Light emitting device and distance measuring system

Abstract

In the present disclosure, a light emitting device and a ranging system capable of further increasing security are provided. According to the present disclosure, provided is a light-emitting device comprising: a laser light source; a lens that expands the light beam emitted from the laser light source with respect to an optical axis; and a diffusion plate that more uniformizes the intensity distribution of the light beam incident from the lens and emits a light beam expanded with respect to the optical axis.

Description

Technical Field

[0001] This disclosure relates to light-emitting devices and ranging systems. Background Technology

[0002] Distance measurement systems based on Time of Flight (ToF) are generally known to measure the distance to an object. TOF systems typically include direct TOF (dTOF) and indirect TOF (iTOF). Direct TOF uses a lens to emit laser light from a laser source as pulses, and a photodetector called a SPAD (Single Photon Avalanche Diode) is used to detect photons reflected from the object illuminated by each pulse.

[0003] Avalanche multiplication is a technique that uses avalanche multiplication to convert the resulting charge carriers into electrical signal pulses, which are then input into a TDC (Time to Digital Converter) to measure the arrival time of the reflected light and calculate the distance to the object. On the other hand, indirect Time-of-Flight (ToF) emits pulsed light from a light-receiving element and uses a semiconductor element structure that detects the charge generated by the reflected light from the object and whose accumulation varies with the arrival time of the light to measure the time of flight of the light.

[0004] Furthermore, regarding the use of laser light sources, safety standards have been established from the perspective of safety for the human body and eyes. In order to avoid any impact on the human body, the laser class of the light projected from the ranging system is required to be set to safety benchmark level 1.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2022-96620 Summary of the Invention

[0008] The technical problem that the invention aims to solve

[0009] However, when the emitting surface of a laser light source is small, the image of the light source formed on the retina of the eye also becomes small, which can easily cause damage to the eyes. In addition, if there is unevenness on the emitting surface, it will create areas of strong laser intensity and areas of weak laser intensity, and the irradiation of the strong area is more likely to cause damage to the eyes.

[0010] Therefore, this disclosure provides a light-emitting device and a ranging system that can further increase security.

[0011] Technical solutions for solving technical problems

[0012] To solve the above-mentioned technical problems, according to this disclosure, a light-emitting device is provided, comprising: a laser source; a lens for expanding a light beam emitted from the laser source relative to an optical axis; and a diffuser for making the intensity distribution of the light beam incident from the lens more uniform and emitting a light beam expanded relative to the optical axis.

[0013] Alternatively, it may include: a laser source; a diffuser plate that makes the intensity distribution of the beam incident from the laser source more uniform and expands it relative to the optical axis; and a lens that expands the beam emitted from the diffuser plate relative to the optical axis.

[0014] Alternatively, the output of the laser source can be controlled in such a way that the laser power of the beam emitted from the laser source at a position 100 mm from the diffuser plate, on a plane orthogonal to the optical axis, is below a predetermined value.

[0015] Alternatively, the beam emitted from the diffuser plate may be configured such that, in the absence of the diffuser plate, the first expansion angle of the beam emitted from the lens is less than twice the second expansion angle of the beam emitted from the lens.

[0016] Alternatively, the spacing between the diffuser plates may be less than 1 millimeter.

[0017] Alternatively, the diffuser plate can be a lens array.

[0018] Alternatively, the spacing between the diffuser plates can be greater than 1 mm and less than 10 mm.

[0019] Alternatively, the laser source may consist of multiple laser light-emitting elements arranged in a two-dimensional shape on the light-emitting surface.

[0020] The direction of the beam emitted from the diffuser plate is changed at the light-emitting positions of the plurality of laser light-emitting elements.

[0021] Alternatively, it may also include a shielding plate, which has an opening at the emission end, through which the optical axis passes.

[0022] Alternatively, the emission of multiple laser light-emitting elements can be controlled in such a way that the light beam passes through the entire range of the opening.

[0023] Alternatively, the width of the light beam passing through the shielding plate can be set as Y, the distance along the optical axis from the exit surface of the shielding plate to the opening can be set as L10, and the maximum angle of the direction of the light beam emitted from the diffuser plate relative to the optical axis can be set as... When the length of the opening in the direction orthogonal to the optical axis is set as X, it has The relationship.

[0024] Alternatively, the output of the laser source can be controlled in such a way that the laser power of the beam emitted from the opening is below a predetermined value.

[0025] To solve the aforementioned technical problems, according to this disclosure, a ranging system is provided, comprising: a light-emitting device; an overall control unit for controlling the light-emitting device; and a ranging device for receiving reflected light from a light beam emitted by the light-emitting device, wherein the light-emitting device has: a laser source; a lens for expanding the light beam emitted from the laser source relative to the optical axis; and a diffuser for making the intensity distribution of the light beam incident from the lens more uniform and emitting the light beam expanded relative to the optical axis. Attached Figure Description

[0026] Figure 1 This is a block diagram illustrating an example of the structure of a ranging system in one embodiment of the present technology.

[0027] Figure 2 It is a diagram showing the general structure of an optical system.

[0028] Figure 3 This is a diagram illustrating an example of a flash-type optical system.

[0029] Figure 4 This is a diagram showing a detailed structural example of an optical device.

[0030] Figure 5 This is a diagram showing an example of the structure of a light-emitting device.

[0031] Figure 6 This is a diagram that schematically overlaps the light beam involved in this embodiment and the light beam involved in the comparative example.

[0032] Figure 7 It is a graph showing the relationship between the expansion angle and intensity relative to the optical axis.

[0033] Figure 8 This is a diagram showing a detailed structural example of other light-emitting devices involved in this embodiment.

[0034] Figure 9 This is a diagram showing a structural example of the light-emitting device according to the second embodiment.

[0035] Figure 10 This is a diagram showing an example of the arrangement of laser light-emitting elements on the light-emitting surface of a laser light source.

[0036] Figure 11 This is a block diagram illustrating an example of the general structure of a vehicle control system.

[0037] Figure 12 This is an explanatory diagram showing an example of the location of the vehicle's external information detection unit and camera unit. Detailed Implementation

[0038] Hereinafter, embodiments of the light-emitting device and the ranging system will be described with reference to the accompanying drawings. The description will focus on the main components of the light-emitting device and the ranging system; however, there may be components and functions not shown or described in the light-emitting device and the ranging system. The following description does not exclude components and functions not shown or described.

[0039] (First Implementation)

[0040] Figure 1 This is a block diagram illustrating an example of the schematic structure of the ranging system 1 according to an embodiment of this disclosure. For example... Figure 1 As shown, the ranging system 1 includes a light-emitting device 10, a ranging device 20, an overall control unit 30, and a light-receiving optical system 40. The ranging system 1 is a sensor system equipped with a light source and a ToF sensor, configured to emit light and detect reflected light reflected by the object 50. Here, the object 50 can be one or more objects present within the field of view of the ranging system 1.

[0041] The light-emitting device 10 is configured to emit a laser (irradiation light) L0 toward the object 50 based on instructions from the overall control unit 30. Based on instructions from the overall control unit 30, the light-emitting device 10 emits the laser L0 at a predetermined emission cycle by alternating between emitting light and not emitting light. Details of the light-emitting device 10 will be described below.

[0042] The light-receiving optical system 40 is configured to include a lens that forms an image on the light-receiving surface of the ranging device 20. A light pulse (reflected light pulse L1) emitted from the light-emitting device 10 and reflected by the object 50 is incident on the light-receiving optical system 40.

[0043] like Figure 1 As shown, the ranging device 20 includes a pixel array 100, a ranging processing unit 110, a ranging control unit 120, a driving circuit 130, a light emission timing control unit 140, a control unit 150, a clock generation unit 160, and an output unit 170. The ranging device 20 is configured to detect a reflected light pulse L1 based on an instruction from the overall control unit 30. Then, the ranging device 20 generates a distance image based on the detection result and outputs the image data of the generated distance image as distance information D1 from the output unit 170.

[0044] The pixel array 100, ranging processing unit 110, ranging control unit 120, driving circuit 130, emission timing control unit 140, control unit 150, clock generation unit 160, and output unit 170 can be configured on a single semiconductor chip. Alternatively, the ranging device 20 can also be a structure in which a first semiconductor chip and a second semiconductor chip are stacked. In this case, for example, consider a structure in which a portion of the pixel array 100 (photoelectric conversion unit 1001) is configured on the first semiconductor chip, and other parts of the ranging device are configured on the second semiconductor chip.

[0045] exist Figure 1 In this system, the overall control unit 30 controls the operation of the ranging system 1 as a whole according to a pre-loaded program. Additionally, the overall control unit 30 can perform control based on external control signals supplied from the outside. On the other hand, the control unit 150 controls the operation of the ranging device 20 as a whole according to instructions from the overall control unit 30.

[0046] The clock generation unit 160 generates one or more clock signals for use within the ranging device 20 based on a reference clock signal supplied from an external source. The illumination timing control unit 140 generates an illumination control signal indicating the illumination timing based on an illumination trigger signal supplied from the overall control unit 30. The illumination control signal is supplied to the illumination device 10 and also to the ranging processing unit 110. The ranging control unit 120 controls the operation of the ranging processing unit 110 based on an instruction from the control unit 150, thereby causing the ranging processing unit 110 to generate distance information based on detection signals output from each pixel 1000 of the pixel array 100.

[0047] The pixel array 100 includes a plurality of pixels 1000 configured in a matrix. Each pixel 1000 is configured to generate a detection signal PLS corresponding to the amount of light detected by detecting light. In this embodiment, all or a portion of the pixel array 100 is used to detect the reflected light L1. The area used in the pixel array 100 can be a rectangle that is the same as the image of the reflected light L1 imaged on the pixel array 100 when the laser L0 is reflected as a whole as the reflected light L1, and is long in the direction perpendicular to the scanning direction (the vertical direction in the figures, also referred to as the vertical direction below). However, it is not limited to this; various deformations, such as areas larger or smaller than the image of the reflected light L1 imaged on the pixel array 100, are also possible.

[0048] The driving circuit 130 includes a shift register and an address decoder, etc., to drive each pixel 1000 of the pixel array 100 simultaneously, column by column. Therefore, the driving circuit 130 includes at least: circuitry for applying the quenching voltage V_QCH (described later) to each pixel 1000 in a selected column within the pixel array 100; and circuitry for applying the selection control voltage V_SEL (described later) to each pixel 1000 in the selected column. Then, the driving circuit 130 selects the pixel 1000 for detecting photon incidence in column by applying the selection control voltage V_SEL to the pixel driving line LD corresponding to the column to be read out.

[0049] The detection signal output from the pixel array 100 is supplied to the ranging processor 110. The ranging processor 110 includes a TDC unit 111, a histogram generation unit 112, and a signal processing unit 113.

[0050] The detection signal PLS read from each pixel 1000 is supplied to the TDC unit 111. Here, the detection signal is read out for, for example, each pixel column in the pixel array 100 at a predetermined sampling period, and the detection signal is supplied to the TDC unit 111.

[0051] The TDC unit 111 measures the time difference from a reference moment (e.g., the moment when the light emission control signal is input from the light emission timing control unit 140) to the input of the detection signal PLS supplied from the pixel array 100, and generates digital information representing the measured time difference. That is, the TDC unit 111 generates time information based on the light emission control signal and the detection signal PLS, which represents the flight time from when light is emitted from the light source unit 10 and reflected by the object 50 to when it reaches each pixel 1000.

[0052] The histogram generation unit 112 generates a histogram based on the time information generated by the TDC unit 111. Here, the histogram generation unit 112 counts the time information based on a unit time d set by the ranging control unit 120, and generates the histogram. The unit time d can, for example, be the time width allocated to one bar (bin) in the histogram. Alternatively, the unit time d can also be, for example, the same time width as the sampling period for reading the detection signal from each pixel 1000 of the pixel array 100.

[0053] The signal processing unit 113 performs prescribed calculations based on the histogram data generated by the histogram generation unit, such as calculating distance information. For example, the signal processing unit 113 generates a curve approximation of the histogram based on the histogram data. The signal processing unit 113 detects the peak value of the curve of the histogram approximation, and based on the detected peak value, can calculate the distance D to the object 50.

[0054] The distance information output from the ranging processing unit 110 is supplied to the output unit 170. The output unit 170, also known as the interface unit, outputs the distance information provided by the ranging processing unit as output data to the outside. As the output unit 170, for example, MIPI (Mobile Industry Processor Interface) can be used.

[0055] The overall control unit 30 is configured to supply control signals to the light-emitting device 10 and the ranging device 20, and control the operation of the ranging system 1 by controlling their operation.

[0056] [Optical System]

[0057] Figure 2 This is a diagram showing a schematic structure of the optical system of the ranging system 1 according to this embodiment. Figure 2 The example illustrates a so-called scanning optical system that scans the field of view of the rangefinder 20 in the horizontal direction.

[0058] like Figure 2 As shown, the ranging system 1, as an optical system, includes a light source 11, a lens 12, a semi-reflecting mirror 13, a multi-faceted mirror 14, a light-receiving lens 15, and a pixel array 100. The light source 11, lens 12, semi-reflecting mirror 13, and multi-faceted mirror 14 are, for example, included in... Figure 1 The light-emitting device 10 is included in the light-emitting device. Additionally, the light-receiving lens 15 is included. Figure 1 In the light-receiving optical system 40, it should be noted that the semi-reflective mirror 13 and the multi-faceted mirror 14 can also be shared by the light source unit 10 and the light-receiving optical system 40.

[0059] exist Figure 2 In the structure shown, the laser L0 emitted from the light source 11 is converted by the lens 12 into a rectangular parallel beam B10 with a vertically elongated intensity spectrum, and then incident on the semi-reflecting mirror 13. The semi-reflecting mirror 13 reflects a portion of the incident laser L0. The laser L0 reflected by the semi-reflecting mirror 13 is then incident on the polygonal mirror 14. The polygonal mirror 14, for example, is vibrated horizontally about a predetermined rotation axis by a drive unit 16 that operates based on control from the overall control unit 30. As a result, the laser L0 is horizontally scanned, such that the field of view SR of the laser L0 reflected by the polygonal mirror 14 reciprocates horizontally within the ranging range AR. It should be noted that the drive unit 16 can use MEMS (Micro-Electro-Mechanical System) and micro-motors, etc.

[0060] Laser L0 reflected by the multifaceted mirror 14 is reflected by an object 50 existing within the ranging range AR, and incident on the multifaceted mirror 14 as reflected light L1. A portion of the reflected light L1 incident on the multifaceted mirror 14 passes through the semi-reflective mirror 13 and is incident on the light-receiving lens 15, thereby imaging a specific area in the pixel array 100. It should be noted that the specific area can be the entire pixel array 100 or a portion thereof. In addition, the specific area can be, for example, the area corresponding to the first area in the claims.

[0061] Figure 3 This is a diagram illustrating an example of a flash-type optical system. Figure 2 The example shown is a scanning optical system, but it is not limited to this; for example, such as... Figure 3 As shown, it can also be a so-called flash-type optical system where the field of view of the ranging system 1 is fixed. In this case, as... Figure 3 As shown, the system includes a light source 11, a lens 12, a condenser lens 18, and a pixel array 100. Laser light emitted from the light source 11 is converted by the lens 12 into a beam B10 with a sufficiently wide extension angle, illuminating the entire ranging range AR. Laser light L0 reflected by an object 50 within the ranging range AR is reflected as light L1 and incident on the pixel array 100 via the condenser lens 18. Thus, in the flash-type ranging system 1, which can measure the entire ranging range AR with a single emission, the drive unit 16, the semi-reflector 13, and the multi-faceted reflector 14 for scanning within the ranging range AR are unnecessary. Therefore, compared to the scanning-type ranging system 1, it has the advantage of a smaller optical system.

[0062] [Light-emitting device]

[0063] Figure 4 This is a diagram showing a detailed structural example of the light-emitting device 10 according to this embodiment. (See diagram for details.) Figure 4 As shown, the light-emitting device 10 according to this embodiment includes a laser light source 11, a lens 12, and a diffuser plate 19. Figure 4 The diagram further illustrates the optical axis Op10, the beam B10, and the laser power measurement surfaces M10a and b. It should be noted that the laser power measurement surfaces M10a and b are related to safety standards; details will be provided below.

[0064] The laser source 11, as a surface light source, can be, for example, a VCSEL (Vertical Cavity Surface Emitting Laser). The laser source 11 is not limited to a VCSEL; it can also be a semiconductor-excited solid-state laser, etc. The optical axis Op10 is orthogonal to the emitting surface of the laser source 11 and passes through the center of the laser source 11.

[0065] Lens 12 is, for example, a combination of multiple lenses. For instance, lens 12 serves to expand the laser beam emitted from laser source 11 relative to the optical axis Op10. Thus, the emitted light from laser source 11 is uniformly expanded by lens 12 and projected onto diffuser plate 19. This expands the measurement range. Therefore, in the ranging system 1, lens 12 is typically configured to expand the field of illumination (FOI). It should be noted that the combination of multiple lenses can be arbitrary, including combinations of convex lenses, concave lenses, etc. Alternatively, lens 12 can also be composed of a single lens.

[0066] The diffuser 19 diffuses the light incident via the lens 12 in a uniform direction, for example. The diffuser 19 is, for example, a diffuser with a spacing dimension of less than 1 mm. The emitted light from the laser source 11, if it strikes the diffuser 19, is diffused at a certain expansion angle through the diffuser components with a spacing dimension of less than 1 mm. Thus, these lights overlap on the illumination surface of the diffuser, eliminating uneven illumination and resulting in a uniform beam B10 being emitted. In other words, the diffuser 19 makes the intensity distribution of the incident beam more uniform and facilitates its emission.

[0067] Alternatively, the diffuser plate 19 can also be a so-called lens array with a spacing size on the order of several millimeters. For example, the spacing size of the diffuser plate 19 is 1 millimeter or more but less than 10 millimeters. The spacing size can be selected according to the object being measured and the measurement distance.

[0068] Figure 5 This diagram shows a structural example of the light-emitting device 10a as a comparative example. The light-emitting device 10a is an example of a conventional light-emitting device. That is, the light-emitting device 10a as a comparative example is a structure in which the diffuser plate 19 is removed from the light-emitting device 10 according to this embodiment. The lens 12 serves to expand the laser beam emitted by the laser source 11 relative to the optical axis Op10, and is emitted as beam B10a.

[0069] Figure 6 This is a schematic diagram showing the light beam B10 of the light-emitting device 10 according to this embodiment and the light beam B10a of the light-emitting device 10a according to the comparative example, with the two beams overlapping. Figure 6 The diagram further illustrates position P10.

[0070] Figure 7 It means Figure 6 A graph showing the relationship between the expansion angle and intensity of beams B10 and B10a at position P10 relative to the optical axis Op10. The horizontal axis represents the expansion angle, and the vertical axis represents the intensity. The expansion angle of 0 degrees corresponds to the optical axis Op10. The expansion angle is Y when only lens 12 is used, and X when both lens 12 and diffuser 19 are used.

[0071] like Figure 7 As shown, the beam B10 of the light-emitting device 10 according to this embodiment, passing through the diffuser plate 19, has a larger expansion angle at the same position P10 than that of the light-emitting device 10a according to the comparative example. That is, assuming a person views the laser source 11 side of the light-emitting device 10 from the optical axis side, the range of the beam B10 illuminating the retina of the eye is wider than that of the beam B10a. Therefore, compared with the light-emitting device 10a according to the comparative example, the light-emitting device 10 according to this embodiment can increase the upper limit of the laser output of the laser source 11 that will not cause damage to the eyes.

[0072] The diffuser plate 19 can have an expansion angle, for example, within the range of 0.5° to 80°. On the other hand, to achieve the desired field of illumination (FOI), if the expansion angle in the diffuser plate 19 is further expanded, a corresponding light-receiving lens design is required, potentially leading to increased costs and larger lenses. Therefore, in this embodiment, as... Figure 7 As shown, the contribution of the diffuser plate 19 to the expansion angle is limited to the range where Y ≥ X / 2. This helps to suppress cost increases and lens enlargement. Specifically, when Y is set as the first expansion angle and X as the second expansion angle, the first expansion angle is configured to be less than twice the second expansion angle.

[0073] Here, refer again Figure 4 , Figure 5 The laser power measurement surfaces M10 and M10a of safety standard level 1 will be explained. In safety standard level 1, the laser level is determined based on the measured laser power on the measurement surface located at a distance of 100 mm or more from the emitting surface of the laser source. On the other hand, in the case of an optical system with a diffuser plate, in safety standard level 1, the laser level is determined based on the measured laser power on the measurement surface located at a distance of 100 mm or more from the irradiation surface of the diffuser plate.

[0074] Under such conditions, the light-emitting device 10 according to this embodiment, since it uses a diffuser plate 19, is equivalent to an optical system having a diffuser plate 19. In this case, as... Figure 4 As shown, the laser level is determined based on the measured value of the laser power on the laser power measuring surface M10, which is at a distance of L10 (100 mm or more) from the irradiation surface of the diffuser plate 19.

[0075] On the other hand, in the light-emitting device 10a involved in the comparative example, if the following requirements are met, such as Figure 4 , 5As shown, the laser class is determined based on the measured laser power on the laser power measuring surface M10a, which is at a distance L10 (100 mm or more) from the emitting surface of the laser source 11. Therefore, in the light-emitting device 10 according to this embodiment, by moving the laser power measuring surface M10 further away from the emitting surface of the laser source 11, the light intensity is reduced, and a laser class 1 determination can be easily obtained. In other words, the output of the laser source 11 can be further increased within the safety standard class 1 range.

[0076] Figure 8 This is a diagram showing a detailed structural example of another light-emitting device 10b involved in this embodiment. For example... Figure 8 As shown, the light-emitting device 10b according to this embodiment includes a laser light source 11, a diffuser plate 19, and a lens 12. Figure 4 The difference in the light-emitting device 10a shown is that the diffuser plate 19 is disposed between the laser light source 11 and the lens 12.

[0077] The diffuser plate 19 is configured to be closer to the incident end of the lens 12 than the emission surface of the laser light source 11. If the diffuser plate 19 is close to the emission surface of the laser light source 11, it becomes the lens 12 as the light expanded by the diffuser plate 19 is further expanded, and the lens 12 becomes larger. In contrast, in this embodiment, since the diffuser plate 19 is configured to be closer to the incident end of the lens 12 than the emission surface of the laser light source 11, the large size of the lens 12 is suppressed.

[0078] Furthermore, in the case of the light-emitting device 10b according to this embodiment, the laser category is determined based on the measured value of the laser power on the laser power measuring surface M10b, which is at a distance L10 (100 mm or more) from the irradiation surface of the diffuser plate 19. Therefore, in the light-emitting device 10b according to this embodiment, by moving the laser power measuring surface M10b away from the LD emitting position, the light intensity is reduced, and the laser class 1 determination can be easily obtained. In other words, the output of the laser source 11 can be further increased within the safety standard class 1 range.

[0079] As explained above, in the ranging system 1 of this embodiment, the light-emitting device 10 uses a lens 12 and a diffuser plate 19 to illuminate the laser source 11. By using the diffuser plate 19, the intensity distribution of the light beam B10 illuminated by the light-emitting device 10 can be made more uniform, and the light beam B10 can be further extended relative to the optical axis Op10. As a result, safety can be increased, and the output of the laser source 11 can be further improved within the safety benchmark level 1.

[0080] (Second Implementation)

[0081] The difference between the ranging system 1 according to the second embodiment and the ranging system 1 according to the first embodiment is that the laser light source 11 in the light-emitting device 10c is expanded by the lens 12 and the diffuser 19, so that the light beam can pass through the opening of the aperture even if the light-emitting position of the light-emitting element of the laser light source 11 is changed. Hereinafter, the differences from the ranging system 1 according to the first embodiment will be explained.

[0082] Figure 9 This is a diagram illustrating a structural example of the light-emitting device 10c according to the second embodiment. Figure 9 In the diagram, the optical axis Op10 is oriented along the Z-axis, while the X-axis and Y-axis are orthogonal to the Z-axis. Figure 9 (a) indicates that the light beam is relative to the optical axis Op10. A diagram showing an example of illumination directed towards the X-axis at an angle of degrees. Figure 9 (b) is a diagram showing an example of a beam illuminating the optical axis Op10.

[0083] like Figure 9 As shown, the light-emitting device 10c includes a laser light source 11, a lens 12, a diffuser 19, and a shielding plate sh10. The shielding plate sh10 is disposed at the end of the light-emitting device 10c on the emission side. The opening Ap10 of the shielding plate sh10 is, for example, a square with one side measuring X millimeters. For example, X is 7 millimeters (mm). The optical axis Op10 passes through the center of the opening Ap10.

[0084] Figure 10 This diagram shows an example of the arrangement of laser light-emitting elements S11 disposed on the light-emitting surface of the laser light source 11. Figure 10 In (a), the optical axis Op10 passes through the center of the emitting surface in a manner orthogonal to the emitting surface. Multiple laser emitting elements S11 are arranged in a two-dimensional lattice pattern on the emitting surface. These multiple laser emitting elements S11 are controlled by an overall control unit 30 (see reference 30). Figure 1 The light emission is controlled by the overall control unit 30. The emission positions of the multiple laser light-emitting elements S11 are controlled, thereby changing the direction of the light beam emitted from the opening Ap10 relative to the optical axis Op10. The maximum angle between the direction of the light beam emitted from the end of the laser light-emitting element S11 and emitted from the opening Ap10 and the optical axis Op10 is set as...

[0085] Refer again Figure 9 The width W10 of the beam B10, which is extended by the lens 12 and the diffuser 19, when passing through the diffuser 19 is set to Y millimeters (mm). The length of the opening Ap10 from the emission surface of the diffuser 19 is set to L10 millimeters (mm). At this time, it is configured in a manner with the relationship of equation (1).

[0086] [Mathematical Expression 1]

[0087] Y / 2>L10×tan(φ)+X / 2 (1)

[0088] For example, when L10 is 100 mm, the laser power measurement surface in safety standard level 1 is the opening Ap10. Figure 9 As shown, when the optical system has the relationship of Equation (1), even if the overall control unit 30 or the laser source 11 fails, the laser emitting element S11 of the optical axis of the emitting surface of the laser source 11 continues to emit light, and the amount of light entering the opening Ap10 is the same under normal conditions and under failure conditions. Therefore, the degree of danger does not change even under failure conditions, and the output of the laser source 11 can be maintained within the safety standard level 1.

[0089] As explained above, in the second embodiment, a shielding plate sh10 with an opening Ap10 is disposed at the end of the emission side of the light-emitting device 10c. Then, as shown in equation (1), an optical system is configured such that the light beam B10 extended by the lens 12 and the diffuser plate 19 always passes through the opening Ap10, and the laser emitting element S11 is controlled. As a result, the amount of light passing through the opening Ap10 is a fixed value regardless of the direction of the light beam emitted from the opening Ap10. Therefore, even if the overall control unit 30 or the laser light source 11 fails, the laser emitting element S11 of the optical axis of the light-emitting surface of the laser light source 11 continues to emit light, and the amount of light entering the opening Ap10 will not be greater than usual even in the event of a failure. In particular, if the distance between the emission surface of the diffuser plate 19 and the opening Ap10 is set to 100 mm, the output of the laser light source 11 can be maintained within the safety reference level 1 even in the event of a failure.

[0090] <<Application Examples>>

[0091] The technology disclosed herein can be applied to a variety of products. For example, the technology disclosed herein can be implemented as a component in any type of mobile body, such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility devices, airplanes, drones, ships, robots, construction machinery, and agricultural machinery (tractors).

[0092] Figure 11 This is a block diagram illustrating a schematic structural example of a vehicle control system 7000, which is an example of a mobile body control system capable of applying the technologies disclosed herein. The vehicle control system 7000 includes multiple electronic control units connected via a communication network 7010. Figure 11In the example shown, the vehicle control system 7000 includes 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 multiple control units can be, for example, an in-vehicle communication network based on any standard such as CAN (Controller Area Network), LIN (Local Interconnect Network), LAN (Local Area Network), or FlexRay (registered trademark).

[0093] Each control unit includes: a microcomputer for performing calculations according to various programs; a storage unit for storing programs executed by the microcomputer or parameters used in various calculations; and a drive circuit for driving various controlled objects. Each control unit has a network I / F for communication with other control units via the communication network 7010, and a communication I / F for communication between components or sensors inside and outside the vehicle via wired or wireless communication. Figure 11 The diagram illustrates the functional structure of the integrated control unit 7600, including a microcomputer 7610, a general communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiver 7650, an in-vehicle equipment I / F 7660, an audio / image output unit 7670, an in-vehicle network I / F 7680, and a storage unit 7690. Other control units also similarly include a microcomputer, communication I / F, and storage unit.

[0094] The drive system control unit 7100 controls the operation of parts associated with the vehicle's drive system according to various programs. For example, the drive system control unit 7100 functions as a drive force generating unit (such as an internal combustion engine or drive motor) for generating drive force for the vehicle, a drive force transmission mechanism for transmitting drive force to the wheels, a steering mechanism for adjusting the vehicle's steering angle, and a braking unit for generating braking force for the vehicle. The drive system control unit 7100 may also function as a control unit for ABS (Anti-lock Braking System) or ESC (Electronic Stability Control).

[0095] A vehicle status detection unit 7110 is connected to the drive system control unit 7100. The vehicle status detection unit 7110 includes, for example, at least one of the following sensors: a gyroscope sensor for detecting the angular velocity of the vehicle body's axis rotation, an acceleration sensor for detecting the vehicle's acceleration, or 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, engine speed, or wheel speed. The drive system control unit 7100 performs calculations using signals input from the vehicle status detection unit 7110 to control the internal combustion engine, drive motor, electric power steering unit, or braking unit, etc.

[0096] The vehicle body system control unit 7200 controls the operation of various parts equipped on the vehicle body according to various programs. For example, the vehicle body system control unit 7200 functions as a control unit for keyless entry systems, smart key systems, power windows, or various lights such as headlights, reversing lights, brake lights, turn signals, or fog lights. In this case, radio waves or signals from a portable device that replaces the key can be input to the vehicle body system control unit 7200. The vehicle body system control unit 7200 receives these radio waves or signal inputs and controls the vehicle's door locks, power windows, lights, etc.

[0097] The battery control unit 7300 controls the secondary battery 7310, which serves as the power supply for the drive motor, according to various programs. For example, information such as battery temperature, battery output voltage, or remaining battery capacity is input from the battery compartment containing the secondary battery 7310 to the battery control unit 7300. The battery control unit 7300 uses these signals for calculation and processing to perform temperature regulation control of the secondary battery 7310 or control of the cooling unit, etc., provided by the battery compartment.

[0098] The exterior information detection unit 7400 detects external information of the vehicle equipped with the vehicle control system 7000. For example, at least one of a camera unit 7410 and an exterior information detection unit 7420 is connected to the exterior information detection unit 7400. The camera unit 7410 includes at least one of a ToF (Time of Flight) camera, a stereo camera, a single-lens reflex camera, an infrared camera, and other cameras. The exterior information detection unit 7420 includes, for example, an environmental sensor for detecting current weather or meteorological conditions, or at least one of a surrounding information detection sensor for detecting other vehicles, obstacles, or pedestrians around the vehicle equipped with the vehicle control system 7000.

[0099] Environmental sensors may be, for example, at least one of a raindrop sensor for detecting rain, a fog sensor for detecting fog, a sunlight sensor for detecting sunlight intensity, and a snow sensor for detecting snowfall. Ambient information detection sensors may be at least one of an ultrasonic sensor, a radar unit, and a LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) unit. These camera units 7410 and external information detection units 7420 may be provided as separate, independent sensors or components, or as a component integrating multiple sensors or components.

[0100] Here, Figure 12 Examples of the installation positions of the camera unit 7410 and the vehicle exterior information detection unit 7420 are shown. Camera units 7910, 7912, 7914, 7916, and 7918 are installed, for example, at at least one location among the front nose, side mirrors, rear bumper, rear door, and the upper part of the windshield inside the vehicle 7900. The camera unit 7910 in the front nose and the camera unit 7918 in the upper part of the windshield inside the vehicle primarily acquire images of the front of the vehicle 7900. The cameras 7912 and 7914 in the side mirrors primarily acquire images of the sides of the vehicle 7900. The camera unit 7916 in the rear bumper or rear door primarily acquires images of the rear of the vehicle 7900. The camera unit 7918 in the upper part of the windshield inside the vehicle is mainly used for detecting vehicles, pedestrians, obstacles, traffic lights, traffic signs, or lanes ahead.

[0101] It should be noted that, in Figure 12 The diagram illustrates an example of the shooting range of each of the cameras 7910, 7912, 7914, and 7916. Shooting range a represents the shooting range of the camera 7910 located at the front nose; shooting ranges b and c represent the shooting ranges of the cameras 7912 and 7914 located at the side rearview mirrors, respectively; and shooting range d represents the shooting range of the camera 7916 located at the rear bumper or rear door. For example, by overlapping the image data captured by the cameras 7910, 7912, 7914, and 7916, a top-down view of the vehicle 7900 can be obtained.

[0102] External information detection units 7920, 7922, 7924, 7926, 7928, and 7930, located at the front, rear, sides, corners, and above the windshield inside the vehicle 7900, can be, for example, ultrasonic sensors or radar units. External information detection units 7920, 7926, and 7930, located at the front nose, rear bumper, rear door, and above the windshield inside the vehicle 7900, can be, for example, LIDAR units. These external information detection units 7920 to 7930 are mainly used for detecting vehicles, pedestrians, or obstacles ahead.

[0103] Return to Figure 11 Continuing with the explanation, the exterior information detection unit 7400 causes the camera unit 7410 to capture images of the exterior of the vehicle and receives the captured image data. Additionally, the exterior information detection unit 7400 receives detection information from the connected exterior information detection unit 7420. If the exterior information detection unit 7420 is an ultrasonic sensor, radar unit, or LIDAR unit, the exterior information detection unit 7400 transmits ultrasonic waves or electromagnetic waves and receives information about the reflected waves. Based on the received information, the exterior information detection unit 7400 can also perform object detection processing such as detecting people, vehicles, obstacles, signs, or text on the road surface, or distance detection processing. Based on the received information, the exterior information detection unit 7400 can also perform environmental recognition processing such as identifying rain, fog, or road conditions. Based on the received information, the exterior information detection unit 7400 can also calculate the distance to objects outside the vehicle.

[0104] In addition, the vehicle exterior information detection unit 7400 can also perform image recognition processing or distance detection processing based on the received image data to identify people, vehicles, obstacles, signs, or text on the road surface. The vehicle exterior information detection unit 7400 can also perform distortion correction or position alignment processing on the received image data, and synthesize image data captured by different cameras 7410 to generate overhead or panoramic images. The vehicle exterior information detection unit 7400 can also use image data captured by different cameras 7410 to perform viewpoint switching processing.

[0105] The in-vehicle information detection unit 7500 detects information inside the vehicle. For example, a driver state detection unit 7510, which detects the driver's state, is connected to the in-vehicle information detection unit 7500. The driver state detection unit 7510 may include a camera for capturing images of the driver, a biosensor for detecting the driver's biological information, a microphone for collecting sound inside the vehicle, etc. The biosensor is installed, for example, on the seat surface or steering wheel, to detect the biological information of passengers sitting in the seat or drivers holding the steering wheel. The in-vehicle information detection unit 7500 can calculate the driver's fatigue level or concentration level based on the detection information input from the driver state detection unit 7510, and can also determine whether the driver is dozing off. The in-vehicle information detection unit 7500 can also perform noise cancellation and other processing on the collected sound signals.

[0106] The integrated control unit 7600 controls all operations within 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 can be implemented through components that allow passengers to input, such as touch panels, buttons, microphones, switches, or levers. Data obtained by voice recognition of sounds input through a microphone can also be input into the integrated control unit 7600. The input unit 7800 can be, for example, a remote control utilizing infrared or other radio waves, or an external connection device such as a mobile phone or PDA (Personal Digital Assistant) corresponding to the operation of the vehicle control system 7000. The input unit 7800 can also be, for example, a camera, in which case passengers can input information through gestures. Alternatively, data obtained by detecting the movement of a wearable device worn by the passenger can also be input. Furthermore, the input unit 7800 may also include, for example, an input control circuit that generates an input signal based on information input by passengers using the input unit 7800 and outputs it to the integrated control unit 7600. Passengers can input various data or instructions to the vehicle control system 7000 by operating the input unit 7800.

[0107] The storage unit 7690 may also 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. Alternatively, the storage unit 7690 may be implemented using magnetic storage devices such as HDDs (Hard Disc Drives), semiconductor storage devices, optical storage devices, or opto-magnetic storage devices.

[0108] The Universal Communication I / F 7620 is a general-purpose communication I / F that mediates communication between various devices existing in the external environment 7750. The Universal Communication I / F 7620 can employ cellular communication protocols such as GSM (Global System for Mobile Communications), WiMAX, LTE (Long Term Evolution), or LTE-A (LTE-Advanced), or other wireless communication protocols such as Wireless LAN (also known as Wi-Fi) or Bluetooth. The Universal Communication I / F 7620 can also connect, for example, via a base station or access point to devices (e.g., application servers or control servers) existing on external networks (e.g., the Internet, cloud networks, or operator-owned networks). Additionally, the Universal Communication I / F 7620 can also use P2P (Peer-to-Peer) technology to connect to terminals located near the vehicle (e.g., terminals of drivers, pedestrians, or shops, or MTC (Machine Type Communication) terminals).

[0109] The Dedicated Communication I / F 7630 is a communication I / F that supports communication protocols designed for use in vehicles. For example, the Dedicated Communication I / F 7630 can employ standard protocols such as WAVE (Wireless Access in Vehicle Environment), DSRC (Dedicated Short Range Communications), or cellular communication protocols, which combine IEEE 802.11p as the lower layer and IEEE 1609 as the upper layer. The Dedicated Communication I / F 7630 can, for example, implement one or more concepts including Vehicle-to-Vehicle (V2X) communication, Vehicle-to-Infrastructure (V2I) communication, Vehicle-to-Home (V2Home) communication, and Vehicle-to-Pedestrian (V2P) communication.

[0110] The positioning unit 7640 receives, for example, GNSS signals from GNSS (Global Navigation Satellite System) satellites (e.g., GPS signals from GPS (Global Positioning System) satellites) and performs positioning, generating location information including the vehicle's latitude, longitude, and altitude. It should be noted that the positioning unit 7640 can determine its current location by exchanging signals with a wireless access point, or it can obtain location information from a terminal with positioning capabilities, such as a mobile phone, PHS, or smartphone.

[0111] The beacon receiver 7650 receives, for example, radio waves or electromagnetic waves transmitted from a wireless station installed on the road, and obtains information such as current location, congestion, traffic closure, or estimated time. It should be noted that the functions of the beacon receiver 7650 can also be included in the aforementioned dedicated communication I / F 7630.

[0112] The in-vehicle device I / F 7660 is a communication interface that mediates the connection between the microcomputer 7610 and various in-vehicle devices 7760 present in the vehicle. The in-vehicle device I / F 7660 can also establish a wireless connection using wireless communication protocols such as Wireless LAN, Bluetooth, NFC (Near Field Communication), or WUSB (Wireless USB). Alternatively, the in-vehicle device I / F 7660 can also establish a wired connection via a connection terminal not shown (and a cable as required) such as USB (Universal Serial Bus), HDMI (High-Definition Multimedia Interface), or MHL (Mobile High-Definition Link). The in-vehicle device 7760 may include, for example, at least one of a mobile device or wearable device owned by a passenger, or an information device brought into or installed in the vehicle. Furthermore, the in-vehicle device 7760 may also include a navigation unit for exploring routes to any destination. The in-vehicle device I / F7660 exchanges control signals or data signals with these in-vehicle devices 7760.

[0113] The vehicle network I / F7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The vehicle network I / F7680 transmits and receives signals according to the specified protocols supported by the communication network 7010.

[0114] The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 according to various programs based on information obtained via at least one of the following: general communication I / F 7620, dedicated communication I / F 7630, positioning unit 7640, beacon receiving unit 7650, in-vehicle equipment I / F 7660, and in-vehicle network I / F 7680. For example, the microcomputer 7610 may also calculate control target values ​​for the drive force generation unit, steering mechanism, or braking unit based on the obtained information inside and outside the vehicle, and output control commands to the drive system control unit 7100. For example, the microcomputer 7610 may also perform coordinated control for the purpose of realizing the functions of ADAS (Advanced Driver Assistance System), such functions including collision avoidance or impact mitigation, following distance based on vehicle distance, speed maintenance, collision warning, or lane departure warning. In addition, the microcomputer 7610 can control the drive force generating unit, steering mechanism or braking unit, etc., based on the information obtained about the vehicle's surroundings, thereby performing coordinated control for the purpose of autonomous driving, such as driving autonomously without relying on the driver's operation.

[0115] The microcomputer 7610 can also generate three-dimensional distance information between the vehicle and surrounding structures and objects such as pedestrians based on information obtained via at least one of the following: general communication I / F 7620, dedicated communication I / F 7630, positioning unit 7640, beacon receiving unit 7650, in-vehicle equipment I / F 7660, and in-vehicle network I / F 7680. Furthermore, the microcomputer 7610 can predict dangers such as vehicle collisions, pedestrian approach, or entry into prohibited roads based on the obtained information, and can generate warning signals. Warning signals may include, for example, signals used to generate warning sounds or illuminate warning lights.

[0116] The audio-visual output unit 7670 sends an output signal of at least one of the audio and visual components to an output unit, which is capable of visually or audibly notifying passengers of the vehicle or those outside the vehicle of information. Figure 11In the example, an audio speaker 7710, a display unit 7720, and a dashboard 7730 are shown as output units. For example, the display unit 7720 may include at least one of an in-vehicle display and a head-up display. The display unit 7720 may also have AR (Augmented Reality) display functionality. The output unit may be other components besides these, such as headphones, wearable devices like glasses-type displays worn by passengers, projectors, or lamps. When the output unit is a display unit, the display unit visually displays the results of various processing performed by the microcomputer 7610 or information received from other control units in various forms such as text, images, tables, and charts. In addition, when the output unit is a sound output unit, the sound output unit converts audio signals composed of reproduced sound data or audio data into analog signals and outputs them in an audible manner.

[0117] It should be noted that, in Figure 11 In the example shown, at least two control units connected via the communication network 7010 can be integrated into a single control unit. Alternatively, each control unit can be composed of multiple control units. Furthermore, the vehicle control system 7000 may also include other control units not shown. Additionally, as described above, other control units can have some or all of the functions performed by any one control unit. That is, if information is transmitted and received via the communication network 7010, the prescribed computational processing can also be performed by any one control unit. Similarly, sensors or components connected to any one control unit can be connected to other control units, and multiple control units can mutually transmit and receive detection information via the communication network 7010.

[0118] It should be noted that this is used to achieve the desired usage. Figure 1 The computer programs for each function of the ranging system 1 described in this embodiment are installed in any control unit or the like. Alternatively, a computer-readable recording medium storing such a computer program can be provided. Examples of recording media include magnetic disks, optical disks, optical discs, and flash memory. Alternatively, the computer program described above can also be distributed, for example, via a network, without using a recording medium.

[0119] In the vehicle control system 7000 described above, the following is used: Figure 1 The ranging system 1 described in this embodiment can be applied to... Figure 11 The integrated control unit 7600 shown is an example of an application. For example, the ranging system 1 corresponds to the camera unit 7410.

[0120] It should be noted that this technology can adopt the following structure. (1)

[0122] A light-emitting device comprising:

[0123] Laser source;

[0124] A lens that expands the light beam emitted from the laser source relative to the optical axis; and

[0125] A diffuser plate makes the intensity distribution of the light beam incident from the lens more uniform and emits a light beam that extends relative to the optical axis. (2)

[0127] A light-emitting device comprising:

[0128] Laser source;

[0129] A diffuser plate that makes the intensity distribution of the beam incident from the laser source more uniform and extends it relative to the optical axis; and

[0130] A lens that expands the light beam emitted from the diffuser relative to the optical axis. (3)

[0132] According to the light-emitting device described in (1) or (2), the output of the laser light source is controlled in such a manner as follows: at a position 100 mm away from the diffuser plate, on a plane orthogonal to the optical axis, the laser power of the beam emitted from the laser light source is below a predetermined value. (4)

[0134] According to the light-emitting device described in (1), the first expansion angle of the light beam emitted from the diffuser plate is less than twice the second expansion angle of the light beam emitted from the lens when the diffuser plate is not present. (5)

[0136] According to the light-emitting device described in (3), the spacing dimension of the diffuser plate is less than 1 mm. (6)

[0138] According to the light-emitting device described in (3), the diffuser plate is a lens array. (7)

[0140] According to the light-emitting device described in (6), the spacing of the diffuser plate is more than 1 mm and less than 10 mm.

[0141] (8) The light-emitting device according to (1),

[0142] The laser source is composed of multiple laser light-emitting elements arranged in a two-dimensional shape on the light-emitting surface.

[0143] The direction of the beam emitted from the diffuser plate is changed at the light-emitting positions of the plurality of laser light-emitting elements. (9)

[0145] The light-emitting device according to (8) also includes a shielding plate having an opening at the emission end, through which the optical axis passes. (10)

[0147] According to the light-emitting device described in (9), the light emission of multiple laser light-emitting elements is controlled in such a way that the light beam passes through the entire range of the opening. (11)

[0149] According to the light-emitting device described in (10), when the width of the light beam passing through the shielding plate is set to Y, the distance along the optical axis from the emission surface of the shielding plate to the opening is set to L10, the maximum angle of the direction of the light beam emitted from the diffuser plate relative to the optical axis is set to φ, and the length of the opening in the direction orthogonal to the optical axis is set to X, it has the following characteristics: The relationship. (12)

[0151] According to the light-emitting device described in (11), the output of the laser light source is controlled in such a way that the laser power of the light beam emitted from the opening is below a predetermined value. (13)

[0153] A ranging system comprising:

[0154] Light-emitting device;

[0155] The overall control unit controls the light-emitting device; and

[0156] The ranging device receives the reflected light from the beam emitted by the light-emitting device.

[0157] The light-emitting device has:

[0158] Laser source;

[0159] A lens that expands the light beam emitted from the laser source relative to the optical axis; and

[0160] A diffuser plate makes the intensity distribution of the light beam incident from the lens more uniform and emits the light beam that extends relative to the optical axis.

[0161] This disclosure is not limited to the various embodiments described above, but also includes various modifications that can be conceived by those skilled in the art, and the effects of this disclosure are not limited to the above content. That is, various additions, changes, and partial deletions can be made without departing from the conceptual idea and spirit of this disclosure derived from the content defined in the claims and their equivalents.

[0162] Explanation of reference numerals in the attached figures

[0163] 1: Distance measuring system; 10, 10a, 10c: Light emitting device; 11: Laser light source; 12: Lens; 19: Diffuser plate; 20: Distance measuring device; 30: Overall control unit; Ap10: Opening; sh10: Shielding plate.

Claims

1. A light-emitting device, comprising: Laser source; A lens that expands the light beam emitted from the laser source relative to the optical axis; and A diffuser plate makes the intensity distribution of the light beam incident from the lens more uniform and emits a light beam that extends relative to the optical axis.

2. A light-emitting device, comprising: Laser source; A diffuser plate that makes the intensity distribution of the beam incident from the laser source more uniform and extends it relative to the optical axis; and A lens that expands the light beam emitted from the diffuser relative to the optical axis.

3. The light-emitting device according to claim 1, wherein, The output of the laser source is controlled in such a manner as described below: at a position 100 mm from the diffuser plate, on a plane orthogonal to the optical axis, the laser power of the beam emitted from the laser source is below a predetermined value.

4. The light-emitting device according to claim 1, wherein the device is configured as follows: The first expansion angle of the light beam emitted from the diffuser is less than twice the second expansion angle of the light beam emitted from the lens in the absence of the diffuser.

5. The light-emitting device according to claim 3, wherein, The spacing between the diffuser plates is less than 1 mm.

6. The light-emitting device according to claim 3, wherein, The diffuser plate is a lens array.

7. The light-emitting device according to claim 6, wherein, The spacing between the diffuser plates is greater than 1 mm and less than 10 mm.

8. The light-emitting device according to claim 1, wherein, The laser source is composed of multiple laser light-emitting elements arranged in a two-dimensional shape on the light-emitting surface. The direction of the beam emitted from the diffuser plate is changed at the light-emitting positions of the plurality of laser light-emitting elements.

9. The light-emitting device according to claim 8, wherein, The light-emitting device also includes a shielding plate, which has an opening at the emission end, and the optical axis passes through the center of the opening.

10. The light-emitting device according to claim 9, wherein, The emission of multiple laser light-emitting elements is controlled in such a way that the light beam passes through the entire range of the opening.

11. The light-emitting device according to claim 10, wherein, When the width of the light beam passing through the shielding plate is set as Y, the distance from the emission surface of the shielding plate to the opening along the optical axis is set as L10, the maximum angle of the direction of the light beam emitted from the diffuser plate relative to the optical axis is set as φ, and the length of the opening in the direction orthogonal to the optical axis is set as X, the relationship Y / 2>L10×tan(φ)+X / 2 is obtained.

12. The light-emitting device according to claim 11, wherein, The output of the laser source is controlled in such a way that the laser power of the beam emitted from the opening is below a predetermined value.

13. A ranging system, comprising: Light-emitting device; The overall control unit controls the light-emitting device; and The ranging device receives the reflected light from the beam emitted by the light-emitting device. The light-emitting device has: Laser source; A lens that expands the light beam emitted from the laser source relative to the optical axis; and A diffuser plate makes the intensity distribution of the light beam incident from the lens more uniform and emits the light beam that extends relative to the optical axis.

Images