Sensor device

Abstract

A part of the electromagnetic wave emitted by the emission section (110) and reflected by the movable reflection section (120) is reflected or scattered by an object such as an object existing outside the sensor device (10). Another part of the electromagnetic wave emitted by the emission section (110) and reflected by the movable reflection section (120) is reflected or scattered by the structure (200) at a position closer to the movable reflection section (120) than the above object. The detection section (122) detects the oscillation angles in the first direction (X) and the second direction (Y) of the movable reflection section (120). The correction section (150) corrects the detection result of the detection section (122) based on the reception result of the electromagnetic wave reflected or scattered by the structure (200) received by the reception section (130).

Description

Technical Field

[0001] This invention relates to sensor devices. Background Technology

[0002] In recent years, various sensor devices, such as LiDAR (Light Detection and Ranging), have been developed. These sensor devices possess movable reflective parts, such as MEMS (Micro Electro Mechanical Systems) mirrors. By reflecting electromagnetic waves, such as infrared light, into a defined scanning range through these movable reflective parts, the sensor device can scan objects and other objects existing outside the sensor device.

[0003] Patent Document 1 describes a method of arranging a reflective member at one end of the scanning range of a movable reflective portion to determine the direction of the laser output reflected by the movable reflective portion. The laser reflected by the reflective member is received by a light-receiving portion. The distance from the movable reflective portion to the reflective member is calculated based on the light-receiving result of the light-receiving portion. Based on the distance from the movable reflective portion to the reflective member, the direction of the laser output reflected by the movable reflective portion is calculated.

[0004] Patent document 2 describes the following: A reflective member is provided on the housing that houses the movable reflective part and other components constituting the sensor device, and the offset of the scanning position of the movable reflective part is detected by using the laser reflected by the reflective member.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2016-6403

[0008] Patent Document 2: Japanese Patent Application Publication No. 2020-16481 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] Sensor devices sometimes include a detection unit for detecting the oscillation angle of a movable reflector. However, the sensitivity of this detection unit can sometimes be temperature-dependent. In such cases, the detection results may deviate from the designed results.

[0011] As an example of the problem to be solved by the present invention, one can cite the correction of the deviation between the detection result of the detection unit and the detection result of the design state for the oscillation angle of the movable reflector.

[0012] Methods for solving problems

[0013] The invention described in technical solution 1 is a sensor device, which comprises:

[0014] The movable reflector reflects electromagnetic waves within a specified scanning range;

[0015] The detection unit detects the oscillation angle of the aforementioned movable reflective part;

[0016] The receiving unit receives the electromagnetic waves reflected or scattered by the structure located within the aforementioned scanning range;

[0017] The correction unit corrects the detection results of the detection unit based on the reception results of the aforementioned receiving unit receiving the aforementioned electromagnetic waves reflected by the aforementioned structure. Attached Figure Description

[0018] [ Figure 1 [A diagram illustrating the sensor device involved in the embodiment.]

[0019] [ Figure 2 This is a diagram illustrating an example of the relationship between the structure, the scan line of the movable reflector, and the point illuminated on the scan line.

[0020] [ Figure 3 To show the result of Figure 2 The diagram shows an example of the signal generated at the receiving unit at the first and second points.

[0021] [ Figure 4 This is a graph illustrating an example of the change in the received value of the signal generated at the first point and the received value of the signal generated at the second point when the oscillation angle of the movable reflector changes in the second direction.

[0022] [ Figure 5 To show Figure 4 The graph shows the difference between the two received values.

[0023] [ Figure 6 A graph illustrating an example of the change in the received value of the signal generated at the third point and the received value of the signal generated at the fourth point when the oscillation angle of the movable reflector changes in the first direction.

[0024] [ Figure 7 To show Figure 6 The graph shows the difference between the two received values.

[0025] [ Figure 8 This is a diagram illustrating an example of the relationship between the structure, the scan line of the movable reflective part, and the point irradiated onto the scan line in the sensor device involved in the modified example.

[0026] [ Figure 9A graph illustrating an example of the change in the received value of the signal generated at the ninth point and the received value of the signal generated at the tenth point when the oscillation angle of the movable reflector changes in the first direction.

[0027] [ Figure 10 To show Figure 9 The graph shows the difference between the two received values.

[0028] [ Figure 11 This is a diagram illustrating an example of the relationship between the construct, the ninth point, and the tenth point in the baseline state.

[0029] [ Figure 12 This diagram illustrates an example of the relationship between the structure, the ninth point, and the tenth point when the oscillation angle of the movable reflector in the first direction is less than the oscillation angle in the reference state.

[0030] [ Figure 13 This diagram illustrates an example of the relationship between the structure, the ninth point, and the tenth point when the oscillation angle of the movable reflector in the first direction is greater than the oscillation angle in the reference state.

[0031] [ Figure 14 This is a graph illustrating an example of the relationship between the oscillation angle of the movable reflector in the second direction and the difference between the received value of the signal generated at the eleventh point and the received value of the signal generated at the twelfth point.

[0032] [ Figure 15 This is a diagram illustrating an example of the relationship between the construct, the ninth point, the tenth point, the eleventh point, and the twelfth point in the baseline state.

[0033] [ Figure 16 This diagram illustrates an example of the relationship between the structure, the ninth point, the tenth point, the eleventh point, and the twelfth point when the oscillation angle of the movable reflector in the second direction is less than the oscillation angle in the reference state.

[0034] [ Figure 17 This diagram illustrates an example of the relationship between the structure, the ninth point, the tenth point, the eleventh point, and the twelfth point when the oscillation angle of the movable reflector in the first direction is greater than the oscillation angle in the reference state. Detailed Implementation

[0035] The embodiments of the present invention will be described below using the accompanying drawings. It should be noted that in all the drawings, the same components are labeled with the same reference numerals, and descriptions are omitted where appropriate.

[0036] Figure 1 A diagram illustrating the sensor device 10 according to the embodiment.

[0037] Figure 1 In the middle, the first direction X and the second direction Y intersect each other, specifically orthogonal. Figure 1 In this diagram, the first direction X is horizontal. The direction of the arrow indicating the first direction X, i.e., the positive direction of the first direction X, is the left direction when observing from the movable reflector 120 towards its scanning range (described later). The opposite direction of the arrow indicating the first direction X, i.e., the negative direction of the first direction X, is the right direction when observing from the side where the movable reflector 120 is located towards its scanning range. The second direction Y is vertical. The direction of the arrow indicating the second direction Y, i.e., the positive direction of the second direction Y, is upward. The opposite direction of the arrow indicating the second direction Y, i.e., the negative direction of the second direction Y, is downward.

[0038] As can be clearly seen from the description in this manual, the first direction X can be a direction different from the horizontal direction, and the second direction Y can be a direction different from the vertical direction.

[0039] The sensor device 10 includes: an emission part 110, a movable reflective part 120, a detection part 122, a receiving part 130, a beam splitter 140, a correction part 150, a first adjustment part 162, and a second adjustment part 164. Figure 1 The dashed lines extending to the emission section 110, movable reflector 120, receiver 130, beam splitter 140, and scan line L represent electromagnetic waves propagating within the range of the emission section 110, movable reflector 120, receiver 130, beam splitter 140, and scan line L. Figure 1 In the process, electromagnetic waves reflected from the movable reflector 120 toward the scan line L irradiate approximately the center of the area formed by the scan line L.

[0040] The emission section 110 emits pulsed infrared electromagnetic waves at regular intervals. The emission section 110 is, for example, a laser diode (LD) or other device capable of converting electrical current into electromagnetic waves such as light. The electromagnetic waves emitted from the emission section 110 are reflected by the beam splitter 140 and incident on the movable reflector 120.

[0041] The movable reflector 120 reflects the electromagnetic waves emitted by the emission section 110 within a predetermined scanning range. The scanning range of the movable reflector 120 is the range that can be illuminated by the electromagnetic waves reflected by the movable reflector 120. The movable reflector 120 is, for example, a biaxial MEMS mirror. The movable reflector 120 is driven in a sinusoidal shape along a first direction X, and in a sawtooth shape along a second direction Y at a frequency lower than the sinusoidal wave along the first direction X. That is, 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.

[0042] The detection unit 122 detects the oscillation angles of the movable reflector 120 in the first direction X and the second direction Y. The detection unit 122 is, for example, a piezoresistive element provided on the movable reflector 120. The oscillation 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, when the sensitivity of the detection unit 122 is temperature-dependent, the oscillation angle of the movable reflector 120 based on the detection results of the detection unit 122 will change with temperature, resulting in the oscillation angle of the movable reflector 120 sometimes changing with temperature. As described below, in this embodiment, the correction unit 150 can correct the oscillation angle of the movable reflector 120 based on the detection results of the detection unit 122.

[0043] A portion of the electromagnetic waves emitted from the emission section 110 and reflected by the movable reflector 120 are reflected or scattered by objects or other objects located outside the sensor device 10. These electromagnetic waves return to the movable reflector 120 and pass sequentially through the movable reflector 120 and the transmission beam splitter 140 before reaching the receiving section 130 and being received by it. The receiving section 130 is, for example, an avalanche photodiode (APD) or other element capable of converting electromagnetic waves such as light into electrical signals such as current.

[0044] Another portion of the electromagnetic waves emitted from the emission section 110 and reflected by the movable reflector 120 are reflected or scattered by the structure 200, which is located closer to the movable reflector 120 than the object. This electromagnetic wave returns towards the movable reflector 120 and passes sequentially through the movable reflector 120 and the transmission beam splitter 140 before being received by the receiving section 130. The structure 200 can be, for example, a metal with a surface treatment that ensures high stability over time, such as electroplating.

[0045] The distance from the movable reflector 120 to the structure 200 is shorter than the distance from the movable reflector 120 to the object. Therefore, the time from the emission of electromagnetic waves from the emission unit 110, through reflection of electromagnetic waves based on the object, to the reception of electromagnetic waves based on the receiving unit 130 is shorter than the time from the emission of electromagnetic waves from the emission unit 110, through reflection of electromagnetic waves based on the structure 200, to the reception of electromagnetic waves based on the receiving unit 130. Therefore, the sensor device 10 can distinguish whether the signal generated in the receiving unit 130 originates from the structure 200 or from the object based on the time difference of the signal generated in the receiving unit 130.

[0046] The sensor device 10 may include a structure 200. Alternatively, the structure 200 may be disposed on the exterior of the sensor device 10. When the sensor device 10 includes a structure 200, the structure 200 may be disposed, for example, in a window portion of the housing that houses the components constituting the sensor device 10, such as the emission portion 110, the movable reflector 120, the receiver 130, and the beam splitter 140, i.e., a portion through which electromagnetic waves can pass between the interior and exterior of the housing. However, the location where the structure 200 may be disposed is not limited to a window portion.

[0047] In this embodiment, the calibration unit 150, the first adjustment unit 162, and the second adjustment unit 164 are shown as functional modules, not as hardware units. The calibration unit 150, the first adjustment unit 162, and the second adjustment unit 164 can be implemented using any combination of hardware and software, centered on any computer's CPU, memory, program loaded in memory, storage medium such as a hard disk storing the program, or network connection interface. Furthermore, there are various variations in their implementation methods and apparatus.

[0048] The correction unit 150 corrects the detection results of the detection unit 122 based on the reception results of the electromagnetic waves reflected or scattered by the structure 200 received by the receiving unit 130. Through the correction of the correction unit 150, the deviation of the oscillation angle of the movable reflector 120 based on the detection results of the detection unit 122 and the detection results of the design state can be corrected.

[0049] Figure 2 This diagram illustrates an example of the relationship between the structure 200, the scan line L of the movable reflective part 120, and the point illuminated on the scan line L.

[0050] Figure 2 In the process, the scan line L is folded back in the first direction X (i.e., the direction of resonance drive of the movable reflector 120) and extends in the second direction Y (i.e., from the positive direction of the linear drive direction of the movable reflector 120 to the negative direction).

[0051] Figure 2 The diagram shows eight points located on the scan line L, namely point S1, point S2, point S3, point S4, point S5, point S6, point S7, and point S8. Each point is generated by electromagnetic waves emitted from the emission part 110 and reflected by the movable reflector 120 to the structure 200.

[0052] Points S1, S2, S3, and S4 are each used for correction by the correction unit 150. At least a portion of each of the points S1, S2, S3, and S4 is illuminated by the structure 200. It should be noted that points S1, S2, S3, and S4 can be used for sensing by the sensor device 10. Points S1 and S2 are offset in the direction of linear drive of the movable reflector 120, i.e., the second direction Y. Furthermore, point S2 is located outside the area formed by the scan line L in the second direction Y compared to point S1. Points S3 and S4 are offset in the direction of resonant drive of the movable reflector 120, i.e., the first direction X. Furthermore, point S4 is located outside the area formed by the scan line L in the first direction X compared to point S3.

[0053] Points S5, S6, S7, and S8 are each a portion of the points used for sensing by the sensor device 10. Any portion of each of these points may not be illuminated by the structure 200. Therefore, with respect to points S5, S6, S7, and S8, the energy of the electromagnetic waves illuminating the object is not reduced by the structure 200, enabling efficient sensing of the object. Points S5 and S6 are offset to the left relative to points S1 and S2, respectively. Points S7 and S8 are offset upwards relative to points S3 and S4, respectively.

[0054] The structure 200 is located outside the area formed by the scan line L of the movable reflector 120. If the movable reflector 120 is located inside the area formed by the scan line L, the sensor device 10 may be unable to detect objects in the area where the structure 200 is positioned, or its detection performance may deteriorate. In contrast, Figure 2 In the example shown, the area where the sensor device 10 cannot detect an object or where the detection performance deteriorates is limited to the area outside the area formed by the scan line L of the movable reflective part 120.

[0055] The correction unit 150 can correct the detection result of the detection unit 122 based on the relationship between a first received value received by the receiving unit 130 from electromagnetic waves reflected or scattered by a predetermined first portion of the structure 200 and a second received value received by the receiving unit 130 from electromagnetic waves 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 based on the relationship between the first and second received values ​​(e.g., at least one of the difference or ratio between the first and second received values) and the deviation of the detection result of the detection unit 122 from the detection result of a reference state such as a design state or an initial state.

[0056] The correction unit 150 can correct the detection result of the detection unit 122 based on the relationship between the first received value and the second received value, and a comparison result between the first reference received value received by the receiving unit 130 from the electromagnetic waves reflected or scattered by the first part of the structure 200 when the detection unit 122 operates in the reference state, and the second reference received value received by the receiving unit 130 from the electromagnetic waves reflected or scattered by the second part of the structure 200 when the detection unit 122 operates in the reference state. The relationship between the first reference received value and the second reference received value can be set as a known, predetermined reference relationship. For example, at least one of the difference and ratio of the first reference received value and the second reference received value can be set as a known, predetermined reference value. In this case, if the sensitivity of the detection unit 122 changes compared to the sensitivity of the detection unit 122 when it is in the reference state due to fixed factors such as temperature, and the oscillation angle of the movable reflector 120 changes compared to the oscillation angle of the detection unit 122 when it is in the reference state, then the relationship between the first received value and the second received value also changes compared to the predetermined reference relationship. The correction unit 150 can correct the detection result of the detection unit 122 in a manner that restores the relationship between the first received value and the second received value to the reference relationship specified above. The first reference received value and the second reference received value may, for example, be substantially equal to each other.

[0057] In one example, the first part of the structure 200 is defined as the area illuminated by the first point S1 in the structure 200 and its surrounding area, and the second part of the structure 200 is defined as the area illuminated by the second point S2 in the structure 200 and its surrounding area. That is, the first part and the second part of the structure 200 can be offset in the direction of linear drive of the movable reflector 120, that is, in the second direction Y.

[0058] The first adjustment unit 162 can adjust the position of the structure 200 in such a way that the relationship between the first reference receiving value and the second reference receiving value becomes a predetermined reference relationship. For example, the first adjustment unit 162 can move the structure 200 along the second direction Y. As a result, the relationship between the first reference receiving value of the first point S1 and the second reference receiving value of the second point S2 can become a predetermined reference relationship.

[0059] In another example, the first part of the structure 200 is defined as the area illuminated by the third point S3 in the structure 200 and its surrounding area, and the second part of the structure 200 is defined as the area illuminated by the fourth point S4 in the structure 200 and its surrounding area. That is, the first part and the second part of the structure 200 can be offset in the direction of the resonant drive of the movable reflector 120, that is, in the first direction X.

[0060] The second adjustment unit 164 can adjust the timing of the electromagnetic wave emission from the emission unit 110 in such a way that the relationship between the first reference received value and the second reference received value is a predetermined reference relationship. Therefore, the relationship between the first reference received value at the third point S3 and the second reference received value at the fourth point S4 can be made into a predetermined reference relationship.

[0061] 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 waves from the emission unit 110 by the second adjustment unit 164 can be appropriately combined. For example, by moving the structure 200 in the second direction Y by the first adjustment unit 162, the oscillation angle of the movable reflector 120 in the second direction Y based on the detection result of the detection unit 122 is corrected. By adjusting the emission unit 110 by the second adjustment unit 164, the oscillation angle of the movable reflector 120 in the first direction X based on the detection result of the detection unit 122 is corrected. In this case, the structure 200 can be fixed in a way that prevents it from moving along the first direction X. Alternatively, the structure 200 can be moved in both the first direction X and the second direction Y by the first adjustment unit 162, thereby correcting the oscillation angles of the movable reflector 120 in the first direction X and the second direction Y based on the detection result of the detection unit 122. In this case, the second adjustment unit 164 does not need to adjust the emission unit 110.

[0062] Figure 3 To show by Figure 2 The diagram shows an example of the signal generated by the first point S1 and the second point S2 in the receiving unit 130. Figure 4 A graph illustrating an example of the change in the received value S(S1) of the signal generated by the first point S1 at the receiving unit 130 and the received value S(S2) of the signal generated by the second point S2 at the receiving unit 130 when the oscillation angle of the second direction Y of the movable reflector 120 changes. Figure 5 To show Figure 4 The graph shown is a graph of the difference between the two received values ​​S(S1) and S(S2), namely S(S1)-S(S2). Figure 6 A graph illustrating an example of the change in the received value S(S3) of the signal generated at the receiving unit 130 by the third point S3 and the received value S(S4) of the signal generated at the receiving unit 130 by the fourth point S4 when the oscillation angle of the first direction X of the movable reflector 120 changes. Figure 7 To show Figure 6 The graph shown is a graph of the difference between the two received values ​​S(S3) and S(S4), namely S(S3)-S(S4).

[0063] Figure 3In the diagram, the signal with peak value 'a' represents the signal generated by the first point S1. Conversely, the signal with peak value 'b' represents the signal generated by the second point S2. Figures 4-6 The received values ​​S(S1), S(S2), S(S3), S(S4), etc., are the received values ​​of the signals generated at each point in the receiving unit 130. Figure 3 The peak values ​​a, b, etc. are the peak values ​​of the signals generated at each point in the receiving unit 130.

[0064] Figure 4 The horizontal axis of the graph represents the oscillation angle of the movable reflector 120 in the second direction Y. Additionally, Figure 4 The vertical axis of the graph represents the intensity of the two received values ​​S(S1) and S(S2). The solid line marked "PY" represents the oscillation angle of the movable reflector 120 in the second direction Y under the reference state. For example, Figure 2 In the example shown, if the movable reflector 120 oscillates significantly in the second direction Y, the first point S1 and the second point S2 move outward. The area of ​​the first point S1 that is illuminated by the structure 200 decreases, and the received value S(S1) decreases. Conversely, the area of ​​the second point S2 that is illuminated by the structure 200 increases, and the received value S(S2) increases. Therefore, as the oscillation angle of the movable reflector 120 in the second direction Y changes, such as... Figure 4 The received values ​​S(S1) and S(S2) change as shown in the chart.

[0065] Figure 5 The horizontal axis of the graph represents the oscillation angle of the movable reflector 120 in the second direction Y. Additionally, Figure 5 The vertical axis of the graph represents the difference between the two received values ​​S(S1) and S(S2). The solid line marked "PY" represents the oscillation angle of the movable reflector 120 in the second direction Y under the reference state.

[0066] Figure 6 The horizontal axis of the graph represents the oscillation angle of the movable reflector 120 in the first direction X. Additionally, Figure 6 The vertical axis of the graph represents the intensity of the two received values ​​S(S3) and S(S4). The solid line marked "PY" represents the oscillation angle of the movable reflector 120 in the first direction X under the reference state. The larger the value on the horizontal axis, the more significantly the movable reflector 120 oscillates in the first direction X. For example, Figure 2 In the example shown, if the movable reflector 120 oscillates significantly in the first direction X, then the third point S3 and the fourth point S4 move outward. The area of ​​the third point S3 that is illuminated by the structure 200 decreases, and the received value S(S3) decreases. Conversely, the area of ​​the fourth point S4 that is illuminated by the structure 200 increases, and the received value S(S4) increases. Therefore, as the oscillation angle of the movable reflector 120 in the first direction X changes, such as... Figure 6The received values ​​S(S3) and S(S4) change as shown in the chart.

[0067] Figure 7 The horizontal axis of the graph represents the oscillation angle of the movable reflector 120 in the first direction X. Additionally, Figure 7 The vertical axis of the graph represents the difference between the two received values ​​S(S3) and S(S4). The solid line marked "PY" represents the oscillation angle of the movable reflector 120 in the first direction X under the reference state.

[0068] For example, the difference between the first reference received value at point S1 and the second reference received value at point S2 can be set to zero. Figure 4 and Figure 5 In this context, the first reference received value refers to the received value S(S1) under reference conditions, and the second reference received value refers to the received value S(S2) under reference conditions. Additionally, Figure 5 In this configuration, the reference state can be set such that S(S1)-S(S2) becomes zero. When the oscillation angle of the movable reflector 120 in the second direction Y is less than the oscillation angle of the movable reflector 120 in the second direction Y in the reference state, S(S1)-S(S2) becomes a positive value. In this case, the correction unit 150 can correct the detection result of the detection unit 122 by restoring S(S1)-S(S2) to zero, that is, by increasing the oscillation angle of the movable reflector 120 in the second direction Y. Conversely, when the oscillation angle of the movable reflector 120 in the second direction Y is greater than the oscillation angle of the movable reflector 120 in the reference state, S(S1)-S(S2) becomes a negative value. In this case, the correction unit 150 can correct the detection result of the detection unit 122 by restoring S(S1)-S(S2) to zero, that is, by increasing the oscillation angle of the movable reflector 120 in the second direction Y. Therefore, by using the correction unit 150 to correct the detection result, the drive signal of the movable reflector 120 is corrected, and the oscillation angle of the second direction Y of the movable reflector 120 is maintained at the oscillation angle of the reference state.

[0069] For example, the difference between the first reference received value at point S3 and the second reference received value at point S4 can be set to zero. Figure 6 and Figure 7 In this context, the first reference received value refers to the received value S(S3) under the reference state, and the second reference received value refers to the received value S(S4) under the reference state. Additionally, Figure 7In this configuration, the reference state can be set such that S(S3)-S(S4) becomes zero. When the oscillation angle of the movable reflector 120 in the first direction X is less than the oscillation angle of the movable reflector 120 in the first direction X in the reference state, S(S3)-S(S4) becomes a positive value. In this case, the correction unit 150 can correct the detection result of the detection unit 122 by restoring S(S3)-S(S4) to zero, that is, by increasing the oscillation angle of the movable reflector 120 in the first direction X. Conversely, when the oscillation angle of the movable reflector 120 in the first direction X is greater than the oscillation angle of the movable reflector 120 in the reference state, S(S3)-S(S4) becomes a negative value. In this case, the correction unit 150 can correct the detection result of the detection unit 122 by restoring S(S3)-S(S4) to zero, that is, by decreasing the oscillation angle of the movable reflector 120 in the first direction X. Therefore, by using the correction unit 150 to correct the detection result, the drive signal of the movable reflector 120 is corrected, and the oscillation angle of the second direction Y of the movable reflector 120 is maintained at the oscillation angle of the reference state.

[0070] Figure 8 This is a diagram illustrating an example of the relationship between the structure 200, the scan line L of the movable reflective part 120, and the point irradiated on the scan line L in the sensor device 10 involved in the modified example. Figure 8 This is a diagram showing the area formed by the scan line L when viewed from the side of the movable reflective part 120.

[0071] Figure 8 In the diagram, white circles indicate the ninth point S9 and the tenth point S10, located approximately at the center of the second direction Y within the region formed by the scan line L, along the direction of resonance drive of the movable reflector 120, i.e., the first direction X. Additionally, white circles indicate the eleventh point S11 and the twelfth point S12, located at the upper part of the second direction Y within the region formed by the scan line L, along the direction of resonance drive of the movable reflector 120, i.e., the first direction X.

[0072] The structure 200 intersects the scan line L of the movable reflector 120. Specifically, the structure 200 is a wire or similar component extending linearly along the second direction Y. The width of the structure 200 in the first direction X is narrower than the width of the point generated by the movable reflector 120 in the first direction X. Therefore, electromagnetic waves weakened by the structure 200 can be suppressed.

[0073] Figure 8In the example shown, the first part of the structure 200 can be, for example, the part of the structure 200 illuminated by the ninth point S9. Furthermore, the second part of the structure 200 can be the part of the structure 200 illuminated by the tenth point S10. The intensity of the signals generated at 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, varies according to the area of ​​the point illuminating the structure 200 and the intensity distribution of the point.

[0074] Figure 9 A graph illustrating an example of the change in the received value S(S9) generated at the receiving unit 130 by the ninth point S9 and the received value S(S10) generated at the receiving unit 130 by the tenth point S10 when the oscillation angle of the first direction X of the movable reflector 120 changes. Figure 10 To show Figure 9 The graph shows the difference between the two received values ​​S(S9) and S(S10).

[0075] Figure 9 The horizontal axis of the graph represents the oscillation angle of the movable reflector 120 in the first direction X. Additionally, Figure 9 The vertical axis of the graph represents the intensity of the two received values ​​S(S9) and S(S10). The solid line marked "PY" represents the oscillation angle of the movable reflector 120 in the first direction X under the reference state. The larger the value of the horizontal axis, the more significantly the movable reflector 120 oscillates in the first direction X.

[0076] Figure 10 The horizontal axis of the graph represents the oscillation angle of the movable reflector 120 in the second direction Y. Additionally, Figure 10 The vertical axis of the graph represents the difference between the two received values ​​S(S9) and S(S10), i.e., S(S10)-S(S9). The solid line marked "PY" represents the oscillation angle of the movable reflector 120 in the second direction Y under the reference state.

[0077] Figure 11 A diagram illustrating an example of the relationship between structure 200, point S9, and point S10 in the baseline state. Figure 12 This diagram illustrates an example of the relationship between structure 200, ninth point S9, and tenth point S10 when the oscillation angle of the movable reflector 120 in the first direction X is less than the oscillation angle in the reference state. Figure 13 This diagram illustrates an example of the relationship between structure 200, ninth point S9, and tenth point S10 when the oscillation angle of the movable reflector 120 in the first direction X is greater than the oscillation angle in the reference state. Figures 11-13 In the diagram, the direction of vibration of the movable reflector 120 in the first direction X is indicated by the double-headed arrows at points S9 and S10.

[0078] Figure 11 In point S9, the area of ​​structure 200 illuminated by sunlight is substantially equal to the area of ​​structure 200 illuminated by sunlight in point S10. Therefore, as Figure 10 As shown, S(S10)-S(S9) becomes zero in the reference state.

[0079] Figure 12 In point S10, the area of ​​structure 200 illuminated is greater than the area of ​​structure 200 illuminated in point S9. Therefore, Figure 10 When S(S10)-S(S9) shown in the figure become positive, it is possible to detect that the oscillation angle of the first direction X of the movable reflector 120 is less than the oscillation angle in the reference state.

[0080] Figure 13 In point S10, the area of ​​structure 200 illuminated is smaller than the area of ​​structure 200 illuminated in point S9. Therefore, Figure 10 When S(S10)-S(S9) shown in the figure become negative, it is possible to detect that the oscillation angle of the first direction X of the movable reflector 120 is greater than the oscillation angle in the reference state.

[0081] For example, the difference between the first reference received value at point S9 (ninth point) and the second reference received value at point S10 (tenth point) can be set to zero. Figure 9 and Figure 10 In this context, the first reference received value refers to the received value S(S9) under reference conditions, and the second reference received value refers to the received value S(S10) under reference conditions. Additionally, Figure 10 In this context, the reference state can be set in such a way that S(S10)-S(S9) becomes zero. If the oscillation angle of the second direction Y of the movable reflector 120 changes compared to the oscillation angle of the second direction Y of the movable reflector 120 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 in such a way that S(S10)-S(S9) is restored to zero.

[0082] Figures 9-13 The example illustrates the use of points S9 and S10. However, the use of points S11 and S12 also differs from the use of... Figures 9-13 The same applies to the examples that have been explained.

[0083] Figure 14A diagram illustrating an example of the relationship between the oscillation angle of the second direction Y of the movable reflector 120 and the received value S(S11) of the signal generated at the receiving unit 130 from the eleventh point S11 and the received value S(S12) of the signal generated at the receiving unit 130 from the twelfth point S12, i.e., S(S11)-S(S12).

[0084] Figure 14 In the graph, the horizontal axis represents the oscillation angle of the movable reflector 120 in the second direction Y. The vertical axis represents the difference between the received value S(S11) of the signal generated at the eleventh point S11 in the receiving unit 130 and the received value S(S12) of the signal generated at the twelfth point S12 in the receiving unit 130, i.e., S(S11)-S(S12).

[0085] Figure 15 A diagram illustrating an example of the relationship between structure 200, point S9, point S10, point S11, and point S12 in the baseline state. Figure 16 The diagram illustrates an example of the relationship between the structure 200, the ninth point S9, the tenth point S10, the eleventh point S11, and the twelfth point S12 when the oscillation angle of the second direction Y of the movable reflector 120 is less than the oscillation angle in the reference state. Figure 17 The diagram illustrates an example of the relationship between the structure 200, the ninth point S9, the tenth point S10, the eleventh point S11, and the twelfth point S12 when the oscillation angle of the first direction X of the movable reflector 120 is greater than the oscillation angle in the reference state. Figures 15-17 In the diagram, the direction of vibration of the first direction X of the movable reflector 120 is indicated by the double-headed arrows at points S9 and S10 and at points S11 and S12.

[0086] Figures 15-17 In point S9, the area of ​​structure 200 illuminated by the light is substantially equal to the area of ​​structure 200 illuminated by the light in point S10.

[0087] Figure 16 The difference between the area of ​​structure 200 illuminated in point eleven (S11) and the area of ​​structure 200 illuminated in point twelfth (S12) is less than Figure 15 The difference between the area of ​​structure 200 illuminated in point eleven (S11) and the area of ​​structure 200 illuminated in point twelfth (S12). Therefore, as... Figure 14As shown, the difference S(S11)-S(S12) when the oscillation angle of the movable reflector 120 in the second direction Y is less than the difference S(S11)-S(S12) in the reference state is also less 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 in a way that restores the difference S(S11)-S(S12) to the difference S(S11)-S(S12) in the reference state.

[0088] Figure 17 The difference between the area of ​​structure 200 illuminated in point eleven (S11) and the area of ​​structure 200 illuminated in point twelfth (S12) is greater than [missing information]. Figure 15 The difference between the area of ​​structure 200 illuminated in point eleven (S11) and the area of ​​structure 200 illuminated in point twelfth (S12). Therefore, as... Figure 14 As shown, the difference S(S11)-S(S12) when the oscillation angle of the movable reflector 120 in the second direction Y is greater than the difference S(S11)-S(S12) in the reference state is also greater. In this case, the correction unit 150 can correct the detection result of the detection unit 122 in a way that restores the difference S(S11)-S(S12) to the difference S(S11)-S(S12) in the reference state.

[0089] The embodiments and variations have been described above with reference to the accompanying drawings, but these are merely examples of the present invention, and various other configurations may also be employed.

[0090] For example, in this embodiment, the sensor device 10 is a coaxial LiDAR. However, the sensor device 10 can also be a biaxial LiDAR.

[0091] This application claims priority based on Japanese Patent Application No. 2020-062799, filed on March 31, 2020, the entire contents of which are hereby incorporated.

[0092] Explanation of reference numerals in the attached figures

[0093] 10 Sensor Devices

[0094] 110 Ejection section

[0095] 120 Movable Reflector

[0096] 122 Testing Department

[0097] 130 Receiving Department

[0098] 140 beam splitter

[0099] 150 Correction Department

[0100] 162 First Adjustment Department

[0101] 164 Second Adjustment Department

[0102] 200 Constructs

[0103] L scan line

[0104] S1 First point

[0105] S2 Second Point

[0106] S3 Third point

[0107] S4 Fourth point

[0108] S5 Point 5

[0109] S6 Sixth Point

[0110] S7 Point 7

[0111] S8 Point 8

[0112] S9 Ninth Point

[0113] S10, Point 10

[0114] S11, point eleven

[0115] S12, point twelve

[0116] X First Direction

[0117] Y Second Direction

Claims

1. A sensor apparatus comprising: a movable reflection section that reflects electromagnetic waves into a prescribed scanning range; a detection section that detects an oscillation angle of the movable reflection section; a reception section that receives the electromagnetic waves reflected or scattered by a structure located in the scanning range; and a correction section that corrects a detection result of the detection section based on a reception result of the electromagnetic waves reflected by the structure received by the reception section, wherein the correction section corrects the detection result of the detection section based on a relationship between a first reception value received by the reception section of the electromagnetic waves reflected or scattered by a first portion of the structure and a second reception value received by the reception section of the electromagnetic waves reflected or scattered by a second portion of the structure, and wherein the relationship between the first reception value and the second reception value is at least one of a difference between the first reception value and the second reception value and a ratio of the first reception value to the second reception value.

2. The sensor apparatus according to claim 1, wherein the correction section corrects the detection result of the detection section based on a comparison result of the relationship between the first reception value and the second reception value and a relationship between a first reference reception value and a second reference reception value, the first reference reception value being a reference reception value received by the reception section of the electromagnetic waves reflected or scattered by the first portion of the structure when the detection section is operated in a reference state, and the second reference reception value being a reference reception value received by the reception section of the electromagnetic waves reflected or scattered by the second portion of the structure when the detection section is operated in the reference state.

3. The sensor apparatus according to claim 2, further comprising a first adjustment section, wherein the first adjustment section adjusts a position of the structure in such a manner that the relationship between the first reference reception value and the second reference reception value becomes a prescribed reference relationship.

4. The sensor apparatus according to claim 2 or 3, wherein the movable reflection section reflects the electromagnetic waves emitted from an emission section toward the scanning range, and wherein the sensor apparatus further comprises a second adjustment section that adjusts an emission timing of the electromagnetic waves from the emission section in such a manner that the relationship between the first reference reception value and the second reference reception value becomes a prescribed reference relationship.

5. The sensor apparatus according to any one of claims 1 to 3, wherein the first portion and the second portion of the structure are offset in a direction of linear driving of the movable reflection section.

6. The sensor apparatus according to any one of claims 1 to 3, wherein the first portion and the second portion of the structure are offset in a direction of resonance driving of the movable reflection section.

7. The sensor apparatus according to any one of claims 1 to 3, wherein the structure is located outside an area formed by scanning lines of the movable reflection section.

8. The sensor apparatus according to any one of claims 1 to 3, wherein the structure intersects the scanning lines of the movable reflection section. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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