to 17, the area of ​​the ninth spot S9 that is irradiated onto the structure 200 and the area of ​​the tenth spot S10 that is irradiated onto the structure 200 are substantially equal to each other.

[0062] 16, the difference between the area of ​​the eleventh spot S11 that is irradiated onto the structure 200 and the area of ​​the twelfth spot S12 that is irradiated onto the structure 200 is smaller than the difference between the area of ​​the eleventh spot S11 that is irradiated onto the structure 200 and the area of ​​the twelfth spot S12 that is irradiated onto the structure 200 in FIG. 15. Therefore, as shown in FIG. 14, the difference S(S11)-S(S12) when the deflection angle of the movable reflecting unit 120 in the second direction Y becomes smaller than the deflection angle in the reference state is smaller than the difference S(S11)-S(S12) in the reference state. In this case, the correction unit 150 can correct the detection result of the detection unit 122 so that the difference S(S11)-S(S12) returns to the difference S(S11)-S(S12) in the reference state.

[0063] 17, the difference between the area of ​​the eleventh spot S11 that is irradiated onto the structure 200 and the area of ​​the twelfth spot S12 that is irradiated onto the structure 200 is larger than the difference between the area of ​​the eleventh spot S11 that is irradiated onto the structure 200 and the area of ​​the twelfth spot S12 that is irradiated onto the structure 200 in FIG. 15. Therefore, as shown in FIG. 14, the difference S(S11)-S(S12) when the deflection angle of the movable reflecting unit 120 in the second direction Y becomes larger than the deflection angle in the reference state is larger than the difference S(S11)-S(S12) in the reference state. In this case, the correction unit 150 can correct the detection result of the detection unit 122 so that the difference S(S11)-S(S12) returns to the difference S(S11)-S(S12) in the reference state.

[0064] Although the embodiments and modifications have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0065] For example, in the embodiment, the sensor device 10 is a coaxial LiDAR. However, the sensor device 10 may be a biaxial LiDAR.

[0066] This application claims priority based on Japanese Patent Application No. 2020-062799, filed on March 31, 2020, the disclosure of which is incorporated herein in its entirety. Below, examples of reference forms are added. 1. A movable reflecting unit that reflects electromagnetic waves toward a predetermined scanning range; a detection unit that detects a deflection angle of the movable reflecting unit; a receiving unit that receives the electromagnetic waves reflected or scattered by structures located within the scanning range; a correction unit that corrects a detection result of the detection unit based on a reception result of the electromagnetic wave reflected by the structure by the reception unit; A sensor device comprising: 2. In the sensor device described in 1., The correction unit corrects the detection result of the detection unit based on the relationship between a first reception value by the receiving unit of the electromagnetic wave reflected or scattered by a first part of the structure and a second reception value by the receiving unit of the electromagnetic wave reflected or scattered by a second part of the structure. 3. In the sensor device described in 2., The correction unit corrects the detection result of the detection unit based on a comparison result between the relationship between the first received value and the second received value and the relationship between a first reference received value by the receiving unit of the electromagnetic wave reflected or scattered by the first part of the structure when the detection unit operates in a reference state and a second reference received value by the receiving unit of the electromagnetic wave reflected or scattered by the second part of the structure when the detection unit operates in the reference state. 4. In the sensor device described in 3., The sensor device further includes a first adjustment unit that adjusts the position of the structure so that the relationship between the first reference reception value and the second reference reception value becomes a predetermined reference relationship. 5. In the sensor device according to 3. or 4., the movable reflecting portion reflects the electromagnetic wave emitted from the emitting portion toward the scanning range, The sensor device further includes a second adjustment unit that adjusts the emission timing of the electromagnetic wave from the emission unit so that the relationship between the first reference reception value and the second reference reception value becomes a predetermined reference relationship. 6. In the sensor device according to any one of 2. to 5., The sensor device, wherein the first portion and the second portion of the structure are offset in a direction of linear drive of the movable reflecting portion. 7. In the sensor device according to any one of 2. to 5., The sensor device, wherein the first portion and the second portion of the structure are offset in a direction of resonant driving of the movable reflecting portion. 8. In the sensor device according to any one of 1. to 7., The structure is located outside an area where a scan line of the movable reflecting portion is formed. 9. In the sensor device according to any one of 1. to 7., The structure intersects a scan line of the movable reflector. [Explanation of symbols]

[0067] 10 Sensor device 110 Exit section 120 Movable reflector 122 Detector 130 Receiving unit 140 Beam Splitter 150 Correction unit 162 1st adjustment section 164 2nd adjustment section 200 structures L scan line S1 1st spot S2 2nd spot S3 3rd spot S4 4th spot S5 5th Spot S6 6th spot S7 7th spot S8 8th spot S9 9th spot S10 10th spot S11 11th spot S12 12th spot X 1st direction Y Second direction

Claims

1. an emission unit that emits electromagnetic waves; a movable reflecting unit that reflects electromagnetic waves toward a predetermined scanning range; a detection unit that detects a deflection angle of the movable reflecting unit; a receiving unit that receives the electromagnetic waves reflected or scattered by a structure at least a portion of which is located within the scanning range; a correction unit that corrects the detection result of the detection unit based on a comparison result between a difference or ratio between a first reception value by the receiving unit of the electromagnetic wave reflected or scattered by a first portion of the structure and a second reception value by the receiving unit of the electromagnetic wave reflected or scattered by a second portion of the structure, and a relationship between a first reference reception value by the receiving unit of the electromagnetic wave reflected or scattered by the first portion of the structure when the detection unit operates in a reference state and a second reference reception value by the receiving unit of the electromagnetic wave reflected or scattered by the second portion of the structure when the detection unit operates in the reference state; a first adjustment unit that adjusts the position of the structure so that the relationship between the first reference reception value and the second reference reception value becomes a predetermined reference relationship; The structure; A sensor device comprising:

2. An emission unit that emits electromagnetic waves; a movable reflecting unit that reflects electromagnetic waves toward a predetermined scanning range; a detection unit that detects a deflection angle of the movable reflecting unit; a receiving unit that receives the electromagnetic waves reflected or scattered by a structure at least a portion of which is located within the scanning range; a correction unit that corrects the detection result of the detection unit based on a comparison result between a difference or ratio between a first reception value by the receiving unit of the electromagnetic wave reflected or scattered by a first portion of the structure and a second reception value by the receiving unit of the electromagnetic wave reflected or scattered by a second portion of the structure, and a relationship between a first reference reception value by the receiving unit of the electromagnetic wave reflected or scattered by the first portion of the structure when the detection unit operates in a reference state and a second reference reception value by the receiving unit of the electromagnetic wave reflected or scattered by the second portion of the structure when the detection unit operates in the reference state; The structure; Equipped with the movable reflecting portion reflects the electromagnetic wave emitted from the emitting portion toward the scanning range, The sensor device further includes a second adjustment unit that adjusts the emission timing of the electromagnetic wave from the emission unit so that the relationship between the first reference reception value and the second reference reception value becomes a predetermined reference relationship.

3. 3. The sensor device according to claim 1, the structure is one continuous structure having the first portion and the second portion; The sensor device, wherein the first portion and the second portion of the structure are offset in a direction of linear actuation of the movable reflecting portion.

4. 3. The sensor device according to claim 1, the structure is one continuous structure having the first portion and the second portion; The sensor device, wherein the first and second portions of the structure are offset in a direction of resonant driving of the movable reflector.

5. The sensor device according to any one of claims 1 to 4, The structure intersects a scan line of the movable reflector.

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