Light-emitting device and distance measuring device

Abstract

[Problem] To be able to expand a range in which distance can be measured. [Solution] This light-emitting device comprises: a light-emitting unit for emitting band-shaped light which extends in a first direction while scanning in a second direction intersecting the first direction; and an optical element for diffusing the emitted band-shaped light in the first direction. The light-emitting unit spreads the band-shaped light in the second direction such that reflected light, which is obtained when at least some light included in the band-shaped light diffused by the optical element is reflected by an object, is received in a range which is wider than the minimum light-receiving range of a light-receiving device which receives the reflected light.

Description

Light emitting device and distance measuring device

[0008] ,

[0001] The present disclosure relates to a light emitting device and a distance measuring device.

[0002] There is known a distance measuring device that measures the distance to an object by irradiating the object with light and receiving the reflected light from the object. Such a distance measuring device is called LiDAR (Light Detection and Ranging). LiDAR has a Solid-State method in which the irradiation range of light is scanned while the light projection device is fixed. The Solid-State method is known to be capable of miniaturization and having high durability compared to the mechanical method in which a scanning member such as a polygon mirror is mechanically rotated to scan the irradiation range of light.

[0003] For example, there has been proposed a distance measuring device that efficiently receives light by reading a detection signal from a light receiving element at a position corresponding to the scanning position of the light emitting unit among a plurality of light receiving elements in the light receiving unit (see Patent Document 1).

[0004] International Publication No. 2021 / 161858

[0005] In order for the light receiving unit to efficiently receive the light emitted by the light emitting unit, it is desirable to match the optical characteristics of the light emitting unit and the light receiving unit. For example, a diffuser may be used in the distance measuring device. The diffuser diffuses the light emitted by the light emitting unit and can match the FOV (Field of view) between the light emitting unit and the light receiving unit.

[0006] However, when light is diffused using a diffuser, distortion may occur at the end of the FOV. Due to the distortion, a deviation occurs between the position where the reflected light is irradiated on the light receiving unit and the position of the light receiving element from which the detection signal is read, resulting in a range where distance measurement is impossible. Therefore, the measurable range of the distance measuring device becomes narrow.

[0007] Therefore, the present disclosure provides a light emitting device and a distance measuring device capable of expanding the measurable range.

[0008] To solve the above problems, the present disclosure provides a light-emitting device comprising: a light-emitting unit that emits light while scanning a band of light extending in a first direction in a second direction intersecting the first direction; and an optical element that diffuses the emitted band of light in the first direction, wherein the light-emitting unit spreads the band of light in the second direction such that at least a portion of the light contained in the band of light diffused by the optical element is received over a wider area than the minimum receiving range of a light-receiving device that receives reflected light reflected from an object.

[0009] The light-emitting unit may spread the band of light in the second direction so that the reflected light is received over a range at least twice the minimum light-receiving range of the light-receiving device.

[0010] The light-emitting unit may have a plurality of light-emitting elements arranged in the first direction that emit light simultaneously to generate the band-shaped light.

[0011] The plurality of light-emitting elements are arranged in multiples in the first direction and in the second direction, and the light-emitting unit may generate the band-shaped light by simultaneously emitting light from two or more adjacent light-emitting elements in the second direction and the plurality of light-emitting elements arranged in the first direction.

[0012] The light-emitting unit may control the light-emitting power of each of the light-emitting elements according to the number of light-emitting elements that are emitted simultaneously.

[0013] The light-emitting unit may lower the light-emitting power of each individual light-emitting element as the number of light-emitting elements in the second direction included in the band of light increases.

[0014] The optical system includes an optical system for adjusting the focus of the band-shaped light emitted from the light-emitting unit, and the optical element may diffuse the band-shaped light, which has been focused by the optical system, in a first direction.

[0015] The optical system may blur the band of light emitted from the light-emitting unit in the second direction.

[0016] The optical system may have a greater amount of blur at both ends of the band of light emitted from the light-emitting unit in the first direction than the amount of blur at the center in the first direction.

[0017] Furthermore, the present disclosure provides a distance measuring device comprising: a light-emitting unit that emits light while scanning a band of light extending in a first direction in a second direction intersecting the first direction; an optical element that diffuses the emitted band of light in the first direction; and a light-receiving unit that receives reflected light in which at least a portion of the light contained in the band of light diffused by the optical element is reflected by an object, wherein the light-emitting unit spreads the band of light in the second direction so that the reflected light is received over a wider area than the minimum light-receiving range of the light-receiving unit that receives reflected light in which at least a portion of the light contained in the band of light diffused by the optical element is reflected by an object.

[0018] The light-receiving unit may have a plurality of light-receiving elements arranged in the first direction and receiving the reflected light in the minimum light-receiving range.

[0019] The light-receiving unit includes a plurality of light-receiving elements arranged in the first direction, and has a plurality of light-receiving element groups that receive the reflected light at a plurality of light-receiving timings. The light-emitting unit includes a plurality of light-emitting elements arranged in the first direction and simultaneously emitting light to generate the band-shaped light, and has a plurality of light-emitting element groups that emit the band-shaped light at a plurality of light-emitting timings corresponding to the plurality of light-receiving timings. At least for some of the plurality of light-emitting timings, more light-emitting element groups may emit light than the light-receiving element groups that receive the reflected light at the corresponding light-receiving timings.

[0020] The aforementioned plurality of light emission timings may include multiple types of light emission timings in which the number of light-emitting element groups differs from one another.

[0021] A block diagram showing an example configuration of a distance measuring device equipped with a light-emitting device according to this disclosure. A block diagram showing a detailed configuration of the light-emitting unit. A block diagram showing a detailed configuration of the light-receiving unit. A first diagram illustrating the distance measuring method of the distance measuring device of Figure 1. A second diagram illustrating the distance measuring method of the distance measuring device of Figure 1. A first diagram illustrating a distance measuring method using a diffuser. A second diagram illustrating a distance measuring method using a diffuser. A diagram illustrating the challenges in distance measuring using a diffuser. A first diagram showing the distance measuring method of the distance measuring device according to the first embodiment of this disclosure. A second diagram showing the distance measuring method of the distance measuring device according to the first embodiment of this disclosure. A first diagram showing the distance measuring method of the distance measuring device according to the second embodiment of this disclosure. A second diagram showing the distance measuring method of the distance measuring device according to the second embodiment of this disclosure. A diagram illustrating the operation of the light-emitting unit and light-receiving unit according to the second embodiment of this disclosure. A diagram illustrating the distance measuring method of the distance measuring device according to the third embodiment of this disclosure. A diagram illustrating the operation of the light-emitting unit and light-receiving unit according to the fourth embodiment of this disclosure. A diagram illustrating the distance measuring method of the distance measuring device according to the sixth embodiment of this disclosure. A block diagram showing an example of the general configuration of a vehicle control system. An explanatory diagram showing an example of the installation location of the external information detection unit and the imaging unit.

[0022] The embodiments of the light-emitting device and the distance-measuring device will be described below with reference to the drawings. The following description will focus on the main components of the light-emitting device and the distance-measuring device, but there may be components and functions not shown or described. The following description does not exclude any components or functions not shown or described.

[0023] (First Embodiment) Figure 1 is a block diagram showing an example configuration of a distance measuring device 1 equipped with a light-emitting device 10 according to the present disclosure. The distance measuring device 1 in Figure 1 is, for example, a ToF sensor. The distance measuring device 1 can measure the distance to an object 2 based on emitted light L1 and reflected light L2 obtained by reflecting the emitted light L1 off the object 2. The distance measuring device 1 can be, for example, made of one or more semiconductor substrates. The distance measuring device 1 may be made of a flat semiconductor substrate, or it may be made of a multilayer semiconductor structure in which a plurality of semiconductor substrates are stacked.

[0024] The distance measuring device 1 comprises a control unit 11, a light-emitting unit 12, a light-emitting lens (optical system) 13, a diffuser (optical element) 14, a light-receiving lens 21, a light-receiving unit 22, a calculation unit (distance measuring unit) 23, and an external interface (I / F) 24. In this specification, the light-emitting unit 12, the light-emitting lens 13, and the diffuser 14 are also referred to as the light-emitting device 10. The light-receiving lens 21, the light-receiving unit 22, and the calculation unit 23 are also referred to as the light-receiving device 20.

[0025] The control unit 11 includes, for example, an information processing unit such as a CPU (Central Processing Unit). The control unit 11 controls the light-emitting unit 12 and the light-receiving unit 22, etc. For example, the control unit 11 generates a clock signal to synchronize the light-emitting unit 12 and the light-receiving unit 22.

[0026] The light-emitting unit 12 has a plurality of light-emitting elements, each emitting an emitted light L1. The emitted light L1 is, for example, a band of light extending in one direction. The projection lens 13 adjusts the focus of the emitted light L1 and irradiates it toward the object to be measured 2. The diffuser 14 diffuses the emitted light L1, which has been focused by the projection lens 13, in one direction. In the first embodiment, an example is described in which the diffuser 14 diffuses the emitted light L1, which is a band of light in the horizontal direction, in the horizontal direction.

[0027] The light-receiving lens 21 guides the reflected light L2, which is at least a portion of the light contained in the emitted light L1 reflected by the object to be measured 2, to the light-receiving unit 22. The light-receiving unit 22 has a plurality of light-receiving elements, each of which receives the reflected light L2. The light-receiving unit 22 also has a plurality of pixels (or macro pixels), each containing one or more light-receiving elements. The light-receiving unit 22 outputs a detection signal based on the received reflected light L2. The detection signal includes, for example, information on the number of times the reflected light L2 was detected for each pixel (hereinafter also referred to as the detection count).

[0028] The calculation unit 23 performs distance measurement based on the detection signal. Specifically, the calculation unit 23, for example, aggregates the number of detections output from the light receiving unit 22 for each of several pixels, and creates a histogram based on the pixel values ​​obtained from this aggregation, with the horizontal axis representing flight time and the vertical axis representing the cumulative pixel value. For example, the calculation unit 23 aggregates the number of detections at a predetermined sampling frequency for each emission of light from the light-emitting unit 12 and obtains the pixel value, and repeats this process for multiple emissiones of light from the light-emitting unit 12, thereby creating a histogram with the horizontal axis (histogram bins) representing the sampling period corresponding to flight time and the vertical axis representing the cumulative pixel value obtained by accumulating the pixel values ​​obtained at each sampling period. Furthermore, the calculation unit 23 applies a predetermined filtering process to the created histogram and then identifies the flight time at which the cumulative pixel value peaks from the filtered histogram. Then, based on the identified flight time, the calculation unit 23 calculates the distance from the distance measuring device 1 or the device on which it is mounted to the distance measuring target object 2 that is within the distance measuring range. The distance information calculated by the calculation unit 23 may be output to the host 3, for example, via the external interface 24.

[0029] The external interface 24 transmits information such as the measured distance to a host 3 or other device outside the distance measuring device 1 to a downstream device. The external interface 24 may also receive instructions from the host 3 and cause the distance measuring device 1 to perform distance measurement. The external interface 24 may be a communication adapter for establishing communication with the external host 3 via a communication network compliant with any standard, such as a wireless LAN (Local Area Network), wired LAN, CAN (Controller Area Network), LIN (Local Interconnect Network), or FlexRay®.

[0030] The configuration of host 3, and the connection and positional relationship between host 3 and the distance measuring device 1, are arbitrary. Host 3 may be, for example, an ECU (Engine Control Unit) mounted on an automobile or the like when the distance measuring device 1 is mounted on an automobile or the like. Also, when the distance measuring device 1 is mounted on an autonomous mobile robot such as a household pet robot, a robotic vacuum cleaner, an unmanned aerial vehicle, or a follow-me transport robot, host 3 may be a control device or the like that controls the autonomous mobile robot. Host 3 may be an external device attached to the distance measuring device 1, or it may be a cloud server or the like that is located separately from the distance measuring device 1.

[0031] Figure 2 is a block diagram showing the detailed configuration of the light-emitting unit 12. The light-emitting unit 12 includes a light-emitting element array 31 having a plurality of light-emitting elements 30, a timing control circuit 32 that instructs the light-emitting timing of the light-emitting elements 30, and a drive circuit 33 that drives the light-emitting elements 30.

[0032] The light-emitting element 30 is, for example, a VCSEL (Vertical Cavity Surface Emitting Laser). The multiple light-emitting elements 30 in Figure 2 are arranged in two dimensions in the light-emitting element array 31. In the example in Figure 2, the light-emitting elements 30 are arranged in a first direction X (horizontal direction in Figure 2) and a second direction Y (vertical direction in Figure 2). However, the example in Figure 2 is not limited to the case where the multiple light-emitting elements 30 are arranged in one dimension (i.e., in one row or one column). In this specification, the light-emitting element 30 is sometimes referred to as an LD (Laser Diode).

[0033] The timing control circuit 32 drives the drive circuit 33 to drive the light-emitting elements 30 based on a clock signal or the like supplied from the control unit 11. The drive circuit 33 drives the light-emitting elements 30 arranged in multiple rows, for example, one row at a time, to make them light up. Drive lines SD extend from the drive circuit 33 to each row of the light-emitting element array 31. The drive circuit 33 may make multiple rows of light-emitting elements 30 light up simultaneously.

[0034] The light-emitting section 12 in Figure 2 may also have a configuration that includes a drive circuit that causes each row of light-emitting elements 30 to emit light.

[0035] In this specification, a group of light-emitting elements 30 in one row (or one column) driven by the drive circuit 33 is also referred to as a light-emitting element group 35. The light-emitting element array section 31 includes a plurality of light-emitting element groups 35.

[0036] As described above, the light-emitting unit 12 can emit light L1 within any range of the light-emitting element array unit 31 by the drive circuit 33.

[0037] Figure 3 is a block diagram showing the detailed configuration of the light-receiving unit 22. The light-receiving unit 22 includes a pixel array unit 41 having a plurality of light-receiving elements (pixels) 40, a timing control circuit 42 that instructs the light-receiving timing of the light-receiving elements 40, a drive circuit 43 that drives the light-receiving elements 40, and an output circuit 44 that outputs a detection signal based on the light detected by the light-receiving elements 40.

[0038] The light-receiving element 40 is, for example, a SPAD (Single Photon Avalanche Diode). The multiple light-receiving elements 40 in Figure 3 are arranged in two dimensions in the pixel array section 41. In the example in Figure 3, the light-receiving elements 40 are arranged in a first direction X (horizontal direction in Figure 3) and a second direction Y (vertical direction in Figure 3). However, the example in Figure 3 is not limited to the case where the multiple light-receiving elements 40 are arranged in one dimension (i.e., in one row or one column).

[0039] The timing control circuit 42 drives the light-receiving elements 40 to the drive circuit 43 based on a clock signal or the like supplied from the control unit 11. The drive circuit 43 drives the light-receiving elements 40 arranged in multiple rows, for example, one row at a time. Drive lines LD extend from the drive circuit 43 to each row of the pixel array section 41. The drive circuit 43 may drive multiple rows of light-receiving elements 40 simultaneously. The output circuit 44 outputs the detection signal to a subsequent signal processing circuit or the like. Note that the light-receiving section 22 in Figure 3 may be configured to drive the light-receiving elements 40 column by column.

[0040] Each of the plurality of light receiving elements 40 is connected to a pixel circuit or the like not shown in FIG. 3. Further, a predetermined voltage (hereinafter also referred to as a recharge voltage) is applied to the light receiving element 40 from a drive circuit 43 or the like. The recharge voltage is, for example, a power supply voltage. A recharge circuit that applies the recharge voltage may be connected to the light receiving element 40 under the control of a drive circuit 33 or the like.

[0041] When light is incident on the light receiving element 40 in a state where the recharge voltage is applied, the voltage of the light receiving element 40 rapidly fluctuates (for example, decreases) due to photoelectric conversion. The pixel circuit detects the voltage fluctuation of the light receiving element 40. Note that the pixel circuit may detect a current based on photoelectric conversion (hereinafter also referred to as a photocurrent) from the light receiving element 40. In this specification, a state where light is incident on the light receiving element 40 and voltage fluctuation occurs due to photoelectric conversion, or a state where a photocurrent is detected, is also referred to as light reception.

[0042] When the pixel circuit detects a voltage fluctuation (or a photocurrent) of the light receiving element 40, it generates a detection signal. The detection signal is output to an output circuit 44 when a selection signal is input from a drive circuit 33 or the like. Thereby, a plurality of pixel circuits can output detection signals synchronously. Note that the plurality of pixel circuits may output detection signals to the output circuit 44 asynchronously at the timing when each generates a detection signal.

[0043] Since the voltage of the light receiving element 40 is in a decreased state immediately after light reception, it cannot receive incident light. When the recharge voltage is applied to the light receiving element 40 after light reception, the light receiving element 40 becomes capable of receiving incident light again.

[0044] As described above, in the light receiving unit 22, the drive circuit 43 makes the plurality of light receiving elements 40 capable of receiving light, so that the reflected light L2 can be received in an arbitrary range of the pixel array unit 41.

[0045] In this specification, a group of light receiving elements 40 in one row (or one column) driven by the drive circuit 43 is also referred to as a light receiving element group 45. The pixel array unit 41 includes a plurality of light receiving element groups 45.

[0046] FIGS. 4A and 4B are diagrams for explaining the distance measuring method of the distance measuring device 1. The distance measuring device 1 can measure distance, for example, by the Solid-State method. The distance measuring device 1 emits outgoing light L1 within a predetermined distance measuring range A1 for distance measurement. More specifically, the light emitting unit 12 causes one or more light emitting element groups 35 to emit light, and emits the outgoing light L1 to the irradiation region A2 within the distance measuring range A1. At this time, in order to improve the light receiving efficiency, it is desirable that the light receiving unit 22 has one or more light receiving element groups 45 corresponding to the irradiation region A2 capable of receiving light.

[0047] FIGS. 4A and 4B illustrate the above-described distance measuring range A1 and irradiation region A2. The irradiation region A2 is, for example, a range extending in the first direction X. The light emitting unit 12 can irradiate the irradiation region A2 with the outgoing light L1, for example, by causing one or more light emitting element groups 35 to emit light. Further, the light emitting unit 12 can move the irradiation region A2 along the second direction Y, for example, by changing the light emitting element group 35 that emits light along the second direction Y. Thereby, the distance measuring device 1 can scan the distance measuring range A1.

[0048] Further, in order to improve the light receiving efficiency of the light receiving unit 22, it is desirable that the optical characteristics of the light emitting unit 12 and the projection lens 13 and the light receiving unit 22 and the light receiving lens 21 are substantially the same. As the above-described realization method, a plurality of methods can be considered.

[0049] As a first method, there is a method in which the light emitting element array unit 31 and the pixel array unit 41 are made the same size, and the same lens is used for the projection lens 13 and the light receiving lens 21. However, it is difficult to design and manufacture the light emitting element array unit 31 and the pixel array unit 41 that satisfy the conditions of the first method, and problems also occur in terms of cost.

[0050] The second method involves making the light-emitting element array 31 and the pixel array 41 have the same aspect ratio, and using two types of lenses with the same optical characteristics for the light-emitting lens 13 and the light-receiving lens 21. Compared to the first method, the second method also simplifies the design of the distance measuring device 1. However, the size of the light-emitting element array 31 must be made to match the aspect ratio of the pixel array 41, making it difficult to miniaturize the light-emitting unit 12. In addition, the handling of the light-emitting unit 12 deteriorates, and manufacturing costs increase. Furthermore, it becomes difficult to achieve uniformity in the performance of the multiple light-emitting elements 30.

[0051] A third method involves using a diffuser 14. The diffuser 14 can diffuse the emitted light L1 in at least one direction. This eliminates the need to make the aspect ratios of the light-emitting element array 31 and the pixel array 41 the same, simplifying the design and manufacturing of the distance measuring device 1. Furthermore, the diffuser 14 expands the irradiation range of the emitted light L1, allowing the light-emitting unit 12 to be miniaturized.

[0052] Figures 5A and 5B illustrate a distance measurement method using a diffuser 14. As shown in Figure 5A, the diffuser 14 diffuses the emitted light L1 irradiated through the light projection lens 13, for example, in a first direction X.

[0053] As shown in Figure 5B, the light-emitting section 12 can be fitted with a light-emitting element array section 31 in which the ratio of the width in the first direction X to the width in the second direction Y is smaller than the ratio of the width in the first direction X to the width in the second direction Y in the light-receiving section 22 (pixel array section 41).

[0054] The diffuser 14 can expand the area illuminated by the emitted light L1 in the distance measurement range A1 (i.e., the illuminated area A2) compared to when the emitted light L1 is emitted directly from the light projection lens 13 into the distance measurement range A1. This allows the width of the illuminated area A2 to correspond to the width of the area in the distance measurement range A1 in which the light receiving unit 22 can receive reflected light L2.

[0055] Figure 6 illustrates the challenges in distance measurement using the diffuser 14. Figure 6 shows a pixel array section 41 that receives reflected light L2. The pixel array section 41 enables the three light-receiving element groups 45a, 45b, and 45c in Figure 6 to receive light at different timings. In this specification, the range in which light can be received by the light-receiving element group 45 is also called the light-receiving range (or the minimum light-receiving range of the pixel array section 41).

[0056] The light-receiving element group 45a is located in the central part 41a of the pixel array section 41. The light-receiving element groups 45b and 45c are located at the ends of the pixel array section 41. Specifically, the light-receiving element group 45b is located at one end 41b of the pixel array section 41, and the light-receiving element group 45c is located at the other end 41c of the pixel array section 41. In this specification, the end 41b located at the bottom of Figure 6 is also referred to as the lower end of the pixel array section 41, and the end 41c located at the top of Figure 6 is also referred to as the upper end of the pixel array section 41.

[0057] Furthermore, Figure 6 illustrates the illumination regions A3a, A3b, and A3c of the reflected light L2 incident on the pixel array 41 at the timing when each of the light-receiving element groups 45a, 45b, and 45c becomes capable of receiving light.

[0058] The area where the light-receiving range of the light-receiving element group 45a (hereinafter also simply referred to as the light-receiving element group 45a) overlaps with the illumination area A3a is the distance-measuring area A4a, where the distance can be measured by the distance measuring device 1. Similarly, the area where the light-receiving element group 45b overlaps with the illumination area A3b is the distance-measuring area A4b, and the area where the light-receiving element group 45c overlaps with the illumination area A3c is the distance-measuring area A4c.

[0059] As shown in Figure 6, the light-receiving element group 45a has a distance-measuring region A4a that covers almost its entire surface. That is, since reflected light L2 can be received over almost the entire surface of the light-receiving element group 45a, the distance measuring device 1 can measure distance with high light reception efficiency.

[0060] On the other hand, in the photodetector group 45b, the distortion of the diffuser 14 causes the illumination area A3b to become a curved, bow-shaped region. As a result, a region is created where the photodetector group 45b and the illumination area A3b do not overlap (referred to as a distortion shift in this specification), and the distance-measurable area A4b becomes narrower than the distance-measurable area A4a. Similarly, the distance-measurable area A4c becomes narrower than the distance-measurable area A4a. Therefore, the photodetector groups 45b and 45c have lower light-receiving efficiency than the photodetector group 45a.

[0061] Therefore, in the distance measuring device 1 according to the first embodiment of this disclosure, the light receiving efficiency of the end portion of the pixel array portion 41 (i.e., the light receiving element group 45b, etc.) is improved by the distance measuring method described below.

[0062] Figures 7A and 7B show the distance measuring method of the distance measuring device 1 according to the first embodiment of the present disclosure. Figure 7A shows the light-receiving element group 45a, the illumination area A3d corresponding to the illumination area A3a in Figure 6, and the distance-measuring area A4d where the light-receiving element group 45a and the illumination area A3d overlap.

[0063] As shown in Figure 7A, the width of the irradiation area A3d in the second direction Y is greater than the width of the photodetector group 45 in the second direction Y. In other words, the distance measuring device 1 according to the first embodiment of this disclosure irradiates the emitted light L1 over a wider area in the second direction Y than the light receiving range of the photodetector group 45.

[0064] In Figure 7A, the light-receiving element group 45a has a distance-measuring area A4d that is almost entirely covered, similar to Figure 6.

[0065] Figure 7B illustrates the photodetector group 45b, the illumination region A3e corresponding to the illumination region A3b in Figure 6, and the distance-measuring region A4e where the photodetector group 45b and the illumination region A3e overlap. The width of the illumination region A3e in the second direction Y is, for example, the same as the width of the illumination region A3d in the second direction Y in Figure 7A.

[0066] The illumination region A3e, like the illumination region A3b in Figure 6, is a curved region due to distortion. However, the illumination region A3e is wider in the second direction Y than the illumination region A3b in Figure 6. Therefore, as shown in Figure 7B, the distance-measurable region A4e can be expanded compared to the distance-measurable region A4b in Figure 6.

[0067] Thus, the distance measuring device 1 according to the first embodiment of this disclosure irradiates the emitted light L1 over a wider area in the scanning direction (second direction Y in the example of Figure 7A) than the minimum light receiving range of the light receiving unit 22. As a result, the distance measuring device 1 can expand the range over which distances can be measured. In particular, the distance measuring device 1 can improve the light receiving efficiency and thus the distance measurement accuracy at the edges of the distance measuring range A1 where distortion shift of the diffuser 14 occurs.

[0068] (Second Embodiment) There are several possible methods for realizing the distance measurement method shown in Figures 7A and 7B. In the second embodiment of this disclosure, one example will be described.

[0069] Figures 8A and 8B show the distance measuring method of the distance measuring device 1 according to the second embodiment of the present disclosure. In Figure 8A, similar to Figure 7A, the photodetector group 45a, the illumination area A3d, and the distance-measurable area A4d are shown. In Figure 8B, similar to Figure 7B, the photodetector group 45b, the illumination area A3e, and the distance-measurable area A4e are shown.

[0070] In Figure 8A, the light-receiving unit 22 enables the light-receiving element group 45a to receive light, while the light-emitting unit 12 causes the light-emitting element groups 35a, 35b, and 35c to emit light. That is, the irradiation area A3d in Figure 8A is irradiated with reflected light L2 based on the emitted light L1 emitted by the light-emitting element groups 35a to 35c.

[0071] The light-emitting element groups 35a to 35c are arranged, for example, adjacent to each other. The light-emitting element groups 35a to 35c may start emitting light simultaneously. Alternatively, the light-emitting element groups 35a to 35c may be made to emit light such that at least a portion of their emission periods overlap. That is, in the second embodiment, a plurality of light-emitting elements 30 arranged in the first direction X and two or more light-emitting elements 30 adjacent to each other in the second direction Y emit light simultaneously.

[0072] In other words, in the distance measurement method shown in Figure 8A, the illumination area A3d is expanded in the second direction Y beyond the light-receiving range of the light-receiving element group 45a by emitting light from more light-emitting element groups 35 than the light-receiving element group 45a. As a result, the light-receiving unit 22 can receive reflected light L2 over a range that is, for example, more than twice the minimum light-receiving range.

[0073] Similarly, in Figure 8B, the light-receiving element group 45b is capable of receiving light, while the illumination area A3e receives reflected light L2 based on the emitted light L1 from the light-emitting element groups 35d, 35e, and 35f. This allows the distance-measurable area A4e to be expanded compared to the distance-measurable area A4b in Figure 6.

[0074] In Figures 8A and 8B, one group of photodetectors 45 is made capable of receiving light at each timing of receiving reflected light L2, but this is not limited to this, and multiple groups of photodetectors 45 may be made capable of receiving light. In addition to increasing the number of light-emitting element groups 35, the beam diameter of the emitted light L1 emitted from the light-emitting element groups 35 may be increased to expand the irradiation area A3e, etc.

[0075] Figure 9 is a diagram illustrating the operation of the light-emitting unit 12 and the light-receiving unit 22 according to the second embodiment of the present disclosure. In Figure 9, the horizontal axis represents the light-receiving element group 45 (SPAD Line), and the vertical axis represents the light-emitting element group 35 (VCSEL Ch). In Figure 9, the light-emitting element group 35 that emits light is shown with dot hatches, and the light-receiving element group 45 that enables light reception is shown with a thick frame.

[0076] As shown in Figure 9, when the light-receiving element group 45b located at the end 41b or 41c receives light, for example, the light-emitting element group 35d located at the position corresponding to the light-receiving element group 45b, the light-emitting element group 35e located adjacent to the light-emitting element group 35d towards the center of the light-emitting element array 31, and the light-emitting element group 35f located adjacent to the light-emitting element group 35e towards the center of the light-emitting element array 31 are made to emit light. Also, when the light-receiving element group 45a located at the central part 41a receives light, the light-emitting element group 35a located at the position corresponding to the light-receiving element group 45a, and the light-emitting element groups 35b and 35c located adjacent to the light-emitting element group 35a are made to emit light.

[0077] The light-emitting unit 12 may emit light from any number of light-emitting groups 35, not limited to the method described in Figure 9. Furthermore, the relative positions of the multiple light-emitting groups 35 are also arbitrary.

[0078] Thus, in the second embodiment of this disclosure, the irradiation area of ​​the reflected light L2 is expanded in the scanning direction by emitting light from more light-emitting elements 35 than from the light-receiving element group 45 that are capable of receiving light. This improves the light-receiving efficiency of the distance measuring device 1 and improves the distance measuring accuracy.

[0079] (Third Embodiment) A third embodiment of the present disclosure describes another method for realizing the distance measurement method shown in Figures 7A and 7B. Figure 10 is a diagram illustrating the distance measurement method according to the third embodiment of the present disclosure. Figure 10 shows a light-emitting unit 12, a light-emitting lens 13, emitted light L1, and the focal point fcs of the light-emitting lens 13. Note that the diffuser 14 is not shown in Figure 10.

[0080] The light-emitting unit 12 in Figure 10 is positioned at a location different from the focal point fcs of the projection lens 13 so as to blur the emitted light L1 in the scanning direction (for example, the second direction Y). In the example in Figure 10, the light-emitting unit 12 is positioned between the focal point fcs and the projection lens 13, but the light-emitting unit 12 may be positioned further away from the projection lens 13 than the focal point fcs. Also, the amount of blur at both ends of the emitted light L1 in the first direction X may be greater than the amount of blur at the center of the first direction X. This allows the projection lens 13 to diffuse the emitted light L1 in the scanning direction.

[0081] The positions of the light-emitting lens 13 and the light-emitting unit 12 may be adjusted dynamically. For example, the distance measuring device 1 may have a mechanical drive unit that adjusts the position of the light-emitting lens 13.

[0082] The distance measuring method according to the third embodiment of this disclosure does not require the emission of multiple light-emitting element groups 35, and thus can reduce power consumption compared to the distance measuring method according to the second embodiment. However, in the distance measuring method according to the third embodiment of this disclosure, multiple light-emitting element groups 35 may be emitted, as in the second embodiment.

[0083] (Fourth Embodiment) Figure 11 is a diagram illustrating the operation of the light-emitting unit 12 and the light-receiving unit 22 according to the fourth embodiment of the present disclosure. Similar to Figure 9, Figure 11 illustrates the operation of the light-emitting element array 31 in the range corresponding to the end portion 41c and the central portion 41a of the pixel array 41. Note that the end portion 41b is not shown in Figure 11.

[0084] As shown in Figure 11, in the fourth embodiment of the present disclosure, the number of light-emitting groups 35 that emit light in the area corresponding to the central part 41a is less than the number of light-emitting groups 35 that emit light in the area corresponding to the end part 41c.

[0085] As shown in Figure 6, the central portion 41a is only slightly affected by distortion, so high light reception efficiency can be obtained without expanding the irradiation area of ​​the reflected light L2. For this reason, in the method shown in Figure 11, power consumption is reduced by reducing the number of light-emitting element groups 35 that emit light in the area corresponding to the central portion 41a.

[0086] (Fifth Embodiment) As in the fourth embodiment of this disclosure, when increasing or decreasing the number of light-emitting element groups 35 that emit light during scanning, the light emission power increases as the number of light-emitting element groups 35 increases. As a result, at the edges of the distance measurement range A1, the light emission power may become excessive and exceed the laser safety standard (e.g., eye-safe band).

[0087] Therefore, in the fifth embodiment of this disclosure, the light emission power of each individual light-emitting element 30 is controlled according to the number of light-emitting elements 30 that are emitted simultaneously. Specifically, when there are many light-emitting element groups 35 that emit light simultaneously, the light emission power of each individual light-emitting element group 35 is reduced. This makes it possible to emit light L1 within the range of the laser safety standards even when there are many light-emitting elements in the light-emitting element groups 35. Also, when there are few light-emitting element groups 35, the light emission power of the light-emitting element groups 35 may be increased.

[0088] (Sixth Embodiment) Figure 12 is a diagram showing a distance measuring method of a distance measuring device 1 according to the sixth embodiment of the present disclosure. The distance measuring device 1 in Figure 12 has a diffuser 14a that diffuses the emitted light L1 in the second direction Y. In the distance measuring method of Figure 12, the light-emitting unit 12 sequentially emits light from the light-emitting element 30 so that the irradiation area A2 moves along the first direction X, and the light-receiving unit 22 sequentially makes the light-receiving element 40 capable of receiving light so that the light-receiving range moves along the first direction X.

[0089] In the sixth embodiment, by irradiating the emitted light L1 over a wider area in the scanning direction (i.e., the first direction X) than the minimum light-receiving range of the light-receiving unit 22, the light-receiving efficiency can be improved at the edges of the distance-measuring range A1, similar to the first embodiment.

[0090] (Application Examples) The technology disclosed herein can be applied to a variety of products. For example, the technology disclosed herein may be implemented as a device mounted on any type of mobile vehicle, such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility devices, airplanes, drones, ships, robots, construction machinery, or agricultural machinery (tractors).

[0091] Figure 13 is a block diagram showing a schematic configuration example of a vehicle control system 7000, which is an example of a mobile control system to which the technology of this disclosure may be applied. The vehicle control system 7000 comprises a plurality of electronic control units connected via a communication network 7010. In the example shown in Figure 13, the vehicle control system 7000 comprises a drive system control unit 7100, a body system control unit 7200, a battery control unit 7300, an external information detection unit 7400, an internal information detection unit 7500, and an integrated control unit 7600. The communication network 7010 connecting these plurality of control units may be an in-vehicle communication network conforming to any standard such as CAN (Controller Area Network), LIN (Local Interconnect Network), LAN (Local Area Network), or FlexRay®.

[0092] Each control unit comprises a microcomputer that performs calculations according to various programs, a storage unit that stores programs executed by the microcomputer or parameters used in various calculations, and a drive circuit that drives various controlled devices. Each control unit is equipped with a network interface for communication with other control units via the communication network 7010, and a communication interface for communication with devices or sensors inside or outside the vehicle via wired or wireless communication. Figure 13 shows the functional configuration of the integrated control unit 7600, which includes a microcomputer 7610, a general-purpose communication interface 7620, a dedicated communication interface 7630, a positioning unit 7640, a beacon receiver 7650, an in-vehicle equipment interface 7660, an audio / image output unit 7670, an in-vehicle network interface 7680, and a storage unit 7690. Other control units similarly include a microcomputer, a communication interface, and a storage unit.

[0093] The drivetrain control unit 7100 controls the operation of devices related to the vehicle's drivetrain according to various programs. For example, the drivetrain control unit 7100 functions as a control device for generating driving force for the vehicle, such as an internal combustion engine or a drive motor; a driving force transmission mechanism for transmitting driving force to the wheels; a steering mechanism for adjusting the steering angle of the vehicle; and a braking device for generating braking force for the vehicle. The drivetrain control unit 7100 may also function as a control device such as an ABS (Antilock Brake System) or an ESC (Electronic Stability Control).

[0094] A vehicle state detection unit 7110 is connected to the drive system control unit 7100. The vehicle state detection unit 7110 includes, for example, a gyro sensor for detecting the angular velocity of the axial rotation motion of the vehicle body, an acceleration sensor for detecting the acceleration of the vehicle, or at least one of the sensors for detecting the amount of operation of the accelerator pedal, the amount of operation of the brake pedal, the steering angle of the steering wheel, the engine speed, or the rotational speed of the wheels. The drive system control unit 7100 performs calculation processing using the signals input from the vehicle state detection unit 7110 and controls the internal combustion engine, drive motor, electric power steering system, brake system, etc.

[0095] The body system control unit 7200 controls the operation of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 7200 functions as a control device for a keyless entry system, a smart key system, a power window system, or various lamps such as headlights, reverse lights, brake lights, turn signals, or fog lights. In this case, the body system control unit 7200 may receive radio waves transmitted from a portable device that replaces a key or signals from various switches. The body system control unit 7200 receives these radio waves or signals and controls the vehicle's door lock system, power window system, lamps, etc.

[0096] The battery control unit 7300 controls the secondary battery 7310, which is the power source for the drive motor, according to various programs. For example, the battery control unit 7300 receives information such as battery temperature, battery output voltage, or remaining battery capacity from the battery device equipped with the secondary battery 7310. The battery control unit 7300 uses these signals to perform calculations and controls the temperature of the secondary battery 7310 or the cooling device provided in the battery device.

[0097] The external information detection unit 7400 detects information from outside the vehicle equipped with the vehicle control system 7000. For example, at least one of the imaging unit 7410 and the external information detection unit 7420 is connected to the external information detection unit 7400. The imaging unit 7410 includes at least one of the following: a Time of Flight (ToF) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. The external information detection unit 7420 includes at least one of the following: an environmental sensor for detecting the current weather or climate, or an ambient information detection sensor for detecting other vehicles, obstacles, or pedestrians around the vehicle equipped with the vehicle control system 7000.

[0098] The environmental sensor may be at least one of the following: a raindrop sensor for detecting rain, a fog sensor for detecting fog, a sunshine sensor for detecting the degree of sunlight, and a snow sensor for detecting snowfall. The ambient information detection sensor may be at least one of the following: an ultrasonic sensor, a radar device, and a LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) device. These imaging unit 7410 and external information detection unit 7420 may be provided as independent sensors or devices, or as a device in which multiple sensors or devices are integrated.

[0099] Here, Figure 14 shows examples of the installation locations of the imaging unit 7410 and the external information detection unit 7420. The imaging units 7910, 7912, 7914, 7916, and 7918 are installed, for example, at least one of the following locations on the vehicle 7900: the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield inside the passenger compartment. The imaging unit 7910 installed on the front nose and the imaging unit 7918 installed on the upper part of the windshield inside the passenger compartment mainly acquire images of the front of the vehicle 7900. The imaging units 7912 and 7914 installed on the side mirrors mainly acquire images of the sides of the vehicle 7900. The imaging unit 7916 installed on the rear bumper or back door mainly acquires images of the rear of the vehicle 7900. The imaging unit 7918 installed on the upper part of the windshield inside the passenger compartment is mainly used for detecting preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, or lanes.

[0100] Figure 14 shows an example of the imaging range of each imaging unit 7910, 7912, 7914, and 7916. Imaging range a shows the imaging range of imaging unit 7910 located on the front nose, imaging ranges b and c show the imaging ranges of imaging units 7912 and 7914 located on the side mirrors, respectively, and imaging range d shows the imaging range of imaging unit 7916 located on the rear bumper or back door. For example, by superimposing the image data captured by imaging units 7910, 7912, 7914, and 7916, an overhead view image of the vehicle 7900 can be obtained.

[0101] The external information detection units 7920, 7922, 7924, 7926, 7928, and 7930, which are installed on the front, rear, sides, corners, and the upper part of the windshield inside the vehicle 7900, may be, for example, ultrasonic sensors or radar devices. The external information detection units 7920, 7926, and 7930, which are installed on the front nose, rear bumper, back door, and the upper part of the windshield inside the vehicle 7900, may be, for example, LIDAR devices. These external information detection units 7920 to 7930 are mainly used for detecting preceding vehicles, pedestrians, or obstacles.

[0102] Returning to Figure 13, the explanation continues. The external information detection unit 7400 causes the imaging unit 7410 to capture images of the area outside the vehicle and receives the captured image data. The external information detection unit 7400 also receives detection information from the connected external information detection unit 7420. If the external information detection unit 7420 is an ultrasonic sensor, radar device, or LIDAR device, the external information detection unit 7400 emits ultrasonic waves or electromagnetic waves and receives information on the received reflected waves. Based on the received information, the external information detection unit 7400 may perform object detection processing such as detecting people, vehicles, obstacles, signs, or characters on the road surface, or distance detection processing. Based on the received information, the external information detection unit 7400 may perform environmental recognition processing to recognize rainfall, fog, or road surface conditions. Based on the received information, the external information detection unit 7400 may calculate the distance to an object outside the vehicle.

[0103] Furthermore, the external information detection unit 7400 may perform image recognition processing or distance detection processing to recognize people, vehicles, obstacles, signs, or characters on the road surface based on the received image data. The external information detection unit 7400 may perform distortion correction or alignment processing on the received image data, and may also synthesize image data captured by different imaging units 7410 to generate an overhead view image or a panoramic image. The external information detection unit 7400 may also perform viewpoint transformation processing using image data captured by different imaging units 7410.

[0104] The in-vehicle information detection unit 7500 detects information inside the vehicle. The in-vehicle information detection unit 7500 is connected to, for example, a driver status detection unit 7510 that detects the driver's state. The driver status detection unit 7510 may include a camera that images the driver, a biosensor that detects the driver's biometric information, or a microphone that collects sounds inside the vehicle. The biosensor is installed, for example, on the seat or steering wheel and detects the biometric information of an occupant sitting in the seat or a driver holding the steering wheel. Based on the detection information input from the driver status detection unit 7510, the in-vehicle information detection unit 7500 may calculate the driver's level of fatigue or concentration, or determine whether the driver is dozing off. The in-vehicle information detection unit 7500 may perform processing such as noise cancellation on the collected audio signals.

[0105] The integrated control unit 7600 controls the overall operation of the vehicle control system 7000 according to various programs. An input unit 7800 is connected to the integrated control unit 7600. The input unit 7800 is implemented by a device that can be operated by the passenger, such as a touch panel, buttons, a microphone, a switch, or a lever. The integrated control unit 7600 may also receive data obtained by voice recognition of voice input from the microphone. The input unit 7800 may be, for example, a remote control device using infrared or other radio waves, or an externally connected device such as a mobile phone or PDA (Personal Digital Assistant) that is compatible with the operation of the vehicle control system 7000. The input unit 7800 may be, for example, a camera, in which case the passenger can input information by gesture. Alternatively, data obtained by detecting the movement of a wearable device worn by the passenger may be input. Furthermore, the input unit 7800 may include, for example, an input control circuit that generates an input signal based on the information input by the passenger using the above input unit 7800 and outputs it to the integrated control unit 7600. Passengers and others can input various data or instruct the vehicle control system 7000 to perform processing operations by operating this input unit 7800.

[0106] The storage unit 7690 may include a ROM (Read Only Memory) for storing various programs executed by a microcomputer, and a RAM (Random Access Memory) for storing various parameters, calculation results, or sensor values. The storage unit 7690 may also be implemented using a magnetic storage device such as an HDD (Hard Disk Drive), a semiconductor storage device, an optical storage device, or a magneto-optical storage device.

[0107] The general-purpose communication interface 7620 is a general-purpose communication interface that mediates communication between the external environment 7750 and various devices present in the external environment 7750. The general-purpose communication interface 7620 may implement cellular communication protocols such as GSM (Global System of Mobile communications), WiMAX (registered trademark), LTE (registered trademark) (Long Term Evolution), or LTE-A (LTE-Advanced), or other wireless communication protocols such as wireless LAN (also known as Wi-Fi (registered trademark)) and Bluetooth (registered trademark). The general-purpose communication interface 7620 may connect, for example, to devices (e.g., application servers or control servers) located on an external network (e.g., the Internet, a cloud network, or a carrier-specific network) via a base station or access point. Furthermore, the general-purpose communication I / F 7620 may connect to terminals located near the vehicle (for example, terminals belonging to the driver, pedestrians, or shops, or MTC (Machine Type Communication) terminals) using, for example, P2P (Peer To Peer) technology.

[0108] The dedicated communication interface 7630 is a communication interface that supports communication protocols developed for use in vehicles. The dedicated communication interface 7630 may implement standard protocols such as WAVE (Wireless Access in Vehicle Environment), DSRC (Dedicated Short Range Communications), or cellular communication protocols, which are combinations of lower-layer IEEE 802.11p and upper-layer IEEE 1609. The dedicated communication interface 7630 typically performs V2X communication, a concept that includes one or more of the following: vehicle-to-vehicle communication, vehicle-to-infrastructure communication, vehicle-to-home communication, and vehicle-to-pedestrian communication.

[0109] The positioning unit 7640 performs positioning by receiving, for example, GNSS (Global Navigation Satellite System) signals from GNSS satellites (for example, GPS signals from GPS (Global Positioning System) satellites) and generates location information including the vehicle's latitude, longitude, and altitude. The positioning unit 7640 may also determine its current location by exchanging signals with a wireless access point, or it may acquire location information from a terminal such as a mobile phone, PHS, or smartphone that has a positioning function.

[0110] The beacon receiver 7650 receives radio waves or electromagnetic waves transmitted from, for example, a radio station installed on a road, and acquires information such as the current location, traffic congestion, road closures, or travel time. The functions of the beacon receiver 7650 may also be included in the dedicated communication interface 7630 described above.

[0111] The in-vehicle equipment interface 7660 is a communication interface that mediates connections between the microcomputer 7610 and various in-vehicle equipment 7760 located inside the vehicle. The in-vehicle equipment interface 7660 may establish a wireless connection using wireless communication protocols such as wireless LAN, Bluetooth®, NFC (Near Field Communication), or WUSB (Wireless USB). Furthermore, the in-vehicle equipment I / F 7660 may establish a wired connection such as USB (Universal Serial Bus), HDMI (High-Definition Multimedia Interface), or MHL (Mobile High-definition Link) via connection terminals (and, if necessary, cables) not shown. The in-vehicle equipment 7760 may include, for example, at least one of the following: a mobile device or wearable device owned by a passenger, or an information device brought into or installed in the vehicle. The in-vehicle equipment 7760 may also include a navigation device that searches for a route to any destination. The in-vehicle equipment I / F 7660 exchanges control signals or data signals with these in-vehicle equipment 7760s.

[0112] The in-vehicle network interface 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The in-vehicle network interface 7680 transmits and receives signals and other data in accordance with a predetermined protocol supported by the communication network 7010.

[0113] The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 according to various programs based on information acquired via at least one of the general-purpose communication I / F 7620, dedicated communication I / F 7630, positioning unit 7640, beacon receiver 7650, in-vehicle equipment I / F 7660, and in-vehicle network I / F 7680. For example, the microcomputer 7610 may calculate control target values ​​for the drive force generator, steering mechanism, or braking device based on acquired information from inside and outside the vehicle, and output control commands to the drive system control unit 7100. For example, the microcomputer 7610 may perform coordinated control aimed at realizing ADAS (Advanced Driver Assistance System) functions, including vehicle collision avoidance or impact mitigation, following driving based on distance between vehicles, maintaining vehicle speed, vehicle collision warning, or vehicle lane departure warning. Furthermore, the microcomputer 7610 may perform cooperative control for purposes such as autonomous driving, where the vehicle drives autonomously without driver intervention, by controlling the drive force generating device, steering mechanism, or braking device, etc., based on the acquired information about the vehicle's surroundings.

[0114] The microcomputer 7610 may generate three-dimensional distance information between the vehicle and surrounding structures, people, and other objects based on information acquired via at least one of the general-purpose communication I / F 7620, dedicated communication I / F 7630, positioning unit 7640, beacon receiver 7650, in-vehicle equipment I / F 7660, and in-vehicle network I / F 7680, and create local map information including surrounding information of the vehicle's current location. The microcomputer 7610 may also predict dangers such as vehicle collision, proximity of pedestrians, or entry into a closed road based on the acquired information, and generate a warning signal. The warning signal may be, for example, a signal to generate a warning sound or to illuminate a warning lamp.

[0115] The audio-image output unit 7670 transmits at least one of audio and image output signals to an output device capable of visually or audibly notifying the vehicle's occupants or those outside the vehicle. In the example shown in Figure 13, the output devices are exemplified as an audio speaker 7710, a display unit 7720, and an instrument panel 7730. The display unit 7720 may include, for example, at least one of an onboard display and a head-up display. The display unit 7720 may also have an AR (Augmented Reality) display function. The output device may be other devices besides these, such as headphones, wearable devices such as glasses-type displays worn by occupants, projectors, or lamps. If the output device is a display device, the display device visually displays the results obtained from various processes performed by the microcomputer 7610 or information received from other control units in various formats such as text, images, tables, and graphs. If the output device is an audio output device, the audio output device converts the audio signal, consisting of reproduced audio data or sound data, into an analog signal and outputs it audibly.

[0116] In the example shown in Figure 13, at least two control units connected via the communication network 7010 may be integrated into a single control unit. Alternatively, each control unit may be composed of multiple control units. Furthermore, the vehicle control system 7000 may include other control units not shown. Also, in the above description, some or all of the functions performed by one control unit may be assigned to other control units. In other words, as long as information is transmitted and received via the communication network 7010, predetermined calculation processing may be performed by any of the control units. Similarly, a sensor or device connected to one control unit may be connected to another control unit, and multiple control units may transmit and receive detection information to each other via the communication network 7010.

[0117] In the vehicle control system 7000 described above, the distance measuring device 1 according to this embodiment, as described with reference to Figure 1, can be applied to the imaging unit 7410 of the application example shown in Figure 13. The distance measuring device 1 according to this disclosure can, for example, measure the distance to a person or object with high accuracy.

[0118] Furthermore, this technology can take the following configurations: (1) A light-emitting device comprising: a light-emitting unit that emits light while scanning a band of light extending in a first direction in a second direction intersecting the first direction; and an optical element that diffuses the emitted band of light in the first direction, wherein the light-emitting unit spreads the band of light in the second direction so that at least a portion of the light contained in the band of light diffused by the optical element is received over a wider area than the minimum receiving range of a light-receiving device that receives reflected light reflected from an object. (2) The light-emitting device according to (1), wherein the light-emitting unit spreads the band of light in the second direction so that the reflected light is received over a range of at least twice the minimum receiving range of the light-receiving device. (3) The light-emitting device according to (1) or (2), wherein the light-emitting unit has a plurality of light-emitting elements arranged in the first direction and emitting light simultaneously to generate the band of light. (4) The plurality of light-emitting elements are arranged in a plurality in the first direction and a plurality in the second direction, and the light-emitting unit generates the band of light by simultaneously emitting light from two or more adjacent light-emitting elements in the second direction and a plurality of light-emitting elements arranged in the first direction, as described in (3). (5) The light-emitting unit controls the light-emitting power of each of the light-emitting elements according to the number of light-emitting elements that are emitted simultaneously, as described in (4). (6) The light-emitting unit lowers the light-emitting power of each of the light-emitting elements as the number of light-emitting elements in the second direction included in the band of light increases, as described in (5). (7) The light-emitting unit comprises an optical system for adjusting the focus of the band of light emitted from the light-emitting unit, and the optical element diffuses the band of light that has been focused by the optical system in the first direction, as described in any one of (1) to (6). (8) The light-emitting unit comprises an optical system for blurring the band of light emitted from the light-emitting unit in the second direction, as described in (7). (9) The light-emitting device according to (8), wherein the optical system makes the amount of blur at both ends of the band of light emitted from the light-emitting unit in the first direction greater than the amount of blur at the center in the first direction.(10) A distance measuring device comprising: a light-emitting unit that emits light while scanning a band of light extending in a first direction in a second direction intersecting the first direction; an optical element that diffuses the emitted band of light in the first direction; and a light-receiving unit that receives reflected light in which at least a portion of the light contained in the band of light diffused by the optical element is reflected by an object, wherein the light-emitting unit spreads the band of light in the second direction such that the reflected light is received over a wider area than the minimum light-receiving range of the light-receiving unit that receives reflected light in which at least a portion of the light contained in the band of light diffused by the optical element is reflected by an object. (11) The distance measuring device according to (10), wherein the light-receiving unit has a plurality of light-receiving elements arranged in the first direction and receiving the reflected light in the minimum light-receiving range. (12) The distance measuring device according to (11), wherein the light-receiving unit includes a plurality of light-receiving elements arranged in the first direction and has a plurality of light-receiving element groups that receive reflected light at a plurality of light-receiving timings, and the light-emitting unit includes a plurality of light-emitting elements arranged in the first direction and simultaneously emitting light to generate the band-shaped light, and has a plurality of light-emitting element groups that emit the band-shaped light at a plurality of light-emitting timings corresponding to the plurality of light-receiving timings, wherein at least a portion of the plurality of light-emitting element groups emit light, more light-emitting element groups than the light-receiving element groups that receive reflected light at the corresponding light-receiving timings. (13) The distance measuring device according to (12), wherein the plurality of light-emitting timings include a plurality of types of light-emitting timings in which the number of light-emitting element groups differs from each other.

[0119] The aspects of this disclosure are not limited to the individual embodiments described above, but include various modifications that a person skilled in the art could conceive, and the effects of this disclosure are not limited to those described above. In other words, various additions, modifications, and partial deletions are possible, as long as they do not depart from the conceptual idea and spirit of this disclosure derived from the claims and their equivalents.

[0120] 1 Distance measuring device, 2 Object to be measured, 3 Host, 10 Light-emitting device, 11 Control unit, 12 Light-emitting unit, 13 Projection lens, 14, 14a Diffuser, 20 Light-receiving device, 21 Light-receiving lens, 22 Light-receiving unit, 23 Calculation unit, 24 External interface, 30 Light-emitting element, 31 Light-emitting element array, 32 Timing control circuit, 33 Drive circuit, 35, 35a, 35b, 35c, 35d, 35e, 35f Light-emitting element group, 40 Light-receiving element, 41 Pixel array, 41a Center, 41b, 41c End, 42 Timing control circuit, 43 Drive circuit, 44 Output circuit, 45, 45a, 45b, 45c Light-receiving element group

Claims

1. A light-emitting device comprising: a light-emitting unit that emits light while scanning a band of light extending in a first direction in a second direction intersecting the first direction; and an optical element that diffuses the emitted band of light in the first direction, wherein the light-emitting unit spreads the band of light in the second direction such that at least a portion of the light contained in the band of light diffused by the optical element is received over a wider area than the minimum receiving range of a light-receiving device that receives reflected light reflected from an object.

2. The light-emitting unit spreads the band of light in the second direction so that the reflected light is received over a range of at least twice the minimum light-receiving range of the light-receiving device, as described in claim 1.

3. The light-emitting device according to claim 1, wherein the light-emitting section has a plurality of light-emitting elements arranged in the first direction and emitting light simultaneously to generate the band-shaped light.

4. The light-emitting device according to claim 3, wherein the plurality of light-emitting elements are arranged in a plurality in the first direction and a plurality in the second direction, and the light-emitting unit generates the band-shaped light by simultaneously emitting light from two or more adjacent light-emitting elements in the second direction and the plurality of light-emitting elements arranged in the first direction.

5. The light-emitting device according to claim 4, wherein the light-emitting unit controls the light-emitting power of each of the light-emitting elements according to the number of light-emitting elements that are emitted simultaneously.

6. The light-emitting device according to claim 5, wherein the light-emitting unit lowers the light-emitting power of each individual light-emitting element as the number of light-emitting elements in the second direction included in the band of light increases.

7. The light-emitting device according to claim 1, comprising an optical system for adjusting the focus of the band-shaped light emitted from the light-emitting unit, wherein the optical element diffuses the band-shaped light that has been focused by the optical system in a first direction.

8. The light-emitting device according to claim 7, wherein the optical system blurs the band of light emitted from the light-emitting unit in the second direction.

9. The light-emitting device according to claim 8, wherein the optical system makes the amount of blur at both ends in the first direction of the band of light emitted from the light-emitting unit greater than the amount of blur at the center in the first direction.

10. A distance measuring device comprising: a light-emitting unit that emits light while scanning a band of light extending in a first direction in a second direction intersecting the first direction; an optical element that diffuses the emitted band of light in the first direction; and a light-receiving unit that receives reflected light in which at least a portion of the light contained in the band of light diffused by the optical element is reflected by an object, wherein the light-emitting unit spreads the band of light in the second direction so that the reflected light is received over a wider area than the minimum light-receiving range of the light-receiving unit that receives reflected light in which at least a portion of the light contained in the band of light diffused by the optical element is reflected by an object.

11. The distance measuring device according to claim 10, wherein the light receiving unit has a plurality of light receiving elements arranged in the first direction and receiving the reflected light in the minimum light receiving range.

12. The distance measuring device according to claim 11, wherein the light receiving unit includes a plurality of light receiving elements arranged in the first direction, and has a plurality of light receiving element groups that receive reflected light at a plurality of light receiving timings, and the light emitting unit includes a plurality of light-emitting elements arranged in the first direction and simultaneously emitting light to generate the band-shaped light, and has a plurality of light-emitting element groups that emit the band-shaped light at a plurality of light-emitting timings corresponding to the plurality of light receiving timings, and at least a portion of the plurality of light-emitting element groups emit light, more of which emit light than the light receiving element groups that receive reflected light at the corresponding light receiving timings.

13. The distance measuring device according to claim 12, wherein the plurality of light emission timings include a plurality of types of light emission timings in which the number of light-emitting light-emitting groups differs from each other.

Images