Distance measuring system, light-emitting device, and light-receiving device

Abstract

To provide a distance measuring system that can be downsized even if a light-emitting surface and a light-receiving surface are split into a plurality of slots.SOLUTION: A distance measuring system includes: a light-emitting portion that emits light; a light-receiving portion that receives reflected light, which is the light from the light-emitting portion and reflected on an object; a control calculation portion that controls the light-emitting portion or the light-receiving portion, and calculates a distance to the object on the basis of time between light-emitting timing of the light-emitting portion and light-receiving timing at which the light-receiving portion receives the light; a first signal line that transmits, from the control calculation portion or the light-receiving portion to the light-emitting portion by serial communication, a light-emitting signal pointing out a light-emitting area in the light-emitting portion; a second signal line that transmits, from the control calculation portion or the light-receiving portion to the light-emitting portion by the serial communication, a first trigger signal indicating the light-emitting timing; a third signal line that transmits, from the control calculation portion or the light-emitting portion to the light-receiving portion by the serial communication, a light-receiving signal pointing out a light-receiving area in the light-receiving portion; and a fourth signal line that transmits, from the control calculation portion or the light-emitting portion to the light-receiving portion by the serial communication, a second trigger signal indicating the light-receiving timing.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a ranging system, a light emitting device, and a light receiving device. [Background technology]

[0002] In a distance measuring device using the ToF (Time of Flight) method, the light emitting surface of a light emitting device and the light receiving surface of a light receiving device are divided into a plurality of slots, and light emission control and light reception control are performed for each slot. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Patent Application Publication No. 2020 / 195898 [Patent Document 2] International Patent Application Publication No. 2022 / 080014 Summary of the Invention [Problem to be solved by the invention]

[0004] However, an increase in the number of slots increases the number of signal lines from the host to the light emitting device and the light receiving device, and also increases the number of connectors in the host, the light emitting device, and the light receiving device, etc. In this case, the size of the distance measuring device increases, leading to an increase in costs.

[0005] In view of the above, an object of the present disclosure is to provide a distance measuring system, a light emitting device, and a light receiving device that can be miniaturized by reducing the number of signal lines from a host to a light emitting device and a light receiving device. [Means for solving the problem]

[0006] A distance measuring system according to one aspect of the present disclosure includes a light emitting unit that emits light, a light receiving unit that receives light reflected from an object, a control calculation unit that controls the light emitting unit or the light receiving unit and calculates a distance to the object based on the time from the light emitting unit's emission timing to the light receiving unit's reception timing, a first signal line that transmits a light emitting signal indicating a light emitting area in the light emitting unit from the control calculation unit or the light receiving unit to the light emitting unit via serial communication, a second signal line that transmits a first trigger signal indicating the light emitting timing from the control calculation unit or the light receiving unit to the light emitting unit via serial communication, a third signal line that transmits a light receiving signal indicating a light receiving area in the light receiving unit from the control calculation unit or the light emitting unit to the light receiving unit via serial communication, and a fourth signal line that transmits the second trigger signal indicating the light receiving timing from the control calculation unit or the light emitting unit to the light receiving unit via serial communication.

[0007] The control calculation unit is serially connected to the light-emitting unit via first and second signal lines, and the light-emitting unit is serially connected to the light-receiving unit via third and fourth signal lines.

[0008] The control calculation unit transmits an emission signal to the light emitting unit via a first signal line, the light emitting unit receives the emission signal and transmits the emission signal to the light receiving unit via a third signal line, and the light receiving unit receives the emission signal from the light emitting unit and converts the emission signal into a light receiving signal.

[0009] The control calculation unit transmits an emission signal to the light emitting unit via a first signal line, the light emitting unit receives the emission signal, converts the emission signal into a light receiving signal, and transmits it to the light receiving unit via a third signal line, and the light receiving unit receives the light receiving signal.

[0010] The control calculation unit transmits a first trigger signal to the light-emitting unit via the second signal line, the light-emitting unit receives the first trigger signal, and transmits the first trigger signal as a second trigger signal to the light-receiving unit via the fourth signal line, and the light-receiving unit receives the second trigger signal.

[0011] The control calculation unit is serially connected to the light receiving unit via third and fourth signal lines, and the light receiving unit is serially connected to the light emitting unit via first and second signal lines.

[0012] The control and calculation unit transmits the received light signal to the light receiving unit via the third signal line, the light receiving unit receives the received light signal and transmits the received light signal to the light emitting unit via the first signal line, and the light emitting unit receives the received light signal and converts it into an light emitting signal.

[0013] The control and calculation unit transmits the received light signal to the light receiving unit via the third signal line, the light receiving unit converts the received light signal into an emission signal and transmits it to the light emitting unit via the first signal line, and the light emitting unit receives the emission signal.

[0014] The control calculation unit transmits a second trigger signal to the light receiving unit via the fourth signal line, the light receiving unit receives the second trigger signal and transmits the second trigger signal as a first trigger signal to the light emitting unit via the second signal line, and the light emitting unit receives the first trigger signal.

[0015] The control calculation unit is serially connected to the light emitting unit and the light receiving unit via first and third signal lines, respectively, and is serially connected to the light emitting unit via a second signal line, and the light receiving unit is serially connected to the light emitting unit via a fourth signal line.

[0016] The control calculation unit transmits an emission signal to the light emission unit via a first signal line, transmits a received light signal to the light reception unit via a third signal line, and transmits a first trigger signal to the light emission unit via the second signal line, the light emission unit receives the first trigger signal and transmits the first trigger signal to the light reception unit as a second trigger signal, and the light reception unit receives the second trigger signal.

[0017] The control calculation unit transmits an emission signal to the light emission unit via a first signal line, transmits a received light signal to the light reception unit via a third signal line, and transmits a second trigger signal to the light reception unit via a fourth signal line, the light reception unit receives the second trigger signal and transmits the second trigger signal as a first trigger signal to the light emission unit, and the light emission unit receives the first trigger signal.

[0018] The light emitting section and the light receiving section are each divided into a plurality of light emitting regions and a plurality of light receiving regions, and the control and calculation section controls the light emitting section for each light emitting region and controls the light receiving section for each light receiving region.

[0019] The device further includes a fifth signal line for transmitting a clock signal from the control and calculation unit or the light receiving unit to the light emitting unit by serial communication, and a sixth signal line for transmitting the clock signal from the control and calculation unit or the light emitting unit to the light receiving unit by serial communication.

[0020] A plurality of light-emitting units are connected in series to enable serial communication, and a plurality of light-receiving units are connected in series to enable serial communication.

[0021] An illumination device according to one aspect of the present disclosure includes a light-emitting unit that emits light, a first interface that receives an illumination signal indicating an illumination area in the light-emitting unit from a control and calculation unit or a light-receiving unit via serial communication, a first buffer that holds the illumination signal, and a second interface that transmits the illumination signal or a light-receiving signal obtained by converting the illumination signal to the light-receiving device via serial communication.

[0022] A light receiving device according to one aspect of the present disclosure includes a light receiving unit that receives reflected light from a light emitting unit that is reflected by an object, a third interface that receives a light receiving signal indicating a light receiving area in the light receiving unit from a control and calculation unit or the light emitting unit via serial communication, a second buffer that holds the light receiving signal, and a fourth interface that transmits the light receiving signal or an emission signal obtained by converting the light receiving signal to the light emitting device via serial communication. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a distance measuring system according to a first embodiment. [Diagram 2] 13 is an example of a histogram of the number of times of light reception according to the present embodiment. [Diagram 3] FIG. 1 is a block diagram showing an example of the configuration of a distance measuring system according to a first embodiment. [Figure 4] 1 is a block diagram showing an example of the configuration of a light emitting device according to a first embodiment. [Diagram 5] FIG. 1 is a block diagram showing an example of the configuration of a light receiving device according to a first embodiment. [Figure 6] FIG. 4 is a timing chart showing an example of the operation of the distance measuring system according to the first embodiment. [Figure 7A] FIG. 4 is a diagram showing an example of a data format of a light emission signal. [Figure 7B] FIG. 4 is a diagram showing an example of a data format of a received light signal. [Figure 8A] FIG. 13 is a conceptual diagram showing the correspondence between light emitting slots and light receiving slots. [Figure 8B] FIG. 13 is a conceptual diagram showing the correspondence between light emitting slots and light receiving slots. [Figure 8C] FIG. 13 is a conceptual diagram showing the correspondence between light emitting slots and light receiving slots. [Figure 9] FIG. 11 is a block diagram showing an example of the configuration of a distance measuring system according to a second embodiment. [Figure 10] FIG. 13 is a block diagram showing an example of the configuration of a distance measuring system according to a third embodiment. [Figure 11] FIG. 13 is a block diagram showing an example of the configuration of a distance measuring system according to a fourth embodiment. [Figure 12] FIG. 13 is a block diagram showing an example of the configuration of a distance measuring system according to a fifth embodiment. [Figure 13] FIG. 13 is a block diagram showing an example of the configuration of a distance measuring system according to a sixth embodiment. [Figure 14] FIG. 13 is a block diagram showing an example of the configuration of a distance measuring system according to a seventh embodiment. [Figure 15] FIG. 1 is a block diagram showing an example of a schematic configuration of a vehicle control system. [Figure 16] FIG. 4 is an explanatory diagram showing an example of the installation positions of an outside-vehicle information detection unit and an imaging unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, specific embodiments to which the present technology is applied will be described in detail with reference to the drawings. The drawings are schematic or conceptual, and the ratios of each part are not necessarily the same as those in reality. In the specification and drawings, elements similar to those described above with respect to the previously mentioned drawings are given the same reference numerals, and detailed descriptions are omitted as appropriate.

[0025] (First embodiment) 1 is a diagram showing a configuration example of a distance measuring system according to a first embodiment. A distance measuring system 300 according to the present disclosure employs a direct ToF (Time Of Flight) method. In the direct ToF method, a light emitting device emits light, and a light receiving device receives the light reflected by an object. The distance measuring device measures distance based on the time difference between the light emission timing and the light reception timing.

[0026] Distance measuring system 300 includes light emitting device 301 and light receiving device 302. Light emitting device 301 is, for example, a laser diode, and is driven to emit pulsed laser light. Light emitted from light emitting device 301 is reflected by an object 303 and received as reflected light by light receiving device 302. Light receiving device 302 includes a light receiving element that converts light into an electrical signal by photoelectric conversion, and outputs a signal corresponding to the received light.

[0027] The time when the light emitting device 301 emits light (light emission timing) is t em The time when the light emitted from the light emitting device 301 is reflected by the object 303 and received by the light receiving device 302 (light receiving timing) is t re , and constant c is the speed of light. In this case, the distance D between the distance measuring system 300 and the object 303 is calculated by Equation 1.

[0028] D = (c / 2) × (t em -t re ) Equation 1 The distance measuring system 300 repeats the above process multiple times. The light receiving device 302 may include multiple light receiving elements, and the distance D may be calculated based on the light receiving timing at which the reflected light is received by each light receiving element. em From the light receiving timing t re Time t until m are classified into classes (bins).

[0029] The light receiving device 302 receives light for a period of time t mThe light received by the light receiving device 302 is not limited to light emitted from the light emitting device 301 and reflected by an object. For example, ambient light around the distance measuring system 300 is also received by the light receiving device 302.

[0030] FIG. 2 is an example of a histogram of the number of times light is received according to this embodiment. In FIG. 2, the horizontal axis represents the light receiving time t m The vertical axis indicates the frequency of light reception (number of received photons) for each bin. m are classified for each unit time d. Specifically, bin #0 is 0≦t m <d、ビン#1がd≦t m < 2 × d, bin #2 is 2 × d ≦ t m < 3 × d, …, bin #(N-2) is (N-2) × d ≦ t m <(N-1)×d. The exposure time of the light receiving device 302 is time t ep In this case, t ep = N × d.

[0031] The distance measurement system 300 measures the number of light receptions (the number of received photons) over a light reception time t m A histogram is generated by displaying the frequency 310 for each bin. The light receiving device 302 receives ambient light in addition to the reflected light of the light emitted from the light emitting device 301. The ambient light is light that is randomly incident on the light receiving device 302, and becomes noise in the reflected light from the target object.

[0032] On the other hand, the reflected light is light received according to the distance from the distance measuring system 300 to the object, and appears in the histogram as an active light component 312. The distance measuring system 300 calculates the representative time of a bin of the active light component 312 (for example, the central time of the bin) as the light receiving timing t re Thus, the distance measuring system 300 can calculate the distance D to the object 303 using Equation 1. In this way, the distance measuring system 300 can perform appropriate distance measurement against random noise.

[0033] 3 is a block diagram showing an example of the configuration of a distance measuring system according to the first embodiment. The distance measuring system 300 includes a host 306, a light emitting device 301, and a light receiving device 302.

[0034] The host 306 as a control calculation unit is, for example, a field programmable gate array (FPGA) or a central processing unit (CPU), and controls the light emitting device 301. The host 306 is connected to the light emitting device 301 via serial communication lines 304a to 304c so as to be able to perform serial communication. The host 306 transmits a clock signal INCK to the light emitting device 301 via the serial communication line 304a. The host 306 transmits a light emission signal INST_TX to the light emitting device 301 via the serial communication line 304b. The host 306 transmits a trigger signal TRG_I to the light emitting device 301 via the serial communication line 304c. The serial communication lines 304a to 304c are communication lines using a serial communication method such as, for example, SPI (Serial Peripheral Interface) or LVDS (Low Voltage Differential Signaling).

[0035] The light emitting signal INST_TX is a command signal that indicates the light emitting area and the number of times of light emission of the light emitting device 301. The trigger signal TRG_I is a signal that indicates the light emitting timing of the light emitting device 301. The clock signal INCK is multiplied by the multiplier 301a and used to generate an internal clock. The light emitting device 301 performs light emitting operations and the like based on the internal clock.

[0036] The light emitting device 301 is, for example, a semiconductor laser device such as a VCSEL (Vertical Cavity Surface Emitting Laser), and includes a light emitting surface configured by arranging a plurality of light emitting elements two-dimensionally. The light emitting surface is divided into a plurality of light emitting regions (hereinafter also referred to as light emitting slots), each of which can emit light at an individual timing. That is, the light emitting device 301 can be controlled for each light emitting slot. The light emitting signal INST_TX includes the address of the light emitting slot to be illuminated and information on the number of times the light emitting slot is to be illuminated. The light emitting device 301 illuminates the light emitting slot specified by the light emitting signal INST_TX for the number of times specified by the light emitting signal INST_TX based on the timing of receiving the trigger signal TRG_I.

[0037] The light emitting device 301 includes a multiplier 301a, a buffer 301b, a buffer 301c, and a trigger processing circuit 301d. The buffers 301b and 301c temporarily hold the light emitting signal INST_TX and the clock signal INCK, and transmit them to the light receiving device 302 via serial communication lines 305b and 305a. The trigger processing circuit 301d receives a trigger signal TRG_I and starts the light emitting operation of the light emitting device 301. The light emitting device 301 transfers the trigger signal TRG_I as a trigger signal TRG_O to the light receiving device 302 via the serial communication line 305c. The multiplier 301a multiplies the clock signal INCK to generate an internal clock. The light emitting device 301 performs a light emitting operation in synchronization with the internal clock.

[0038] The light receiving device 302 is, for example, a light detection device such as a SPAD (Single Photon Avalanche Diode), and includes a light receiving surface configured by arranging a plurality of light receiving elements two-dimensionally. The light receiving surface is divided into a plurality of light receiving regions (hereinafter also referred to as light receiving slots), each of which can receive light at an individual timing. That is, the light receiving device 302 can be controlled for each light receiving slot. The light receiving signal INST_RX includes information on the address of the light receiving slot to receive light and the number of times the light emitting device 301 emits light. The light receiving device 302 operates the light receiving slot designated by the light receiving signal INST_RX to be able to receive light, based on the timing of receiving the trigger signal TRG_O.

[0039] The position of the light-emitting slot and the position of the light-receiving slot that receives the light emitted from the light-emitting slot are almost in correspondence with each other. Therefore, if the light-receiving device 302 associates the address of the light-emitting slot with the address of the corresponding light-receiving slot and stores them in advance in the memory 302e, the light-receiving device 302 can generate the address of the light-receiving slot that should operate correspondingly from the address of the light-emitting slot that emits light. That is, the light-receiving device 302 can generate the light-receiving signal INST_RX from the light-emitting signal INST_TX. Conversely, the light-receiving device 302 can generate the address of the light-emitting slot that should operate correspondingly from the address of the light-receiving slot. That is, the light-receiving device 302 can also generate the light-emitting signal INST_TX from the light-receiving signal INST_RX.

[0040] Furthermore, the trigger signal TRG_O is a trigger signal transmitted from the light emitting device 301 based on the trigger signal TRG_I, and is related to the timing of the trigger signal TRG_I. Therefore, the light receiving device 302 can know the timing at which light is emitted from the light emitting device 301. Therefore, the light receiving device 302 can perform a light receiving operation during the period in which it receives the reflected light reflected from the target object. When the light receiving device 302 receives the clock signal INCK, it multiplies the signal by the multiplier 302a to generate an internal clock. The light receiving device 302 also performs a light receiving operation in synchronization with the internal clock.

[0041] The light receiving device 302 includes a multiplier 302a, a buffer 302b, a light emission signal processing circuit 302c, a trigger processing circuit 302d, and a memory 302e. The buffer 302b holds a clock signal INCK. The memory 302e stores a correspondence between the address of a light emission slot to be emitted and the address of a light reception slot to be operated correspondingly. The light emission signal processing circuit 302c converts the light emission signal INST_TX into a light reception signal INST_RX using the correspondence between the address of the light emission slot and the address of the corresponding light reception slot stored in the memory 302e. The trigger processing circuit 302d starts the light reception operation of the light receiving device 302 upon receiving the trigger signal TRG_O. The multiplier 302a multiplies the clock signal INCK to generate an internal clock. The light receiving device 302 executes a light reception operation in synchronization with the internal clock.

[0042] 4 is a block diagram showing an example of the configuration of the light emitting device according to Embodiment 1. Light emitting device 301 further includes interface IFtx_I, interface IFtx_O, light emission timing adjustment section 315, light emitting area setting section 316, driver 317 and light emitting area 318.

[0043] The interface IFTx_I receives the light emission signal INST_TX, the trigger signal TRG_I, and the clock signal INCK from the host 306 via the serial communication lines 304a to 304c. The interface IFTx_O transmits the clock signal INCK to the light receiving device 302 via the serial communication line 305a. The interface IFTx_O transmits the light emission signal INST_TX to the light receiving device 302 via the serial communication line 305b. The interface IFTx_O transmits the trigger signal TRG_O to the light receiving device 302 via the serial communication line 305c.

[0044] The light emission timing adjustment unit 315 adjusts the timing of the light emission operation in accordance with the reception timing of the trigger signal TRG_I, and transmits a light emission trigger to the driver 317. The light emission timing adjustment unit 315 transmits light emission triggers in the same number as the number of emissions of the light emission signal INST_TX to the driver 317. The light emission timing adjustment unit 315 may be, for example, a programmable logic controller (PLC), an FPGA, a CPU, or the like.

[0045] The light emitting area setting unit 316 designates a light emitting area according to the address of the light emitting slot of the light emitting signal INST_TX. The light emitting area setting unit 316 may be, for example, a PLC, an FPGA, a CPU, or the like.

[0046] Driver 317 drives the light emitting slots of light emitting area 318 set by light emitting area setting unit 316 in accordance with a light emitting trigger from light emitting timing adjustment unit 315. Light emitting area 318 is driven by driver 317 to emit light. Light emitting area 318 is composed of a laser diode such as a VCSEL, for example.

[0047] 5 is a block diagram showing an example of the configuration of the light receiving device according to the first embodiment. The light receiving device 302 further includes an interface IFrx_I, a light receiving timing adjustment unit 325, a light receiving region setting unit 326, a pixel region 327, and a distance measurement processing unit 328.

[0048] The interface IFrx_I receives a light emission signal INST_TX, a trigger signal TRG_I, and a clock signal INCK from the host 306 via serial communication lines 304a to 304c.

[0049] The light-receiving timing adjustment unit 325 adjusts the timing of the start of the light-receiving operation according to the reception timing of the trigger signal TRG_O, and transmits a light-receiving trigger to the pixel region 327. The light-receiving timing adjustment unit 325 determines the light-receiving period according to the number of times the light-emitting device 301 emits light, which is included in the light-receiving signal INST_RX. The light-receiving timing adjustment unit 325 may be, for example, a PLC, an FPGA, a CPU, or the like.

[0050] The light receiving area setting unit 326 designates a light receiving area according to the address of the light receiving slot of the light receiving signal INST_RX. The light receiving area setting unit 326 may be, for example, a PLC, an FPGA, a CPU, or the like.

[0051] The pixel region 327 drives the light receiving element or the light receiving slot including multiple light receiving elements set by the light receiving region setting unit 326 in accordance with a light receiving trigger from the light receiving timing adjustment unit 325. The pixel region 327 starts a light receiving operation after receiving the light receiving trigger, and continues the light receiving operation for a predetermined period determined by the number of times of light emission. The pixel region 327 may be, for example, a light detection device such as a SPAD.

[0052] The distance measurement processing unit 328 calculates the distance D between the distance measurement system 300 and the object 303 using the light emission timing obtained from the light emitting device 301 and the light reception timing of the reflected light detected in the pixel area 327. In this manner, the distance measurement system 300 can measure the distance to the object 303.

[0053] FIG. 6 is a timing chart showing an example of the operation of the distance measuring system according to the first embodiment.

[0054] At t1, the light emitting device 301 receives a light emitting signal INST_TX. The light emitting device 301 sets a light emitting slot and a number of times of light emission designated by the light emitting signal INST_TX. When the light emitting signal INST_TX designates a plurality of light emitting slots, the light emitting area setting unit 316 sets a plurality of light emitting slots. The light emitting timing adjustment unit 315 sets a light emitting trigger according to the number of times of light emission.

[0055] FIG. 7A is a diagram showing an example of a data format of the light emission signal INST_TX. The number of light emission points indicates the number of light emission slots (number of addresses) to be illuminated. The address of the light emission slot to be illuminated includes a horizontal light emission address and a vertical light emission address. For example, when the light emission surface of the light emission device 301 is represented by an XY orthogonal coordinate system, the horizontal light emission address indicates the X coordinate, and the vertical light emission address indicates the Y coordinate. For example, the horizontal light emission address ADDTXH1 and the vertical light emission address ADDTXV1 indicate one light emission slot. The horizontal light emission address ADDTXHn and the vertical light emission address ADDTXVn (n is a positive integer) indicate the nth light emission slot. That is, in FIG. 7A, the light emission signal INST_TX specifies the light emission of n light emission slots. The light emission area setting unit 316 sets the n light emission slots specified by the light emission signal INST_TX to be illuminated. The number of times of light emission indicates the number of times of light emission (number of bursts) of the specified n light emission slots. The End of Frame is data indicating the end point of the light emission signal INST_TX. Note that the Start of Frame may be used instead of the End of Frame. The start of frame is data indicating the start point of the light emission signal INST_TX. The boundary between each light emission signal INST_TX can be determined by either the end of frame or the start of frame. Therefore, it is sufficient that either the end of frame or the start of frame is included in the light emission signal INST_TX. The checksum is data for verifying the accuracy of the light emission signal INST_TX, and may be error code correction data. The checksum can be used to verify the accuracy of the command of the light emission signal INST_TX in order to ensure the safety of the function of the light emitting device 301.

[0056] By using such a light emission signal INST_TX, the light emitting device 301 sets the light emitting area and the number of times of light emission.

[0057] At t2, the light emitting device 301 receives the trigger signal TRG_I. t2 to t8 are delay times from when the trigger signal TRG_I is received until the light emitting slot designated by the light emitting signal INST_TX emits light.

[0058] At t3, when the light emission signal INST_TX is received by the light receiving device 302, the light emission signal processing circuit 302c converts the light emission signal INST_TX into a light reception signal INST_RX using the correspondence between the addresses of the light emission slots and the addresses of the light reception slots.

[0059] At t4, the light receiving device 302 sets a light receiving slot and a light receiving count designated by the light receiving signal INST_RX. If the light receiving signal INST_RX designates multiple light receiving slots, the light receiving region setting unit 326 sets multiple light receiving slots. The light receiving timing adjustment unit 325 sets a light receiving trigger according to the light receiving count.

[0060] 7B is a diagram showing an example of the data format of the light receiving signal INST_RX. The number of light emitting points indicates the number of light emitting slots (number of addresses) to be illuminated. The number of light emitting points also corresponds to the number of light receiving slots to receive light. In other words, the address of the light receiving slot to receive light is set corresponding to the address of the light emitting slot. The light receiving area of ​​the light receiving slot may be the same size (area) as the light emitting area of ​​the light emitting slot, but may be wider than the light emitting area of ​​the light emitting slot in order to detect light with high sensitivity.

[0061] The address of the light receiving slot includes a horizontal light emission address and a vertical light emission address. For example, when the light receiving surface of the light receiving device 302 is represented by an XY orthogonal coordinate system, the horizontal light receiving address indicates the X coordinate, and the vertical light receiving address indicates the Y coordinate. For example, the horizontal light receiving address ADDRXH1 and the vertical light receiving address ADDRXV1 indicate the start point and width of one light receiving slot. ADDRXH1Start and ADDRXV1Start indicate the X coordinate and the Y coordinate of the start point of the light receiving slot. ADDRXH1Width and ADDRXV1Width indicate the width in the X direction and the width in the Y direction from the start point of the light receiving slot. This specifies the area of ​​the light emitting slot to be operated on the light receiving surface. Similarly, the horizontal light receiving address ADDRXHn and the vertical light receiving address ADDRXVn indicate the area of ​​the nth light receiving slot. That is, in FIG. 7B, the light receiving signal INST_RX specifies n light receiving slots. The light receiving area setting unit 326 sets n light receiving slots designated by the light receiving signal INST_RX to operate. The number of light emission is the number of light emission of the light emitting device 301, and is also the number of light reception of the designated n light receiving slots. Therefore, the light receiving device 302 can determine the end point of the light receiving operation by detecting the same number of reflected lights as the number of light emission. End of Frame indicates the end point of the light receiving signal INST_RX. Note that Start of Frame may be used instead of End of Frame. Start of Frame is data indicating the start point of the light emission signal INST_RX. The boundary of each light emission signal INST_RX can be known by either End of Frame or Start of Frame. Therefore, it is sufficient that either End of Frame or Start of Frame is included in the light emission signal INST_RX. Checksum is data for verifying the accuracy of the light emission signal INST_RX, and may be error code correction. The checksum can verify the correctness of the command of the light receiving signal INST_RX to ensure the safety of the function of the light receiving device 302.

[0062] By using such a light receiving signal INST_RX, the light receiving device 302 sets the light receiving region and the number of times of light receiving.

[0063] 8A to 8C are conceptual diagrams showing the correspondence between light emitting slots and light receiving slots. In Fig. 8A to 8C, the light emitting slots of the light emitting device 301 are indicated by SLTtx. ​​The light receiving slots of the light receiving device 302 are indicated by SLTrx. Each frame in Fig. 8A to 8C indicates a light emitting slot or a light receiving slot.

[0064] The light-emitting area indicated by the light-emitting address of the light-emitting signal INST_TX may be one light-emitting slot SLTtx or multiple light-emitting slots SLTtx. ​​The light-receiving area indicated by the light-receiving address of the light-receiving signal INST_RX may be one light-receiving slot SLTrx or multiple light-receiving slots SLTrx. One or multiple light-receiving slots SLTrx corresponding to one or multiple light-emitting slots SLTtx of the light-emitting area are specified by the light-receiving signal INST_RX.

[0065] The light emitting slot SLTtx may be a single light emitting element (laser diode) or may be composed of multiple light emitting elements. The light receiving slot SLTrx may be a single light receiving element (photodiode) or may be composed of multiple light receiving elements.

[0066] The correspondence relationship between the addresses of the light-emitting slots and the addresses of the light-receiving slots stored in the memory 302e may be a correspondence relationship between one light-emitting slot SLTtx and multiple light-receiving slots SLTrx as shown in Figures 8A to 8C. Conversely, although not shown, the correspondence relationship between the addresses of the light-emitting slots and the addresses of the light-receiving slots stored in the memory 302e may be a correspondence relationship between multiple light-emitting slots SLTtx and one light-receiving slot SLTrx.

[0067] The position of the light receiving slot SLTrx on the light receiving surface approximately corresponds to the position of the light emitting slot SLTtx on the light emitting surface. Also, the area of ​​the light receiving area corresponding to the light emitting area that emits light may be larger than the area of ​​the light emitting area. This allows the light receiving device 302 to detect with high sensitivity the reflected light that is the light from the light emitting device 301 reflected by the target object.

[0068] 8C, the number of light-emitting regions indicated by the light-emitting slot SLTtx may be multiple. In this case, multiple light-receiving regions are set corresponding to the multiple light-emitting regions.

[0069] 6 again, in response to receiving the trigger signal TRG_I of the light emitting device 301 at t2, the light emitting device 301 transmits a trigger signal TRG_O to the light receiving device 302. At t5, the light receiving device 302 receives the trigger signal TRG_O. As a result, the light receiving device 302 starts a light receiving operation.

[0070] At t6, in response to receiving trigger signal TRG_I, light emitting device 301 causes light emitting area 318 to emit light. At this time, the light emitting slot of light emitting area 318 specified by light emitting signal INST_TX emits light the number of times specified by light emitting signal INST_TX.

[0071] 6, the light receiving device 302 ends the light receiving operation by receiving the same number of reflected lights as the number of times it emitted light. As a result, the distance measurement processing unit 328 calculates the distance D using the emission timing obtained from the light emitting device 301 and the reception timing of the reflected light detected in the pixel area 327.

[0072] The distance measuring system 300 repeats the operations from t1 to t6. The light emitting device 301 may set the light emitting slot and the number of times of light emission according to the next light emitting signal INST_TX so as to overlap with the light emitting timing (t6).

[0073] As described above, according to this embodiment, the host 306, the light emitting device 301, and the light receiving device 302 are serially connected (daisy chain connected) by the serial communication lines 304a to 304c and 305a to 305c. Therefore, the light emission signal INST_TX, the trigger signal TRG_I, and the clock signal INCK transmitted from the host 306 are transmitted only to the light emitting device 301. The signals are not directly transmitted from the host 306 to the light receiving device 302. The light emitting device 301 transmits the light emission signal INST_TX, the trigger signal TRG_O, and the clock signal INCK to the light receiving device 302, and the light receiving device 302 obtains these signals. In this way, the host 306, the light emitting device 301, and the light receiving device 302 are daisy chain connected to transmit the light emission signal INST_TX, the trigger signal TRG_I, and the clock signal INCK by serial communication. As a result, the host 306 only needs to transmit the light emission signal INST_TX, the trigger signal TRG_I, and the clock signal INCK to the light emitting device 301, and does not need to transmit any signal to the light receiving device 302. This makes it possible to reduce the number of signal wirings between the host 306 and the light emitting device 301 or the light receiving device 302. For example, in this embodiment, the number of serial communication lines 304a to 304c between the host 306 and the light emitting device 301 or the light receiving device 302 is only two, excluding the wiring for the clock signal INCK. As a result, in this embodiment, the light emitting surface and the light receiving surface are divided into a plurality of slots, and while allowing control for each slot, the number of signal lines is reduced, thereby making it possible to miniaturize the distance measuring system 300 and reduce costs.

[0074] Second embodiment 9 is a block diagram showing a configuration example of a distance measuring system according to the second embodiment. In the second embodiment, the light emitting device 301 includes a light emission signal processing circuit 301f and a memory 301e, and converts the light emission signal INST_TX into a light reception signal INST_RX. In this case, the light receiving device 302 does not need to convert the light emission signal INST_TX into a light reception signal INST_RX, so the memory 302e can be omitted, and a buffer 302f can be provided instead of the light emission signal processing circuit 302c.

[0075] The memory 301e stores the correspondence between the address of the light-emitting slot to be illuminated and the address of the light-receiving slot to be operated correspondingly. The light emission signal processing circuit 301f converts the light emission signal INST_TX into the light reception signal INST_RX using the correspondence between the address of the light-emitting slot stored in the memory 302e and the address of the light reception slot corresponding to the address. The light reception signal INST_RX is transmitted to the light receiving device 302 via the serial communication line 305b.

[0076] 4 sets a light emission trigger according to the number of times the light emitting device 301 emits light, which is included in the light emission signal INST_TX. The light emitting area setting unit 316 of the light emitting device 301 specifies a light emitting area according to the address of the light emitting slot in the light emission signal INST_TX.

[0077] The light receiving device 302 receives the light receiving signal INST_RX and stores it in a buffer 302f. The light receiving timing adjustment unit 325 of the light receiving device 302 in Fig. 5 determines a light receiving period according to the number of times the light emitting device 301 emits light, which is included in the light receiving signal INST_RX. The light receiving area setting unit 326 of the light receiving device 302 specifies a light receiving area according to the address of the light receiving slot of the light receiving signal INST_RX.

[0078] Other configurations and operations of the second embodiment may be similar to those of the first embodiment, and therefore the second embodiment can achieve the same effects as the first embodiment.

[0079] Third embodiment 10 is a block diagram showing an example of the configuration of a distance measuring system according to the third embodiment. In the third embodiment, the connection relationship between the light emitting device 301 and the light receiving device 302 is reversed from that in the first embodiment. That is, the host 306 is serially connected to the light receiving device 302 via serial communication lines 304a to 304c, and the light receiving device 302 is serially connected to the light emitting device 301 via serial communication lines 305a to 305c.

[0080] In the third embodiment, the host 306 transmits a light reception signal INST_RX to the light receiving device 302 via a serial communication line 304b. In addition, the host 306 transmits a trigger signal TRG_I indicating a light reception timing to the light receiving device 302 via a serial communication line 304c.

[0081] The light receiving device 302 includes a buffer 302f, which temporarily holds the light receiving signal INST_RX and transmits it to the light emitting device 301 via a serial communication line 305b. The light receiving timing adjustment unit 325 of the light receiving device 302 in FIG. 5 determines the light receiving period according to the number of times the light emitting device 301 emits light, which is included in the light receiving signal INST_RX. The light receiving area setting unit 326 of the light receiving device 302 designates the light receiving area according to the address of the light receiving slot of the light receiving signal INST_RX. In addition, the trigger processing circuit 302d starts the light receiving operation of the light receiving device 302 upon receiving the trigger signal TRG_I. The light receiving period of the light receiving device 302 is started so as to include the timing at which the light from the light emitting device 301 is received, which is reflected from the target object.

[0082] The light emitting device 301 receives the light receiving signal INST_RX via the serial communication line 305b, and receives the trigger signal TRG_O via the serial communication line 305c. The light emitting device 301 includes a light receiving signal processing circuit 301g and a memory 301e, and converts the light receiving signal INST_RX into a light emitting signal INST_TX. The memory 301e may be the same as that in the first embodiment. The light receiving signal processing circuit 301g converts the light receiving signal INST_RX into a light emitting signal INST_TX. The light emitting signal INST_TX is transmitted to the light emitting device 301 via the serial communication line 305b. The light emission timing adjustment unit 315 of the light emitting device 301 in FIG. 4 sets a light emission trigger according to the number of times the light emitting device 301 emits light, which is included in the light emission signal INST_TX. The light emission area setting unit 316 of the light emitting device 301 specifies a light emission area according to the address of the light emission slot of the light emission signal INST_TX. In addition, the trigger processing circuit 301d starts the light emitting operation of the light emitting device 301 upon receiving the trigger signal TRG_O.

[0083] Other configurations and operations of the third embodiment may be similar to those of the first embodiment, and therefore the third embodiment can achieve the same effects as the first embodiment.

[0084] (Fourth embodiment) 11 is a block diagram showing a configuration example of a distance measuring system according to the fourth embodiment. In the fourth embodiment, the light receiving device 302 includes a light receiving signal processing circuit 302g and a memory 302e, and converts the light receiving signal INST_RX into a light emitting signal INST_TX. In this case, since the light emitting device 301 does not need to convert the light receiving signal INST_RX into a light emitting signal INST_TX, the memory 301e can be omitted, and a buffer 301c may be provided instead of the light emitting signal processing circuit 301f.

[0085] The memory 302e may be the same as that in the first embodiment. The light reception signal processing circuit 302g converts the light reception signal INST_RX into a light emission signal INST_TX. The light emission signal INST_TX is transmitted to the light emitting device 301 via a serial communication line 305b.

[0086] 5 sets a light receiving trigger according to the number of times the light emitting device 301 emits light, which is included in the light receiving signal INST_RX. The light receiving region setting section 326 of the light receiving device 302 specifies a light receiving region according to the address of the light receiving slot in the light receiving signal INST_RX.

[0087] The light emitting device 301 receives the light emitting signal INST_TX and stores it in a buffer 301c. The light emitting timing adjustment unit 315 of the light emitting device 301 in Fig. 5 determines the light emitting period according to the number of times the light emitting device 301 emits light, which is included in the light emitting signal INST_TX. The light emitting area setting unit 316 of the light emitting device 301 specifies the light emitting area according to the address of the light emitting slot of the light emitting signal INST_TX.

[0088] Other configurations and operations of the fourth embodiment may be similar to those of the third embodiment, and therefore the fourth embodiment can achieve the same effects as the third embodiment.

[0089] Fifth embodiment FIG. 12 is a block diagram showing a configuration example of a distance measuring system according to the fifth embodiment. In the fifth embodiment, the light emitting device 301 and the light receiving device 302 are connected in parallel to the host 306 via serial communication lines 304a and 305a. Therefore, both the light emitting device 301 and the light receiving device 302 receive a clock signal INCK from the host 306. The light emitting device 301 is connected to the host 306 via a serial communication line 304b. The light receiving device 302 is connected to the host 306 via a serial communication line 305b. Therefore, the light emitting device 301 and the light receiving device 302 individually receive a light emission signal INST_TX and a light reception signal INST_RX from the host 306. The light emitting device 301 and the light receiving device 302 each include a buffer 301c and 302f, but the light emission signal processing circuits 301f and 302c and the memories 301e and 302e may be omitted.

[0090] Meanwhile, the host 306, the light emitting device 301, and the light receiving device 302 are connected in series via serial communication lines 304c and 305c. That is, the host 306 is connected to the light emitting device 301 via the serial communication line 304c, and the light emitting device 301 is connected to the light receiving device 302 via the serial communication line 305c. Therefore, the host 306 transmits a trigger signal TRG_I to the light emitting device 301 via the serial communication line 304c. The light emitting device 301 transfers the trigger signal TRG_I to the light receiving device 302 as a trigger signal TRG_O via the serial communication line 305c.

[0091] In this way, the clock signal INCK, the light emission signal INST_TX, and the light reception signal INST_RX other than the trigger signals TRG_I and TRG_O are directly transmitted from the host 306 to the light emitting device 301 or the light receiving device 302. For the trigger signals TRG_I and TRG_O, the host 306, the light emitting device 301, and the light receiving device 302 are daisy-chain connected. In this case, the timing jitter between the light emission timing of the light emitting device 301 and the light reception timing of the light receiving device 302 can be reduced compared to the case where both the light emitting device 301 and the light receiving device 302 receive trigger signals from the host 306 in parallel.

[0092] Other configurations and operations of the fifth embodiment may be the same as those of the first embodiment, and therefore the fifth embodiment can achieve the same effects as the first embodiment.

[0093] Since the light emission signal INST_TX and the light reception signal INST_RX are transmitted from the host 306, the number of serial communication lines connected to the host 306 increases. However, the number of serial communication lines 304a for transmitting the clock signal INCK connected to the host 306 and the number of serial communication lines 304c for transmitting the trigger signal TRG_I are the same as in the first embodiment. Therefore, even in the fifth embodiment, the effect of reducing the number of signal lines and connectors connected to the host 306 can be obtained.

[0094] Sixth embodiment FIG. 13 is a block diagram showing an example of the configuration of a distance measuring system according to the sixth embodiment. In the sixth embodiment, the host 306, the light emitting device 301, and the light receiving device 302 are connected in series via serial communication lines 304c and 305c, which is the same as the fifth embodiment. However, the host 306 is connected to the light receiving device 302 via the serial communication line 304c, and the light receiving device 302 is connected to the light emitting device 301 via the serial communication line 305c. That is, the connection relationship between the light emitting device 301 and the light receiving device 302 with respect to the host 306 is reversed. Therefore, the host 306 transmits a trigger signal TRG_I to the light receiving device 302 via the serial communication line 304c. The light receiving device 302 transfers the trigger signal TRG_I to the light emitting device 301 as a trigger signal TRG_O via the serial communication line 305c.

[0095] In the sixth embodiment, since the host 306, the light emitting device 301, and the light receiving device 302 are daisy-chain connected with respect to the trigger signals TRG_I and TRG_O, the same effects as those of the fifth embodiment can be obtained.

[0096] Seventh embodiment 14 is a block diagram showing an example of the configuration of a distance measuring system according to the seventh embodiment. In the seventh embodiment, a plurality of light emitting devices 301 are connected in series in a daisy chain from a host 306 via a plurality of serial communication lines 304a to 304c, and further, a plurality of light receiving devices 302 are connected in series in a daisy chain via a plurality of serial communication lines 305a to 305c. The last stage light emitting device 301 among the plurality of light emitting devices 301 and the first stage light receiving device 302 among the plurality of light receiving devices 302 are connected via the serial communication lines 305a to 305c.

[0097] The configuration of the plurality of light emitting devices 301 may be the same as that of the first embodiment.

[0098] Each light receiving device 302 includes both a buffer 302f and an emission signal processing circuit 302c. The buffer 302f of each light receiving device 302 holds the received emission signal INST_TX and transmits the emission signal INST_TX to the next stage light receiving device 302. The emission signal processing circuit 302c of each light receiving device 302 converts the received emission signal INST_TX into a received light signal INST_RX. Other configurations and operations of each light receiving device 302 may be the same as those of the light receiving device 302 of the first embodiment.

[0099] In this way, a plurality of light emitting devices 301 and a plurality of light receiving elements may be daisy-chained via serial communication lines to one host 306. Other configurations and operations of the seventh embodiment may be the same as those of the first embodiment.

[0100] Incidentally, the seventh embodiment can be easily applied to any of the second to fourth embodiments, and therefore the seventh embodiment can obtain the effects of any of the second to fourth embodiments.

[0101] (Example of application to moving objects) The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of moving body such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility device, an airplane, a drone, a ship, a robot, etc.

[0102] FIG. 15 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a moving object control system to which the technology according to the present disclosure can be applied.

[0103] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in Fig. 15, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside-vehicle information detection unit 12030, an inside-vehicle information detection unit 12040, and an integrated control unit 12050. Also, as functional configurations of the integrated control unit 12050, a microcomputer 12051, an audio / video output unit 12052, and an in-vehicle network I / F (Interface) 12053 are illustrated.

[0104] The drivetrain control unit 12010 controls the operation of devices related to the drivetrain of the vehicle in accordance with various programs. For example, the drivetrain control unit 12010 functions as a control device for a drive force generating device for generating a drive force of the vehicle, such as an internal combustion engine or a drive motor, a drive force transmission mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating a braking force of the vehicle.

[0105] The body system control unit 12020 controls the operation of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as head lamps, back lamps, brake lamps, turn signals, and fog lamps. In this case, radio waves or signals of various switches transmitted from a portable device that replaces a key may be input to the body system control unit 12020. The body system control unit 12020 receives the input of these radio waves or signals and controls the door lock device, power window device, lamps, and the like of the vehicle.

[0106] The outside-vehicle information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 12031 is connected to the outside-vehicle information detection unit 12030. The outside-vehicle information detection unit 12030 causes the imaging unit 12031 to capture an image outside the vehicle and receives the captured image. The outside-vehicle information detection unit 12030 may perform object detection processing or distance detection processing for a person, a car, an obstacle, a sign, or characters on a road surface, based on the received image.

[0107] The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal according to the amount of light received. The imaging unit 12031 can output the electrical signal as an image, or as distance measurement information. The light received by the imaging unit 12031 may be visible light or invisible light such as infrared light.

[0108] The in-vehicle information detection unit 12040 detects information inside the vehicle. For example, a driver state detection unit 12041 that detects the state of the driver is connected to the in-vehicle information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that captures an image of the driver, and the in-vehicle information detection unit 12040 may calculate the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 12041, or may determine whether the driver is dozing.

[0109] The microcomputer 12051 can calculate control target values ​​for the driving force generating device, the steering mechanism, or the braking device based on the information inside and outside the vehicle acquired by the outside-of-vehicle information detection unit 12030 or the inside-vehicle information detection unit 12040, and output a control command to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of an ADAS (Advanced Driver Assistance System), including vehicle collision avoidance or impact mitigation, following driving based on the inter-vehicle distance, vehicle speed maintenance driving, vehicle collision warning, vehicle lane departure warning, etc.

[0110] In addition, the microcomputer 12051 can perform cooperative control for the purpose of autonomous driving, which allows the vehicle to travel autonomously without relying on the driver's operation, by controlling the driving force generating device, steering mechanism, braking device, etc. based on information about the surroundings of the vehicle acquired by the outside vehicle information detection unit 12030 or the inside vehicle information detection unit 12040.

[0111] Furthermore, the microcomputer 12051 can output a control command to the body system control unit 12030 based on the information outside the vehicle acquired by the outside-vehicle information detection unit 12030. For example, the microcomputer 12051 can control the headlamps according to the position of a preceding vehicle or an oncoming vehicle detected by the outside-vehicle information detection unit 12030, and perform cooperative control for the purpose of preventing glare, such as switching from high beams to low beams.

[0112] The audio / video output unit 12052 transmits at least one output signal of audio and video to an output device capable of visually or audibly notifying information to passengers in the vehicle or the outside of the vehicle. In the example of Fig. 15, an audio speaker 12061, a display unit 12062, and an instrument panel 12063 are exemplified as the output device. The display unit 12062 may include at least one of an on-board display and a head-up display, for example.

[0113] FIG. 16 is a diagram showing an example of the installation position of the imaging unit 12031.

[0114] In FIG. 16, the imaging unit 12031 includes imaging units 12101, 12102, 12103, 12104, and 12105.

[0115] The imaging units 12101, 12102, 12103, 12104, and 12105 are provided at positions such as the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield in the vehicle interior of the vehicle 12100. The imaging unit 12101 provided at the front nose and the imaging unit 12105 provided at the upper part of the windshield in the vehicle interior mainly acquire images of the front of the vehicle 12100. The imaging units 12102 and 12103 provided at the side mirrors mainly acquire images of the sides of the vehicle 12100. The imaging unit 12104 provided at the rear bumper or back door mainly acquires images of the rear of the vehicle 12100. The imaging unit 12105 provided at the upper part of the windshield in the vehicle interior is mainly used to detect a preceding vehicle, a pedestrian, an obstacle, a traffic light, a traffic sign, a lane, or the like.

[0116] 16 shows an example of the imaging ranges of the imaging units 12101 to 12104. An imaging range 12111 indicates the imaging range of the imaging unit 12101 provided on the front nose, imaging ranges 12112 and 12113 indicate the imaging ranges of the imaging units 12102 and 12103 provided on the side mirrors, respectively, and an imaging range 12114 indicates the imaging range of the imaging unit 12104 provided on the rear bumper or back door. For example, an overhead image of the vehicle 12100 viewed from above is obtained by superimposing the image data captured by the imaging units 12101 to 12104.

[0117] At least one of the imaging units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera made up of a plurality of imaging elements, or may be an imaging element having pixels for detecting a phase difference.

[0118] For example, the microcomputer 12051 can extract, as a preceding vehicle, a three-dimensional object that is the closest three-dimensional object on the travel path of the vehicle 12100 and travels at a predetermined speed (for example, 0 km / h or more) in approximately the same direction as the vehicle 12100, by calculating the distance to each three-dimensional object in the imaging ranges 12111 to 12114 and the change over time of this distance (relative speed with respect to the vehicle 12100) based on the distance information obtained from the imaging units 12101 to 12104. Furthermore, the microcomputer 12051 can set a vehicle distance to be secured in advance in front of the preceding vehicle, and perform automatic brake control (including follow-up stop control) and automatic acceleration control (including follow-up start control). In this way, cooperative control can be performed for the purpose of automatic driving that travels autonomously without relying on the driver's operation.

[0119] For example, the microcomputer 12051 classifies and extracts three-dimensional object data on three-dimensional objects into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects based on distance information obtained from the imaging units 12101 to 12104, and can use the data for automatic obstacle avoidance. For example, the microcomputer 12051 distinguishes obstacles around the vehicle 12100 into obstacles that are visible to the driver of the vehicle 12100 and obstacles that are difficult to see. Then, the microcomputer 12051 determines a collision risk indicating the risk of collision with each obstacle, and when the collision risk is equal to or greater than a set value and a collision is possible, the microcomputer 12051 can provide driving assistance for collision avoidance by outputting an alarm to the driver via the audio speaker 12061 or the display unit 12062, or by performing forced deceleration or avoidance steering via the drive system control unit 12010.

[0120] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether or not a pedestrian is present in the captured images of the imaging units 12101 to 12104. The recognition of such a pedestrian is performed, for example, by a procedure of extracting feature points in the captured images of the imaging units 12101 to 12104 as infrared cameras, and a procedure of performing pattern matching processing on a series of feature points that indicate the contour of an object to determine whether or not the object is a pedestrian. When the microcomputer 12051 determines that a pedestrian is present in the captured images of the imaging units 12101 to 12104 and recognizes the pedestrian, the audio / image output unit 12052 controls the display unit 12062 to superimpose a rectangular contour line for emphasis on the recognized pedestrian. The audio / image output unit 12052 may also control the display unit 12062 to display an icon or the like indicating a pedestrian at a desired position.

[0121] The above describes an example of a vehicle control system to which the technology according to the present disclosure can be applied. The technology according to the present disclosure can be applied to, for example, the distance measurement system of the imaging unit 12031 in the configuration described above.

[0122] The present technology can be configured as follows.

[0123] (1) A light-emitting part that emits light; a light receiving unit that receives light reflected by an object from the light emitting unit; a control calculation unit that controls the light emitting unit or the light receiving unit and calculates a distance to the target object based on a time from a light emission timing of the light emitting unit to a light receiving timing of the light receiving unit; a first signal line that transmits a light emission signal instructing a light emission region of the light emitting unit from the control and calculation unit or the light receiving unit to the light emitting unit by serial communication; a second signal line that transmits a first trigger signal indicating a light emission timing from the control and calculation unit or the light receiving unit to the light emitting unit by serial communication; a third signal line that transmits a light receiving signal indicating a light receiving region in the light receiving unit from the control and calculation unit or the light emitting unit to the light receiving unit by serial communication; A distance measuring system comprising: a fourth signal line that transmits a second trigger signal indicating a light receiving timing from the control and calculation unit or the light emitting unit to the light receiving unit via serial communication.

[0124] (2) the control and calculation unit is serially connected to the light-emitting unit via the first and second signal lines, The distance measuring system according to (1), wherein the light emitting unit is serially connected to the light receiving unit via the third and fourth signal lines.

[0125] (3) the control and calculation unit transmits the light emission signal to the light emission unit via the first signal line; the light emitting unit receives the light emitting signal and transmits the light emitting signal to the light receiving unit via the third signal line; The distance measuring system according to (1) or (2), wherein the light receiving unit receives the light emission signal from the light emitting unit and converts the light emission signal into the light receiving signal.

[0126] (4) the control and calculation unit transmits the light emission signal to the light emission unit via the first signal line; the light emitting unit receives the light emitting signal, converts the light emitting signal into the light receiving signal, and transmits the light emitting signal to the light receiving unit via the third signal line; The distance measuring system according to (1) or (2), wherein the light receiving unit receives the light receiving signal.

[0127] (5) the control and calculation unit transmits the first trigger signal to the light-emitting unit via the second signal line; the light-emitting unit receives the first trigger signal and transmits the first trigger signal as the second trigger signal to the light-receiving unit via the fourth signal line; The distance measuring system according to any one of (1) to (4), wherein the light receiving unit receives the second trigger signal. (6) the control and calculation unit is serially connected to the light receiving unit via the third and fourth signal lines, The distance measuring system according to (1), wherein the light receiving unit is serially connected to the light emitting unit via the first and second signal lines.

[0128] (7) the control and calculation unit transmits the light receiving signal to the light receiving unit via the third signal line; the light receiving unit receives the light receiving signal and transmits the light receiving signal to the light emitting unit via the first signal line; The distance measuring system according to (1) or (6), wherein the light emitting unit receives the received light signal and converts the received light signal into the light emitting signal.

[0129] (8) the control and calculation unit transmits the light receiving signal to the light receiving unit via the third signal line; the light receiving unit converts the light receiving signal into the light emitting signal and transmits the light receiving signal to the light emitting unit via the first signal line; The distance measurement system according to (1) or (6), wherein the light emitting unit receives the light emitting signal.

[0130] (9) the control and calculation unit transmits the second trigger signal to the light receiving unit via the fourth signal line; the light receiving unit receives the second trigger signal and transmits the second trigger signal as the first trigger signal to the light emitting unit via the second signal line; The distance measuring system according to any one of (1), (6) to (8), wherein the light emitting unit receives the first trigger signal. (10) the control and calculation unit is serially connected to the light-emitting unit and the light-receiving unit via the first and third signal lines, respectively, and is serially connected to the light-emitting unit via the second signal line; The distance measuring system according to (1), wherein the light receiving unit is serially connected to the light emitting unit via the fourth signal line.

[0131] (11) the control and calculation unit transmits the light emission signal to the light emission unit via the first signal line, transmits the light reception signal to the light reception unit via the third signal line, and transmits the first trigger signal to the light emission unit via the second signal line; the light-emitting unit receives the first trigger signal and transmits the first trigger signal to the light-receiving unit as the second trigger signal; The distance measuring system according to (10), wherein the light receiving unit receives the second trigger signal.

[0132] (12) the control and calculation unit transmits the light emission signal to the light emission unit via the first signal line, transmits the light reception signal to the light reception unit via the third signal line, and transmits the second trigger signal to the light reception unit via the fourth signal line; the light receiving unit receives the second trigger signal and transmits the second trigger signal to the light emitting unit as the first trigger signal; The distance measurement system according to (10), wherein the light emitting unit receives the first trigger signal.

[0133] (13) the light-emitting section and the light-receiving section are each divided into a plurality of the light-emitting regions and a plurality of the light-receiving regions, The distance measuring system according to any one of (1) to (12), wherein the control and calculation unit controls the light emitting unit for each of the light emitting regions and controls the light receiving unit for each of the light receiving regions.

[0134] (14) a fifth signal line that transmits a clock signal from the control and calculation unit or the light receiving unit to the light emitting unit by serial communication; The distance measuring system according to any one of (1) to (13), further comprising a sixth signal line that transmits a clock signal from the control and calculation unit or the light emitting unit to the light receiving unit by serial communication.

[0135] (15) A plurality of the light emitting units are connected in series to be capable of serial communication, The distance measuring system according to any one of (1) to (14), wherein the plurality of light receiving units are connected in series to enable serial communication.

[0136] (16) A light-emitting part that emits light; a first interface that receives a light emission signal indicating a light emission region of the light emitting unit from the control and calculation unit or the light receiving unit by serial communication; a first buffer for holding the light emission signal; a second interface that transmits the light emission signal or a light reception signal obtained by converting the light emission signal to a light reception device by serial communication.

[0137] (17) a light receiving unit that receives light reflected by an object from the light emitting unit; a third interface that receives a light receiving signal indicating a light receiving region in the light receiving unit from the control and calculation unit or the light emitting unit by serial communication; a second buffer for holding the received light signal; and a fourth interface that transmits the received light signal or a light emitting signal obtained by converting the received light signal to the light emitting device via serial communication.

[0138] The present disclosure is not limited to the above-described embodiment, and various modifications are possible without departing from the scope of the present disclosure. Furthermore, the effects described in this specification are merely examples and are not limiting, and other effects may be obtained. [Explanation of symbols]

[0139] 300 Distance Measuring System 301 Light emitting device 302 Light receiving device 304a~304c, 305a~305c Serial communication line 306 Host 301a,302a Multiplier 301b, 301c, 302b, 302c Buffer 301d Trigger processing circuit 302e Memory IFtx_I, IFtx_O Interface 315 Light emission timing adjustment unit 316 Light emitting area setting section 317 Driver 318 Luminous Area 325 Light receiving timing adjustment unit 326 Light receiving area setting unit 327 pixel area 328 Distance measurement processing section

Claims

1. A light-emitting part that emits light; a light receiving unit that receives light reflected by an object from the light emitting unit; a control calculation unit that controls the light emitting unit or the light receiving unit and calculates a distance to the target object based on a time from a light emission timing of the light emitting unit to a light receiving timing of the light receiving unit; a first signal line that transmits a light emission signal indicating a light emission region of the light emitting unit from the control and calculation unit or the light receiving unit to the light emitting unit by serial communication; a second signal line for transmitting a first trigger signal indicating a light emission timing from the control and calculation unit or the light receiving unit to the light emitting unit by serial communication; a third signal line that transmits a light receiving signal indicating a light receiving region in the light receiving unit from the control and calculation unit or the light emitting unit to the light receiving unit by serial communication; A distance measuring system comprising: a fourth signal line that transmits a second trigger signal indicating a light receiving timing from the control and calculation unit or the light emitting unit to the light receiving unit via serial communication.

2. the control and calculation unit is serially connected to the light emitting unit via the first and second signal lines, The distance measuring system according to claim 1 , wherein the light emitting unit is serially connected to the light receiving unit via the third and fourth signal lines.

3. the control and calculation unit transmits the light emission signal to the light emission unit via the first signal line; the light emitting unit receives the light emitting signal and transmits the light emitting signal to the light receiving unit via the third signal line; The distance measuring system according to claim 1 , wherein the light receiving unit receives the light emission signal from the light emitting unit and converts the light emission signal into the light receiving signal.

4. the control and calculation unit transmits the light emission signal to the light emission unit via the first signal line; the light emitting unit receives the light emitting signal, converts the light emitting signal into the light receiving signal, and transmits the light emitting signal to the light receiving unit via the third signal line; The distance measuring system according to claim 1 , wherein the light receiving unit receives the light receiving signal.

5. the control and calculation unit transmits the first trigger signal to the light-emitting unit via the second signal line; the light-emitting unit receives the first trigger signal and transmits the first trigger signal as the second trigger signal to the light-receiving unit via the fourth signal line; The distance measuring system according to claim 1 , wherein the light receiving unit receives the second trigger signal.

6. the control and calculation unit is serially connected to the light receiving unit via the third and fourth signal lines, The distance measuring system according to claim 1 , wherein the light receiving section is serially connected to the light emitting section via the first and second signal lines.

7. the control and calculation unit transmits the light receiving signal to the light receiving unit via the third signal line; the light receiving unit receives the light receiving signal and transmits the light receiving signal to the light emitting unit via the first signal line; The distance measuring system according to claim 1 , wherein the light emitting unit receives the light reception signal and converts the light reception signal into the light emission signal.

8. the control and calculation unit transmits the light receiving signal to the light receiving unit via the third signal line; the light receiving unit converts the light receiving signal into the light emitting signal and transmits the light receiving signal to the light emitting unit via the first signal line; The distance measuring system according to claim 1 , wherein the light emitting unit receives the light emitting signal.

9. the control and calculation unit transmits the second trigger signal to the light receiving unit via the fourth signal line; the light receiving unit receives the second trigger signal and transmits the second trigger signal as the first trigger signal to the light emitting unit via the second signal line; The distance measuring system according to claim 1 , wherein the light emitting unit receives the first trigger signal.

10. the control and calculation unit is serially connected to the light-emitting unit and the light-receiving unit via the first and third signal lines, respectively, and is serially connected to the light-emitting unit via the second signal line; The distance measuring system according to claim 1 , wherein the light receiving unit is serially connected to the light emitting unit via the fourth signal line.

11. the control and calculation unit transmits the light emission signal to the light emission unit via the first signal line, transmits the light reception signal to the light reception unit via the third signal line, and transmits the first trigger signal to the light emission unit via the second signal line; the light-emitting unit receives the first trigger signal and transmits the first trigger signal to the light-receiving unit as the second trigger signal; The distance measuring system according to claim 10 , wherein the light receiving unit receives the second trigger signal.

12. the control and calculation unit transmits the light emission signal to the light emission unit via the first signal line, transmits the light reception signal to the light reception unit via the third signal line, and transmits the second trigger signal to the light reception unit via the fourth signal line; the light receiving unit receives the second trigger signal and transmits the second trigger signal to the light emitting unit as the first trigger signal; The distance measuring system according to claim 10 , wherein the light emitting unit receives the first trigger signal.

13. the light-emitting section and the light-receiving section are each divided into a plurality of the light-emitting regions and a plurality of the light-receiving regions, The distance measuring system according to claim 1 , wherein the control and calculation unit controls the light emitting unit for each of the light emitting regions and controls the light receiving unit for each of the light receiving regions.

14. a fifth signal line that transmits a clock signal from the control and calculation unit or the light receiving unit to the light emitting unit by serial communication; The distance measuring system according to claim 1 , further comprising: a sixth signal line for transmitting a clock signal from the control and calculation unit or the light emitting unit to the light receiving unit by serial communication.

15. A plurality of the light emitting units are connected in series to be capable of serial communication, The distance measuring system according to claim 1 , wherein the light receiving units are connected in series to enable serial communication.

16. A light-emitting part that emits light; a first interface that receives a light emission signal indicating a light emission region of the light emitting unit from a control calculation unit or a light receiving unit by serial communication; a first buffer for holding the light emission signal; a second interface that transmits the light emission signal or a light reception signal obtained by converting the light emission signal to a light reception device by serial communication.

17. a light receiving unit that receives light reflected by an object from the light emitting unit; a third interface that receives a light receiving signal indicating a light receiving region in the light receiving unit from the control and calculation unit or the light emitting unit by serial communication; a second buffer for holding the received light signal; a fourth interface that transmits the received light signal or a light emitting signal obtained by converting the received light signal to the light emitting device via serial communication.

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