Light control device, light control method, and program

Abstract

To provide a light control device that makes it possible to obtain three-dimensional information using a single transmitter / receiver.SOLUTION: A light control device is installed on a moving body and includes a light transmitting / receiving unit having an emitting unit and a light receiving unit. The emitting unit emits light, and the light receiving unit receives light reflected by an object around the moving body. The control unit controls the emitting unit so that the transition locus of the light emitted by the emitting unit is spiral by continuously transitioning the light emitted by the emitting unit between a first direction and a second direction intersecting the first direction.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a light control device that controls the transition of emitted light. [Background technology]

[0002] A LIDAR is known that detects a point cloud on an object surface by scanning the horizontal direction while intermittently emitting a laser beam and receiving the reflected light. Patent Document 1 describes a method of detecting information about the situation around the vehicle by scanning the surroundings in one or two dimensions using a LIDAR mounted on the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-89691 A Summary of the Invention [Problem to be solved by the invention]

[0004] To obtain information about the surroundings in three dimensions, a multi-layered lidar must be used, but this requires the same number of optical transmitters and receivers as the layers, which makes the cost very high.

[0005] The above are examples of problems that the present invention aims to solve. The present invention aims to provide a light control device that makes it possible to obtain three-dimensional information using a single transmitter and receiver. [Means for solving the problem]

[0006] The invention described in claim 1 is a light control device comprising: a light transmitting / receiving unit installed on a moving body and having an emission unit that emits light and a light receiving unit that receives the light; and a control unit that controls transition of the emission angle of the light from the emission unit in all directions in a first direction and in a second direction intersecting the first direction, wherein the control unit continuously transitions the light in the first direction while transitioning the emission angle of the light from the emission unit in the second direction by a predetermined angle when the emission angle of the light from the emission unit in the first direction is within a predetermined angle range, and continuously transitions the light in the first direction while not transitioning the emission angle of the light from the emission unit in the second direction when the emission angle of the light in the first direction is outside the predetermined angle range.

[0007] The invention described in claim 2 is a light control method executed by a light control device installed on a moving body and equipped with a light transmitting / receiving unit having an emission unit that emits light and a light receiving unit that receives light reflected by objects around the moving body, the method including a control process for controlling the transition of the emission angle of the light from the emission unit in all directions in a first direction and in a second direction intersecting the first direction, the control process being characterized in that when the emission angle of the light from the emission unit in the first direction is within a predetermined angle range, the light is continuously transitioned in the first direction while the emission angle of the light from the emission unit in the second direction is transitioned by a predetermined angle, and when the emission angle of the light in the first direction is outside the predetermined angle range, the light is continuously transitioned in the first direction while the emission angle of the light from the emission unit in the second direction is not transitioned.

[0008] The invention described in claim 3 is a program executed by a light control device including a light transmitting / receiving unit installed on a moving body and having an emission unit that emits light and a light receiving unit that receives light reflected by objects around the moving body, and a computer, wherein the program causes the computer to function as a control unit that controls the transition of the emission angle of the light from the emission unit in all directions in a first direction and in a second direction intersecting the first direction, and the control unit continuously transitions the light in the first direction while transitioning the emission angle of the light from the emission unit in the second direction by a predetermined angle when the emission angle of the light from the emission unit in the first direction is within a predetermined angle range, and continuously transitions the light in the first direction while not transitioning the emission angle of the light from the emission unit in the second direction when the emission angle of the light in the first direction is outside the predetermined angle range.

[0009] The invention described in claim 4 is a light control device comprising: a light transmitting / receiving unit installed on a moving body and having an emission unit that emits light and a light receiving unit that receives the light; a scanning unit that scans the emitted light; and a control unit that controls the transition of the drive angle of the scanning unit in all directions in a first direction and in a second direction intersecting the first direction, wherein the control unit continuously transitions the light in the first direction when the emission angle of the light in the first direction by the scanning unit is within a predetermined angle range, while transitioning the emission angle of the light in the second direction by the scanning unit by a predetermined angle, and continuously transitions the light in the first direction when the emission angle of the light in the first direction is outside the predetermined angle range, and does not transition the emission angle of the light from the emission unit in the second direction. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a block diagram showing a configuration of a rider unit according to the embodiment. [Diagram 2] FIG. 2 is a block diagram showing a configuration of an optical transmitting / receiving unit. [Diagram 3] 4 shows waveforms of a trigger signal and a segment extraction signal. [Figure 4] 3 illustrates the operation of an omnidirectional scanning unit. [Diagram 5] 4 shows a trajectory of a spiral scan according to the first embodiment. [Figure 6] 3 shows a scanning field of view by spiral scanning in the first embodiment. [Figure 7] 13 shows the trajectory of partial multi-layer scanning according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] In a preferred embodiment of the present invention, a light control device includes a light transmitting / receiving unit that is installed on a moving body and has an emission unit that emits light and a light receiving unit that receives light reflected by an object around the moving body, and a control unit that controls the emission unit so that the transition trajectory of the light emitted by the emission unit becomes spiral by continuously transitioning the light emitted by the emission unit between a first direction and a second direction intersecting the first direction.

[0012] The light control device is installed on a moving body and includes a light transmitting / receiving unit having an emission unit and a light receiving unit. The emission unit emits light, and the light receiving unit receives the light reflected by an object around the moving body. The control unit controls the emission unit so that the transition locus of the light emitted by the emission unit is spiral by continuously transitioning the light emitted by the emission unit between a first direction and a second direction intersecting the first direction. In this way, by continuously transitioning the light emitted from the emission unit between the first direction and the second direction, it is possible to detect objects around the moving body in three dimensions.

[0013] One aspect of the above light control device further includes a first acquisition unit that acquires first angle information indicating an emission angle of the light emitted by the emission unit in the first direction, and a second acquisition unit that acquires second angle information indicating an emission angle of the light emitted by the emission unit in the second direction, and the control unit performs the control based on the first angle information and the second angle information. In this aspect, the control unit controls the transition locus of the emitted light to be spiral based on the first angle information and the second angle information.

[0014] In another aspect of the light control device, when the second angle becomes a predetermined angle, the control unit controls the emission unit so that the first angle and the second angle each become a reference angle within a predetermined time, thereby making it possible to repeat the same control from the reference angle.

[0015] According to another aspect of the present invention, the light control device further includes a detection unit that detects at least one of a distance and an angle to the object based on a light receiving result of the light receiving unit, thereby obtaining peripheral circular information of the moving object.

[0016] In a preferred example, the first direction is horizontal, the control unit controls the emission unit so that light is emitted in all directions of the first direction, and the light receiving unit receives light reflected by objects present in all directions of the first direction.

[0017] In another preferred embodiment of the present invention, a light control method implemented by a light control device installed on a moving body and including a light transmitting / receiving unit having an emission unit for emitting light and a light receiving unit for receiving light reflected by an object around the moving body includes a control step of controlling the emission unit so that the transition locus of the light emitted by the emission unit becomes spiral by continuously transitioning the light emitted by the emission unit between a first direction and a second direction intersecting with the first direction. This method also makes it possible to detect objects around the moving body in three dimensions by continuously transitioning the light emitted from the emission unit between the first direction and the second direction.

[0018] In another preferred embodiment of the present invention, a program executed by a light control device including a light transmitting / receiving unit that is installed on a moving body and has an emitting unit that emits light and a light receiving unit that receives light reflected by objects around the moving body, and a computer, causes the computer to function as a control unit that controls the emitting unit so that the transition locus of the light emitted by the emitting unit becomes spiral by continuously transitioning the light emitted by the emitting unit in a first direction and a second direction intersecting with the first direction. By executing this program and continuously transitioning the light emitted from the emitting unit in the first direction and the second direction, it becomes possible to detect objects around the moving body in three dimensions.

[0019] In another preferred embodiment of the present invention, a light control device includes a light transmitting / receiving unit installed on a moving body and having an emission unit that emits light and a light receiving unit that receives light reflected by an object around the moving body, and a control unit that controls the emission unit so that the light emitted by the emission unit traces a spiral trajectory on a specified surface in space by continuously transitioning the light between a first direction and a second direction intersecting the first direction.

[0020] The light control device is installed on a moving body and includes a light transmitting / receiving unit having an emission unit and a light receiving unit. The emission unit emits light, and the light receiving unit receives the light reflected by an object around the moving body. The control unit controls the emission unit so that the light emitted by the emission unit draws a spiral trajectory on a predetermined surface in space by continuously transitioning the light emitted from the emission unit between a first direction and a second direction intersecting with the first direction. In this way, by continuously transitioning the light emitted from the emission unit between the first direction and the second direction, it is possible to detect objects around the moving body in three dimensions.

[0021] In another preferred embodiment of the present invention, a light control device comprises a light transmitting / receiving unit installed on a moving body and having an emission unit for emitting light and a light receiving unit for receiving the light, and a control unit that performs a first control for continuously transitioning the light in a first direction and a second control for continuously transitioning the light in a second direction intersecting the first direction, and when the emission angle of the light from the emission unit in the first direction becomes a predetermined angle, the control unit transitions the emission angle of the light from the emission unit in the second direction by a predetermined angle while continuously transitioning the light in the first direction.

[0022] The light control device is installed on a moving body and includes a light transmitting / receiving unit having an emission unit and a light receiving unit. The emission unit emits light, and the light receiving unit receives the light reflected by an object around the moving body. The control unit performs a first control to continuously transition the light emitted by the emission unit in a first direction, and a second control to continuously transition the light in a second direction intersecting the first direction. When the emission angle of the light from the emission unit in the first direction becomes a predetermined angle, the control unit continuously transitions the light in the first direction while transitioning the emission angle of the light from the emission unit in the second direction by a predetermined angle. In this way, by continuously transitioning the light emitted from the emission unit in the first direction and the second direction, it is possible to detect objects around the moving body in three dimensions. EXAMPLES

[0023] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. [composition] 1 is a block diagram showing a configuration of a lidar unit 100 according to an embodiment. The lidar unit 100 of the embodiment is a TOF (Time Of Flight) type lidar (Lidar: Light Detection and Ranging, or Laser Illuminated Detection And Ranging) and measures distances to objects (target objects) in all directions in the horizontal direction. As shown in the figure, the lidar unit 100 includes an optical transmitter / receiver 1, a signal processor 2, an omnidirectional scanner 3, a scan angle controller 4, and a scan angle detector 5.

[0024] The optical transmitting / receiving unit 1 includes a laser diode and generates a laser pulse PL and supplies it to the omnidirectional scanning unit 3. The omnidirectional scanning unit 3 emits a laser pulse (hereinafter also referred to as a "transmitted optical pulse Pt") in all directions of 360° in the horizontal direction while changing the emission direction vertically. At this time, the omnidirectional scanning unit 3 emits a transmitted optical pulse Pt for each segment (900 segments in this embodiment) obtained by dividing all directions of 360° in the horizontal direction by equal angles. Furthermore, the omnidirectional scanning unit 3 receives reflected light (hereinafter also referred to as a "received optical pulse Pr") of the transmitted optical pulse Pt within a predetermined period after the emission of the transmitted optical pulse Pt, and supplies it to the optical transmitting / receiving unit 1. The optical transmitting / receiving unit 1 generates a signal (hereinafter also referred to as a "segment signal Sseg") related to the received light intensity for each segment based on the received optical pulse Pr, and outputs it to the signal processing unit 2.

[0025] The signal processing unit 2 outputs surrounding environment information including at least one of the distance to the object and the angle of the object based on the segment signal Sseg for each segment received from the optical transmitting and receiving unit 1. The surrounding environment information is information indicating the surrounding environment of the vehicle on which the lidar unit 100 is mounted, and specifically, is information indicating the distance and angle of objects existing in all directions around the vehicle.

[0026] The scan angle detection unit 5 detects the horizontal angle θ and vertical angle φ that indicate the emission direction of the transmission light pulse Pt emitted by the omnidirectional scan unit 3, and supplies them to the signal processing unit 2. The signal processing unit 2 generates a target horizontal angle θt and a target vertical angle φt as control targets based on the horizontal angle θ and vertical angle φ detected by the scan angle detection unit 5, and supplies them to the scan angle control unit 4. The scan angle control unit 4 controls the scan angle of the transmission light pulse Pt by the omnidirectional scan unit 3 based on the target horizontal angle θt and target vertical angle φt supplied from the signal processing unit 2. As a result, the omnidirectional scan unit 3 is controlled to emit the transmission light pulse Pt at the target horizontal angle θt and target vertical angle φ.

[0027] Next, the optical transmitting / receiving unit 1 will be described in detail. The configuration of the optical transmitting / receiving unit 1 is shown in Fig. 2. The optical transmitting / receiving unit 1 mainly includes a crystal oscillator 10, a synchronization control unit 11, an LD driver 12, a laser diode (LD) 13, a light receiving element 16, a current-voltage conversion circuit (transimpedance amplifier) ​​17, an A / D converter 18, and a segmentator 19. The optical transmitting / receiving unit 1 is an example of the "light transmitting / receiving unit" in the present invention.

[0028] The crystal oscillator 10 outputs a pulsed clock signal S1 to the synchronization control unit 11 and the A / D converter 18. In this embodiment, the clock frequency is 1.8 GHz, for example. In the following description, the clock indicated by the clock signal S1 is also called the "sample clock."

[0029] The synchronization control unit 11 outputs a pulse-like signal (hereinafter referred to as "trigger signal S2") to the LD driver 12. In this embodiment, the trigger signal S2 is 131072 (=2 17 ) sample clock period. Hereinafter, the period from when trigger signal S2 is asserted until the next time it is asserted will be referred to as the "segment period." Furthermore, synchronization control unit 11 outputs a signal (hereinafter referred to as the "segment extraction signal S3") to segmentator 19 that determines the timing at which segmentator 19, described later, extracts the output of A / D converter 18. The trigger signal S2 and segment extraction signal S3 are logical signals, and are synchronized as shown in FIG. 3, described later. In this embodiment, synchronization control unit 11 asserts segment extraction signal S3 for a time width of 2048 sample clocks (also referred to as the "gate width Wg").

[0030] The LD driver 12 supplies a pulse current to the laser diode 13 in synchronization with a trigger signal S2 input from the synchronization control unit 11. The laser diode 13 is, for example, an infrared (905 nm) pulse laser, and emits an optical pulse based on the pulse current supplied from the LD driver 12. In this embodiment, the laser diode 13 emits an optical pulse of about 5 nsec.

[0031] The light pulse emitted from the laser diode 13 is sent to the omnidirectional scanning unit 3 via an optical system. The omnidirectional scanning unit 3 emits a transmission light pulse Pt, and receives a light pulse reflected by an object as a reception light pulse Pr, and sends it to the light receiving element 16. The laser diode 13 is an example of an "emitting unit" in the present invention.

[0032] The light receiving element 16 is, for example, an avalanche photodiode, and generates a weak current corresponding to the light amount of the received light pulse Pr guided by the omnidirectional scanning unit 3. The light receiving element 16 supplies the generated weak current to a current-voltage conversion circuit 17. The current-voltage conversion circuit 17 amplifies the weak current supplied from the light receiving element 16, converts it into a voltage signal, and inputs the converted voltage signal to an A / D converter 18.

[0033] The A / D converter 18 converts the voltage signal supplied from the current-voltage conversion circuit 17 into a digital signal based on the clock signal S1 supplied from the crystal oscillator 10, and supplies the converted digital signal to the segmentator 19. Hereinafter, the digital signal generated by the A / D converter 18 for each clock will also be referred to as a "sample." The light-receiving element 16, the current-voltage conversion circuit 17, and the A / D converter 18 are an example of a "light-receiving unit" in the present invention.

[0034] The segmentator 19 generates, as a segment signal Sseg, a digital signal that is the output of the A / D converter 18 for 2048 sample clocks during the period of the gate width Wg during which the segment extraction signal S3 is asserted. The segmentator 19 supplies the generated segment signal Sseg to the signal processing unit 2.

[0035] Fig. 3 shows the waveforms of the trigger signal S2 and the segment extraction signal S3 in time series. As shown in Fig. 3, in this embodiment, the segment period, which is one cycle period during which the trigger signal S2 is asserted, is set to a length of 131072 sample clocks (indicated as "smpclk" in the drawing), the pulse width of the trigger signal S2 is set to a length of 64 sample clocks, and the gate width Wg is set to a length of 2048 sample clocks.

[0036] In this case, since the segment extraction signal S3 is asserted only for the period of the gate width Wg after the trigger signal S2 is asserted, the segmentator 19 extracts 2048 samples output by the A / D converter 18 while the trigger signal S2 is asserted. The longer the gate width Wg, the longer the maximum distance measurement (distance measurement limit distance) from the lidar unit 100.

[0037] Next, the omnidirectional scanning unit 3 will be described in detail. The omnidirectional scanning unit 3 is composed of a rotatable mirror and an optical system for scanning the transmitted light pulse Pt in 360°, for example. The direction in which the omnidirectional scanning unit 3 transmits and receives the light pulse to the surrounding environment (hereinafter also referred to as the "emitting direction") is determined by the horizontal angle θ and the vertical angle φ. FIG. 4 shows an example of the scanning state by the omnidirectional scanning unit 3. FIG. 4(A) is a perspective view showing the state in which the omnidirectional scanning unit 3 is performing horizontal scanning. FIG. 4(B) is a plan view showing the scanning state of the omnidirectional scanning unit 3 from above. The light pulse is scanned at a horizontal angle θ with respect to a predetermined horizontal reference axis. The horizontal angle θ changes by 360° ([deg]) with respect to the horizontal reference axis. That is, the light pulse can scan in all directions (0° to 360°). FIG. 4(C) shows the state in which the omnidirectional scanning unit 3 is scanning above the horizontal scanning state shown in FIG. 3(A). Specifically, the omnidirectional scanning unit 3 scans the light pulse at a vertical angle φ with respect to the vertical reference axis. In this way, the omnidirectional scanning unit 3 is capable of three-dimensional scanning by continuously changing the horizontal and vertical angles. The omnidirectional scanning unit 3 is an example of the "control unit" in the present invention.

[0038] [Scanning control] (First embodiment) Next, an embodiment of scanning control by the omnidirectional scanning unit 3 will be described. The omnidirectional scanning unit 3 performs scanning of multiple layers in the vertical direction. Specifically, in the first embodiment described below, the omnidirectional scanning unit 3 performs spiral scanning of seven layers (number of layers n=7) in the vertical direction.

[0039] Fig. 5 shows the trajectory of the spiral scan in the first embodiment. Fig. 5(A) is a perspective view of the trajectory by the spiral scan, Fig. 5(B) is a plan view of the trajectory by the spiral scan, and Fig. 5(C) is a side view of the trajectory by the spiral scan. Note that Fig. 5 shows a trajectory created by a certain point in the emission direction of the transmission light pulse Pt by the scan of the omnidirectional scanner 3. In other words, Fig. 5 shows a trajectory drawn on a predetermined surface in space by the transmission light pulse Pt emitted by the omnidirectional scanner 3.

[0040] As shown in the figure, one spiral scan (one frame) by the omnidirectional scanning unit 3 starts from a starting point S, goes through seven layers (seven turns) of spiral rotation to an end point E, and then returns to the starting point S. The omnidirectional scanning unit 3 repeats this spiral scan. Specifically, during one frame of spiral scanning, the horizontal angle θ repeats a change from 0° to 360° seven times. During this time, the vertical angle φ changes at a constant rate from a vertical angle -φ0 at the starting point S to a vertical angle φ0 at the end point E. The period during which the emission direction of the transmission light pulse Pt returns from the end point E to the starting point S is called a "vertical angle transition range." The vertical angle transition range is a range for returning the emission direction of the transmission light pulse Pt to a predetermined direction in order to repeat the spiral scan.

[0041] Next, the scanning field of view will be described. Fig. 6(A) shows the horizontal field of view of a spiral scan. In this embodiment, of the omnidirectional 360°, the vertical angle transition range is set to 90°, and the remaining 270° is set to the "effective horizontal field of view angle range θ1". In other words, θ1 = 270°. The effective horizontal field of view angle range is the range obtained by excluding the vertical angle transition range from the omnidirectional 360°, and is the range in which effective segment data can be obtained from the received optical pulse Pr. Now, assuming that the 360° scan by the omnidirectional scanning unit 3 corresponds to 900 segments, Number of segments per turn = 900 / number of layers The horizontal angular resolution Δθ is Δθ=360 / 900=0.4° / seg It becomes.

[0042] Figure 6(B) shows the horizontal field of view of the helical scan. If the number of layers (turns) of the helical scan is n (=7) and the vertical angular resolution of one layer is Δφ=5°, Vertical viewing angle range = (n-1) × Δφ = 30° The vertical angle φ changes in the range of −15°≦φ≦15°.

[0043] In the spiral scan, if the vertical angle φ is changed from the negative side to the positive side, the vertical angle φ=-φ0=-15° at time t=0. In addition, when it is desired to acquire segment data for seven layers at a frame rate of 15.26 Hz, for example, the omnidirectional scanning unit 3 transmits a transmission light pulse Pt at an angular velocity ω: ω=2π×15.26×7=3846deg / s Scan with.

[0044] If the elapsed time after the start of the helical scan is "t", the horizontal angle can be calculated as follows:

number

[0045] In addition, if the number of layers in the spiral scan is n, the vertical angle at the starting point is φ0 = -15°, the coefficient K = 0.1389, and the effective horizontal field of view angle range θ1 = 270°, the vertical angle can be calculated as follows: Equation (3) shows the vertical angle within the effective horizontal field of view angle range, and Equation (4) shows the vertical angle within the vertical angle transition range.

number

[0046] (Second Example) In the spiral scanning of the first embodiment, the vertical angle φ of the emission direction of the transmission light pulse Pt is changed in a spiral shape at a constant rate of change. However, in the spiral scanning of the first embodiment, the data obtained within one layer is data obtained while gradually changing the vertical angle φ, and therefore, it may be difficult to use the data for the subsequent signal processing in the signal processing unit 2.

[0047] In contrast, in the scanning of the second embodiment, the vertical angle φ is changed for each layer. That is, the omnidirectional scanning unit 3 increases the vertical angle φ for each layer in the vertical angle transition range and moves the scanning direction to the next layer. Such scanning according to the second embodiment is also called "partial multi-layer scanning."

[0048] The trajectory of partial multi-layer scanning according to the second embodiment is shown in Fig. 7. Fig. 7(A) is a perspective view of the trajectory of partial multi-layer scanning, Fig. 7(b) is a plan view of the trajectory of partial multi-layer scanning, and Fig. 7(C) is a side view of the trajectory of partial multi-layer scanning. Fig. 7 shows the trajectory of a certain point in the emission direction of the transmission light pulse Pt by the scan of the omnidirectional scanning unit 3.

[0049] As shown in the figure, in the partial multi-layer scanning of the second embodiment, the omnidirectional scanning unit 3 performs scanning without changing the vertical angle φ in the range up to the effective horizontal viewing angle (θ=θ1=270°) of each layer. Then, the omnidirectional scanning unit 3 increases the vertical angle φ in the subsequent vertical angle transition range and moves the emission direction to the next upper layer. The omnidirectional scanning unit 3 performs such scanning in each layer.

[0050] Specifically, as shown in Figures 7(A) and (C), first, the omnidirectional scanning unit 3 scans from the start point S1 to the end point E1 of the bottom layer (first layer) without changing the vertical angle φ, and then, in the vertical angle transition range of the subsequent bottom layer, increases the vertical angle φ by one layer and moves the emission direction to the start point S2 of the second layer.

[0051] Next, the omnidirectional scanning unit 3 scans from the start point S2 to the end point E2 of the second layer without changing the vertical angle φ, and then in the vertical angle transition range of the second layer, increases the vertical angle φ by one layer and moves the emission direction to the start point S3 of the third layer. The omnidirectional scanning unit 3 sequentially performs such scanning for each layer, and when the emission direction reaches the end point E7 of the top layer (seventh layer), moves the vertical angle φ from the end point E7 of the top layer to the start point E1 of the bottom layer in the vertical angle transition range, similar to the spiral scanning of the first embodiment. Then, scanning of the next frame continues from the start point S1 of the bottom layer in the same manner.

[0052] As in the first embodiment, if the number of layers n=7 and the range of the vertical angle φ is -15°≦φ≦15°, the omnidirectional scanning unit 3 will move the emission direction to the next higher layer by increasing the vertical angle φ by 5° within the vertical angle transition range of each layer.

[0053] In the second embodiment, if the elapsed time after the start of partial multi-layer scanning is "t", the horizontal angle can be calculated as follows.

number

[0054] Furthermore, if the number of layers in the partial multi-layer scanning is n, the vertical angle at the start point is φ0=-15°, and the effective horizontal viewing angle range θ1=270°, then the vertical angle φ can be calculated as follows:

number

[0055] In the second embodiment, the omnidirectional scanning unit 3 can obtain three-dimensional segment data by performing partial multi-layer scanning with the transmitted light pulse Pt. Also, in the second embodiment, multi-layer scanning with a constant vertical angle φ can be realized within the effective horizontal viewing angle range other than the vertical angle transition range, and segment data can be obtained with the vertical angle φ fixed.

[0056] [Variations] In the above embodiment, the number of layers in the spiral scan or partial multi-layer scan is seven, but this is only an example, and scanning can be performed with any number of layers. In addition, in the above embodiment, the emission direction is moved from the bottom layer to the upper layer by increasing the perpendicular angle φ, but instead, the emission direction may be moved from the top layer to the lower layer by decreasing the perpendicular angle φ. [Industrial Applicability]

[0057] The present invention can be used in a technique for acquiring surrounding environment information by emitting laser light. [Explanation of symbols]

[0058] 1 Optical transmitter and receiver 2. Signal Processing Section 3 Omnidirectional scanning section 4 Scan angle control section 5 Scanning angle detection unit 13 Laser Diode 16 Photodetector

Claims

1. a light transmitting / receiving unit that is installed on the moving body and includes an emission unit that emits light and a light receiving unit that receives the light; a control unit that performs control to transition an emission angle of the light from the emission unit in all directions of a first direction and in a second direction intersecting the first direction; Equipped with the control unit continuously transitions the light in the first direction while transitioning the emission angle of the light from the emission unit in the second direction by a predetermined angle when the emission angle of the light from the emission unit in the first direction is within a predetermined angle range, and continuously transitions the light in the first direction while transitioning the emission angle of the light from the emission unit in the second direction by a predetermined angle when the emission angle of the light in the first direction is outside the predetermined angle range, and characterized in that

2. A light control method executed by a light control device that is installed on a moving body and has a light transmitting / receiving unit having an emission unit that emits light and a light receiving unit that receives light reflected by an object around the moving body, the method comprising: a control step of controlling an emission angle of the light from the emission unit to transition in all directions of a first direction and in a second direction intersecting the first direction; The light control method is characterized in that the control step continuously transitions the light in the first direction while transitioning the emission angle of the light from the emission unit in the second direction by a predetermined angle when the emission angle of the light from the emission unit in the first direction is within a predetermined angle range, and continuously transitions the light in the first direction while not transitioning the emission angle of the light from the emission unit in the second direction when the emission angle of the light in the first direction is outside the predetermined angle range.

3. A program executed by a light control device including a light transmitting / receiving unit that is installed on a moving body and has an emission unit that emits light and a light receiving unit that receives light reflected by an object around the moving body, and a computer, causing the computer to function as a control unit that performs control to transition an emission angle of the light from the emission unit in all directions of a first direction and in a second direction intersecting the first direction; the control unit continuously transitions the light in the first direction while transitioning the emission angle of the light from the emission unit in the second direction by a predetermined angle when the emission angle of the light from the emission unit in the first direction is within a predetermined angle range, and continuously transitions the light in the first direction while not transitioning the emission angle of the light from the emission unit in the second direction when the emission angle of the light in the first direction is outside the predetermined angle range.

4. a light transmitting / receiving unit that is installed on the moving body and includes an emission unit that emits light and a light receiving unit that receives the light; A scanning unit that scans the emitted light; a control unit that performs control to transition a drive angle of the scanning unit in all directions of a first direction and in a second direction intersecting the first direction; Equipped with The control unit continuously transitions the light in the first direction when the emission angle of the light in the first direction by the scanning unit is within a predetermined angle range, while transitioning the emission angle of the light in the second direction by the scanning unit by a predetermined angle, and continuously transitions the light in the first direction when the emission angle of the light in the first direction is outside the predetermined angle range, while not transitioning the emission angle of the light from the emission unit in the second direction.

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