JP7743653B2 - Light control device, light control method, and program - Google Patents

Description

The present invention relates to a light control device that controls the transition of emitted light.

Lidar (LIDAR) is known to detect point clouds on an object's surface by scanning horizontally while intermittently emitting laser light and receiving the reflected light. Patent Document 1 describes a method in which a lidar mounted on an automobile scans the surroundings in one or two dimensions to detect information about the situation around the automobile.

JP 2014-89691 A

If you want to obtain information about the surrounding environment in three dimensions, you need to use a multi-layered lidar. However, multi-layered lidars require the same number of optical transmitters and receivers as the layers, making them very expensive.

The above is an example of a problem 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/receiver.

The invention described in claim 1 is a light control device comprising: a light transmitting/receiving unit installed on a moving object and including an emitting unit that emits light and a light receiving unit that receives the light; and a control unit that controls the transition of the emission angle of the light from the emitting 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 emitting unit in the second direction by a predetermined angle when the emission angle of the light from the emitting 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 emitting unit in the second direction when the emission angle of the light in the first direction is outside the predetermined angle range.

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 emitting unit that emits light and a light receiving unit that receives light reflected by objects around the moving body, the method including a control step of controlling the transition of the emission angle of the light from the emitting unit in all directions in a first direction and in a second direction intersecting the first direction, wherein the control step continuously transitions the light in the first direction while transitioning the emission angle of the light from the emitting unit in the second direction by a predetermined angle when the emission angle of the light from the emitting 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 emitting unit in the second direction when the emission angle of the light in the first direction is outside the predetermined angle range.

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 emitting unit that emits light and a light receiving unit that receives light reflected by objects around the moving body, and a computer. The program causes the computer to function as a control unit that controls the transition of the emission angle of the light from the emitting unit in all directions in 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 emitting unit in the second direction by a predetermined angle when the emission angle of the light from the emitting 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 emitting unit in the second direction when the emission angle of the light in the first direction is outside the predetermined angle range.

The invention described in claim 4 is a light control device comprising: a light transmitting/receiving unit installed on a moving body and including an emitting 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 driving angle of the scanning unit to transition 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 set by the scanning unit is within a predetermined angle range, while transitioning the emission angle of the light in the second direction set 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, without transitioning the emission angle of the light from the emitting unit in the second direction.

FIG. 2 is a block diagram showing the configuration of a rider unit according to the embodiment. FIG. 2 is a block diagram showing the configuration of an optical transmitting and receiving unit. 3 shows waveforms of a trigger signal and a segment extraction signal. 3A and 3B show schematic diagrams of the operation of the omnidirectional scanning unit. 3 shows the trajectory of a spiral scan according to the first embodiment. 1 shows a scanning field of view by spiral scanning in the first embodiment. 10 shows the trajectory of partial multilayer scanning according to the second embodiment.

In a preferred embodiment of the present invention, the light control device comprises: 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 control unit that 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.

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

One aspect of the above light control device further includes a first acquisition unit that acquires first angle information indicating the 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 the 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 trajectory of the emitted light to be spiral based on the first angle information and the second angle information.

In another aspect of the above 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. This allows the same control to be repeated from the reference angle.

Another aspect of the above light control device further includes a detection unit that detects at least one of the distance and angle to the target object based on the light reception results of the light receiving unit. This makes it possible to obtain circular information about the surrounding area of the moving object.

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

In another preferred embodiment of the present invention, 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 emitter that emits light and a light receiver that receives light reflected by objects around the moving body includes a control step of controlling the emitter so that the transition locus of the light emitted by the emitter is spiral by continuously transitioning the light emitted by the emitter between a first direction and a second direction intersecting 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 emitter between the first direction and the second direction.

In another preferred embodiment of the present invention, a program executed by a light control device equipped with a computer and a light transmitting/receiving unit installed on a moving body, the light transmitting/receiving unit having an emitter that emits light and a receiver that receives light reflected by objects around the moving body, causes the computer to function as a control unit that controls the emitter so that the transition trajectory of the light emitted by the emitter is spiral by continuously transitioning the light emitted by the emitter between a first direction and a second direction intersecting the first direction. Executing this program and continuously transitioning the light emitted from the emitter in the first direction and the second direction makes it possible to detect objects around the moving body in three dimensions.

In another preferred embodiment of the present invention, the light control device comprises: 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 control unit that controls the emitting unit so that the light emitted by the emitting unit traces a spiral trajectory on a predetermined plane in space by continuously transitioning the light between a first direction and a second direction intersecting the first direction.

The above-mentioned light control device is installed on a mobile body and includes a light transmitting/receiving unit having an emitting unit and a receiving unit. The emitting unit emits light, and the receiving unit receives light reflected by objects around the mobile body. The control unit controls the emitting unit so that the light emitted by the emitting unit traces a spiral trajectory on a predetermined plane in space by continuously transitioning the light emitted from the emitting unit between a first direction and a second direction intersecting the first direction. In this way, by continuously transitioning the light emitted from the emitting unit between the first direction and the second direction, it becomes possible to detect objects around the mobile body in three dimensions.

In another preferred embodiment of the present invention, the light control device comprises a light transmitting/receiving unit installed on a moving body and including an emitting unit that emits light and a light receiving unit that receives the light, and a control unit that performs first control to continuously transition the light in a first direction and second control to continuously transition the light in a second direction intersecting the first direction, and when the emission angle of the light from the emitting unit in the first direction reaches a predetermined angle, the control unit continuously transitions the light in the first direction while transitioning the emission angle of the light from the emitting unit in the second direction by the predetermined angle.

The light control device is installed on a mobile body and includes a light transmitting/receiving unit having an emitter and a receiver. The emitter emits light, and the receiver receives light reflected by objects around the mobile body. The controller performs a first control that continuously transitions the light emitted by the emitter in a first direction, and a second control that continuously transitions the light in a second direction intersecting the first direction. When the emission angle of the light from the emitter in the first direction reaches a predetermined angle, the controller continuously transitions the light in the first direction while transitioning the emission angle of the light from the emitter in the second direction by the predetermined angle. In this way, by continuously transitioning the light emitted from the emitter in the first and second directions, it is possible to detect objects around the mobile body in three dimensions.

Preferred embodiments of the present invention will now be described with reference to the drawings.
[composition]
1 is a block diagram showing the configuration of a LIDAR unit 100 according to an embodiment. The LIDAR unit 100 of the embodiment is a TOF (Time Of Flight) LIDAR (Light Detection and Ranging or Laser Illuminated Detection and Ranging) that measures the distance to an object (target) 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.

The optical transmitter/receiver 1 includes a laser diode and generates laser pulses PL, which are supplied to the omnidirectional scanning unit 3. The omnidirectional scanning unit 3 emits laser pulses (hereinafter also referred to as "transmitted light pulses Pt") in all 360° horizontal directions while changing the emission direction vertically. The omnidirectional scanning unit 3 emits transmitted light pulses Pt for each segment (900 segments in this embodiment) that divides the 360° horizontal direction at equal angles. Furthermore, the omnidirectional scanning unit 3 receives reflected light of the transmitted light pulses Pt (hereinafter also referred to as "received light pulses Pr") within a predetermined period after emitting the transmitted light pulses Pt, and supplies the reflected light to the optical transmitter/receiver 1. The optical transmitter/receiver 1 generates a signal (hereinafter also referred to as "segment signal Sseg") indicating the intensity of received light for each segment based on the received light pulses Pr, and outputs the signal to the signal processing unit 2.

The signal processing unit 2 outputs surrounding environment information including at least one of the distance to an object or the angle of the object based on the segment signal Sseg for each segment received from the optical transceiver unit 1. The surrounding environment information is information that indicates the surrounding environment of the vehicle on which the lidar unit 100 is mounted, and specifically, information that indicates the distance and angle of objects present in all directions around the vehicle.

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 these to the signal processing unit 2. Based on the horizontal angle θ and vertical angle φ detected by the scan angle detection unit 5, the signal processing unit 2 generates a target horizontal angle θt and a target vertical angle φt as control targets, and supplies these to the scan angle control unit 4. The scan angle control unit 4 controls the scan angle of the transmission light pulse Pt emitted 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.

Next, the optical transmitter/receiver 1 will be described in detail. The configuration of the optical transmitter/receiver 1 is shown in Figure 2. The optical transmitter/receiver 1 mainly comprises 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 transmitter/receiver 1 is an example of the "light transmitting/receiving unit" in this invention.

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 assumed to be 1.8 GHz, as an example. Hereinafter, the clock indicated by the clock signal S1 will also be referred to as the "sample clock."

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

The LD driver 12 sends a pulse current to the laser diode 13 in synchronization with the 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 approximately 5 nsec.

The light pulses emitted from the laser diode 13 are sent to the omnidirectional scanning unit 3 via an optical system. The omnidirectional scanning unit 3 emits transmitted light pulses Pt and receives light pulses reflected by the target as received light pulses Pr, which are sent to the light-receiving element 16. The laser diode 13 is an example of an "emitting unit" in the present invention.

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

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.

The segmentator 19 generates, as the segment signal Sseg, a digital signal that is the output of the A/D converter 18 for 2048 sample clocks during the period of 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.

Figure 3 shows the time-series waveforms of the trigger signal S2 and segment extraction signal S3. As shown in Figure 3, in this embodiment, the segment period, which is the period of one cycle during which the trigger signal S2 is asserted, is set to a length of 131072 sample clocks (denoted 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.

In this case, the segment extraction signal S3 is asserted for only the period of gate width Wg after the trigger signal S2 is asserted, so 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 measurement distance (measurement limit distance) from the rider unit 100.

Next, the omnidirectional scanning unit 3 will be described in detail. The omnidirectional scanning unit 3 is composed of a rotatable mirror and optical system for scanning the transmitted light pulse Pt over a 360° range, for example. The direction in which the omnidirectional scanning unit 3 transmits and receives light pulses relative to the surrounding environment (hereinafter also referred to as the "emission direction") is determined by the horizontal angle θ and the vertical angle φ. Figure 4 shows an example of a scanning state performed by the omnidirectional scanning unit 3. Figure 4(A) is a perspective view showing the omnidirectional scanning unit 3 performing horizontal scanning. Figure 4(B) is a plan view of the scanning state of the omnidirectional scanning unit 3 viewed from above. The light pulse is scanned at a horizontal angle θ relative to a predetermined horizontal reference axis. The horizontal angle θ varies 360° ([deg]) with respect to the horizontal reference axis. In other words, the light pulse can scan in all directions (0° to 360°). Figure 4(C) shows the omnidirectional scanning unit 3 scanning upward from the horizontal scanning state shown in Figure 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 this invention.

[Scanning Control]
(First Example)
Next, an example 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 example described below, the omnidirectional scanning unit 3 performs spiral scanning of seven layers (number of layers n=7) in the vertical direction.

Figure 5 shows the trajectory of spiral scanning in the first embodiment. Figure 5(A) is a perspective view of the trajectory of spiral scanning, Figure 5(B) is a plan view of the trajectory of spiral scanning, and Figure 5(C) is a side view of the trajectory of spiral scanning. Note that Figure 5 shows the trajectory created by a certain point in the emission direction of the transmitted light pulse Pt due to scanning by the omnidirectional scanning unit 3. In other words, Figure 5 shows the trajectory drawn on a specified plane in space by the transmitted light pulse Pt emitted by the omnidirectional scanning unit 3.

As shown in the figure, one spiral scan (one frame) by the omnidirectional scanning unit 3 begins at a start point S, spirals through seven layers (seven turns), reaches an end point E, and then returns to the start point S. The omnidirectional scanning unit 3 repeats this spiral scan. Specifically, during one frame of spiral scanning, the horizontal angle θ changes from 0° to 360° seven times. During this time, the vertical angle φ changes at a constant rate from a vertical angle −φ ₀ at the start point S to a vertical angle φ ₀ 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 start point S is called the “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.

Next, the scanning field of view will be explained. Figure 6(A) shows the horizontal field of view of spiral scanning. In this embodiment, of the 360° omnidirectional scanning, the vertical angle transition range is set to 90°, and the remaining 270° is set to the "effective horizontal field of view angle range θ ₁ ". In other words, θ ₁ = 270°. The effective horizontal field of view angle range is the range obtained by excluding the vertical angle transition range from the 360° omnidirectional scanning, and is the range in which effective segment data can be obtained from the received optical pulse Pr. Now, assuming that 360° scanning by the omnidirectional scanning unit 3 corresponds to 900 segments,
The number of segments per turn is 900/number of layers. The horizontal angular resolution Δθ is
Δθ=360/900=0.4°/seg
This becomes:

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

In spiral scanning, if the vertical angle φ is changed from the negative side to the positive side, the vertical angle φ=−φ ₀ =−15° at time t=0. In addition, if 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 rotates the transmitted light pulse Pt at an angular velocity ω:
ω=2π×15.26×7=3846deg/s
Scan with.

If the time elapsed after the start of the spiral scan is "t", the horizontal angle can be calculated as follows:
The horizontal angle θ shown in equation (1) is the cumulative horizontal angle along the rotation of the spiral, and the horizontal angle θ′ shown in equation (2) is the horizontal angle when the trajectory of the spiral scan is viewed horizontally as shown in Figure 5(B).

Furthermore, if the number of layers in the spiral scan is n, the vertical angle at the starting point is φ ₀ =−15°, the coefficient K is 0.1389, and the effective horizontal field of view angle range is θ ₁ =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.
As described above, in the first embodiment, the omnidirectional scanning unit 3 can acquire three-dimensional segment data by performing spiral scanning of multiple layers with the transmitted light pulse Pt.

(Second Example)
In the spiral scanning of the first embodiment, the vertical angle φ of the emission direction of the transmitted light pulse Pt is changed spirally 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 the vertical angle φ is gradually changed, and therefore, it may be difficult to use this data for subsequent signal processing in the signal processing unit 2.

In contrast, in the scanning of the second embodiment, the vertical angle φ is transitioned for each layer. That is, the omnidirectional scanning unit 3 increases the vertical angle φ for each layer within the vertical angle transition range, and moves the scanning direction to the next layer. Scanning according to this second embodiment is also called "partial multilayer scanning."

Figure 7 shows the trajectory of partial multi-layer scanning in the second embodiment. Figure 7(A) is a perspective view of the trajectory of partial multi-layer scanning, Figure 7(B) is a plan view of the trajectory of partial multi-layer scanning, and Figure 7(C) is a side view of the trajectory of partial multi-layer scanning. Note that Figure 7 shows the trajectory created by a point in the emission direction of the transmitted light pulse Pt due to scanning by the omnidirectional scanning unit 3.

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 field of view angle of each layer (θ = θ ₁ = 270°). Then, in the subsequent vertical angle transition range, the omnidirectional scanning unit 3 increases the vertical angle φ and moves the emission direction to the next layer up. The omnidirectional scanning unit 3 performs such scanning in each layer.

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

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 scans each layer in this manner, and when the emission direction reaches the end point E7 of the top layer (seventh layer), it 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, just as in the spiral scanning of the first embodiment. Then, scanning of the next frame continues in the same manner from the start point S1 of the bottom layer.

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.

In the second embodiment, if the time elapsed after the start of partial multilayer scanning is "t", the horizontal angle can be calculated as follows.
The horizontal angle θ shown in equation (5) is the cumulative horizontal angle along the rotation of the spiral, and the horizontal angle θ′ shown in equation (6) is the horizontal angle when the trajectory of the spiral scan is viewed horizontally as shown in Figure 5(B).

Furthermore, if the number of layers in partial multi-layer scanning is n, the vertical angle φ ₀ at the start point is −15°, and the effective horizontal viewing angle range θ ₁ is 270°, then the vertical angle φ can be calculated as follows:
The function "floor (argument)" in equation (7) indicates the layer being scanned by the transmitted light pulse Pt, and its value is the "integer part of the argument." For example, when the first layer is being scanned, floor(0) = 0. Furthermore, equation (8) indicates the vertical angle φ within the vertical angle transition range of each layer, and equation (9) indicates the vertical angle φ during the transition from the end point E7 to the start point S1.

In the second embodiment, the omnidirectional scanning unit 3 can acquire three-dimensional segment data by performing partial multilayer scanning with the transmitted light pulse Pt. Furthermore, in the second embodiment, multilayer scanning with a constant vertical angle φ can be achieved within the effective horizontal field of view angle range outside the vertical angle transition range, making it possible to obtain segment data with the vertical angle φ fixed.

[Modification]
In the above embodiment, the number of layers in the spiral scan or partial multilayer scan is seven, but this is merely an example, and scanning can be performed with any number of layers. Also, in the above embodiment, the emission direction is shifted by increasing the perpendicular angle φ from the bottom layer to the top layer, but instead, the emission direction may be shifted by decreasing the perpendicular angle φ from the top layer to the bottom layer.

This invention can be used in technology that acquires information about the surrounding environment by emitting laser light.

REFERENCE SIGNS LIST 1 Optical transmitting/receiving unit 2 Signal processing unit 3 Omnidirectional scanning unit 4 Scanning angle control unit 5 Scanning angle detection unit 13 Laser diode 16 Light receiving element

Claims (4)

a light transmitting/receiving unit that is installed on the moving body and includes an emitting 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 a second direction intersecting the first direction;
Equipped with
The control unit continuously shifts the light in the first direction while shifting 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 shifts the light in the first direction while not shifting 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. A light control method executed by a light control device that is installed on a moving body and that includes a light transmitting/receiving unit having an emitting unit that emits light and a light receiving unit that receives light reflected by an object around the moving body,
a control step of performing 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,
a control step of continuously shifting the light in the first direction while shifting 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 shifting the light in the first direction while not shifting 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. 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 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 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. a light transmitting/receiving unit that is installed on the moving body and includes an emitting 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 shifts 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 shifting the emission angle of the light in the second direction by the scanning unit by a predetermined angle, and continuously shifts 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 shifting the emission angle of the light from the emission unit in the second direction.