Light-emitting device and range-measuring device

Abstract

Compared to a case where multiple light sources have the same illumination angle, this method suppresses the effect of misalignment of the light-emitting area on a single region. [Solution] This light-emitting device is characterized by arranging multiple light sources 410 to 440, each having multiple light-emitting sections that can emit light individually, driving each of the multiple light sources 410 to 440 so that only one light-emitting section A1 that irradiates light toward a single area is lit, and having an irradiation angle θ2 of some of the multiple light sources 440 that is larger than the irradiation angle θ1 of the other light sources 410 to 430.

Description

Technical Field

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

Background Art

[0002] For example, Patent Document 1 discloses a measuring device including a light-emitting unit including a first light-emitting section that emits light toward a first region and a second light-emitting section that emits light toward a second region different from the first region. This measuring device further includes a light-receiving unit including a first light-receiving section that receives light reflected in the first region and a second light-receiving section that receives light reflected in the second region. Further, this measuring device further includes an acquisition unit that acquires information regarding the second region from the result that the light emitted from the first light-emitting section is reflected in the second region and received by the second light-receiving section.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, there is a light-emitting device in which a plurality of light sources each having a plurality of light-emitting sections are arranged. Consider a case where a light-emitting section that irradiates light toward one region is in a lit state in each of the plurality of light sources. When the plurality of light sources have the same irradiation angle, it is assumed that the influence of the deviation of the light-emitting section with respect to one region becomes large due to the accuracy or the like when assembling the plurality of light sources. An object of the present invention is to suppress the influence of the deviation of the light-emitting section with respect to one region as compared with the case where the plurality of light sources have the same irradiation angle.

Means for Solving the Problems

[0005] The invention described in claim 1 is a light-emitting device characterized by arranging a plurality of light sources, each having a plurality of light-emitting compartments that can emit light individually, driving each of the plurality of light sources so that only one light-emitting compartment that irradiates light toward a certain area is lit, and having an irradiation angle of some of the plurality of light sources that is larger than the irradiation angle of the other light sources. The invention described in claim 2 is a light-emitting device according to claim 1, characterized in that the one light-emitting section in the partial light source irradiates over a region adjacent to the one region, and the range irradiated by the one light-emitting section in the partial light source is wider than the range irradiated by the one light-emitting section in the other light source. The invention described in claim 3 is a light-emitting device according to claim 2, characterized in that the one light-emitting section in the part of the light source irradiates light toward the entire area of ​​the one region and the adjacent region. The invention described in claim 4 is the light-emitting device according to claim 1, characterized in that the number of some light sources is smaller than the number of other light sources. The invention described in claim 5 is the light-emitting device according to claim 4, characterized in that the number of the partial light sources is one. The invention described in claim 6 is a light-emitting device according to claim 1, characterized in that the light source of the part comprises an optical member that makes the irradiation angle of the part of the light source larger than the irradiation angle of the other light source. The invention described in claim 7 is a light-emitting device according to claim 6, characterized in that the number of optical members is less than the number of the plurality of light-emitting compartments. The invention described in claim 8 is a distance measuring device comprising: a light-emitting device described in claim 1; a light-receiving unit that receives reflected light from the light-emitting device; an acquisition unit that acquires the result of light reception by the light-receiving unit; and a distance measuring unit that measures a distance based on the result of light reception acquired by the acquisition unit. [Effects of the Invention]

[0006] According to the invention of claim 1, it becomes possible to suppress the effect of misalignment of light-emitting sections on a single region compared to the case where multiple light sources have the same illumination angle. According to the invention of claim 2, one light-emitting section of some light sources illuminates an area adjacent to one area, and the range illuminated by one light-emitting section of some light sources is wider than the range illuminated by one light-emitting section of other light sources. Compared to a configuration in which such a configuration is not adopted, it becomes possible to suppress the effect of displacement of the light-emitting section on one area. According to the invention of claim 3, compared to a configuration in which one light-emitting section of a light source does not irradiate light toward the entire area of ​​one region and adjacent regions, it becomes possible to suppress the effect of misalignment of the light-emitting section toward one region. According to the invention of claim 4, the influence of highly reflective materials can be suppressed compared to not employing a configuration in which the number of some light sources is smaller than the number of other light sources. According to the invention of claim 5, it becomes possible to suppress the effects of the presence of highly reflective materials compared to a configuration in which only one light source is used. According to the invention of claim 6, some light sources can reduce costs compared to a configuration that does not employ an optical element that makes the illumination angle larger than that of other light sources. According to the invention of claim 7, the number of optical elements can reduce costs compared to a configuration in which the number of optical elements is less than the number of multiple light-emitting sections. According to the invention of claim 8, it becomes possible to suppress the effect of misalignment of light-emitting sections on a single region compared to the case where multiple light sources have the same illumination angle. [Brief explanation of the drawing]

[0007] [Figure 1] This block diagram shows an example of a schematic configuration of a distance measuring device to which this embodiment is applied. [Figure 2] This diagram illustrates the relationship between the light-emitting surface of the light-emitting unit according to this embodiment and the irradiation surface that is illuminated by the light emitted from the light-emitting unit. [Figure 3] This figure shows an example of a light-emitting unit according to this embodiment. [Figure 4] This diagram illustrates the relationship between the light-receiving surface and the illumination surface of the light-receiving unit according to this embodiment. [Figure 5] It is a diagram for explaining an example of the irradiation order of the irradiation sections on the irradiation surface. [Figure 6] It is a diagram for explaining the distance image in the present embodiment. (a) is a diagram showing the positional relationship between the distance measuring device and the object, (b) is a diagram showing an example of the distance image created by the control unit, and (c) is a diagram showing the state of the irradiation surface. [Figure 7] It is a perspective view showing a schematic configuration example of the distance measuring device to which the present embodiment is applied. [Figure 8] It is a diagram for explaining the configuration of the light source included in the light emitting unit. [Figure 9] It is a diagram for explaining a configuration example when an optical member is disposed on the light source. (a) and (b) show an example using a microlens as the optical member, and (c) and (d) show other examples using a lens as the optical member. [Figure 10] It is a diagram for explaining the light quantity distribution of the light receiving sections of the light receiving unit by the light of a plurality of light sources. [Figure 11] It is a graph for explaining an example. (a) and (b) show examples when the present embodiment is applied, and (c) shows a conventional example when the present embodiment is not applied for showing the difference from the example. [Figure 12] It is a graph for explaining a comparative example. (a) and (b) show the case where the irradiation angle of any of the light sources is θ2. [Figure 13] It is a diagram for explaining a modification example.

Mode for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the technical scope of the present invention is not limited to the scope described as embodiments below. It is clear from the description of the claims that combinations of a plurality of examples and those obtained by making various changes or improvements to these examples are also included in the technical scope of the present invention.

[0009] <Distance measuring device 1> (Overall configuration) FIG. 1 is a block diagram showing an example of the schematic configuration of a distance measuring device 1 to which the present embodiment is applied. The distance measuring device 1 measures the distance to an object based on the time from the timing when light is emitted from the light emitting unit 4 until the timing when the light reflected by the object is received by the light receiving unit 5. That is, the distance measuring device 1 is a device that measures distance based on the ToF method. The ToF method includes an indirect ToF (iToF: indirect ToF) method that measures time from the difference between the phase of the emitted light and the phase of the received light, and a direct ToF (dToF: direct ToF) method that directly measures the time from the emission to the reception of light. In the present embodiment, the distance measuring device 1 will be described as performing distance measurement based on the indirect ToF method.

[0010] As shown in FIG. 1, the distance measuring device 1 includes an optical device 3 and a control unit 8. The optical device 3 includes a light emitting unit 4 that emits light toward a predetermined irradiation range, a light receiving unit 5 that receives the light emitted from the light emitting unit 4 and reflected by an object existing in the irradiation range, a light emitting drive unit 6 that drives the light emitting unit 4, and a light receiving drive unit 7 that drives the light receiving unit 5. The configurations of the light emitting unit 4 and the light receiving unit 5 of the optical device 3 will be described in detail later. Also, the reference numeral 2 shown by the dashed line will be described later.

[0011] The control unit 8 controls the operations of the light emitting unit 4 and the light receiving unit 5 of the optical device 3. Further, the control unit 8 acquires the result of light reception in the light receiving unit 5, and based on this result of light reception, measures the distance from the distance measuring device 1 to the object by the ToF method.

[0012] The light receiving unit 5 detects infrared rays radiated from an object existing in the irradiation range (the irradiation surface 60 in FIG. 2 described later). The control unit 8 generates an infrared image from the detection result. The control unit 8 continuously or intermittently at a predetermined time interval detects the infrared rays in the irradiation range and generates an infrared image. The control unit 8 analyzes the acquired infrared images to understand the status of the object within the irradiation range. The control unit 8 determines whether the object is a moving object or a stationary object within the irradiation range. The control unit 8 also determines which irradiation section 61 (see Figure 2, described later) the object is located in within the irradiation range. Furthermore, if the object is a moving object, the control unit 8 determines the direction of movement of the object within the irradiation range and the relative amount of movement of the object within the irradiation range.

[0013] (Light-emitting part 4) Figure 2 illustrates the relationship between the light-emitting surface 40 of the light-emitting unit 4 according to this embodiment and the illumination surface 60 that is irradiated by the light emitted from the light-emitting unit 4. In Figure 2, the left direction of the paper is the +x direction, the top direction of the paper is the +y direction, and the back direction of the paper is the +z direction, with the opposite directions being -x, -y, and -z. In Figure 2, the light-emitting surface 40 and the illumination surface 60 are shown offset in the vertical direction (±y direction) of the paper, but in reality, the light-emitting surface 40 and the illumination surface 60 are arranged to face each other. In Figure 2, the light-emitting surface 40 of the light-emitting unit 4 is located in the front direction (-z direction) of the paper, and the illumination surface 60 is located in the back direction (+z direction) of the paper. In other words, Figure 2 shows the light-emitting unit 4 emitting light onto the illumination surface 60, viewed from the side opposite to the side from which the light-emitting unit 4 emits light. The light-emitting unit 4 is composed of, for example, one or more light-emitting chips.

[0014] The light-emitting unit 4 comprises a light-emitting surface 40 on which multiple vertical cavity surface-emitting lasers (VCSELs, indicated by reference numeral 43 in Figure 3, which will be described later) are arranged. The light-emitting unit 4 emits light toward the irradiation surface 60 through the emission of light from the VCSELs 43. In Figure 2, the VCSELs 43 are not shown. Furthermore, as will be described later, the light-emitting unit 4 may also be configured to have multiple light-emitting surfaces 40.

[0015] The light-emitting surface 40 is divided into multiple light-emitting compartments 41, each containing at least one VCSEL 43. Here, as an example, the light-emitting surface 40 is divided into a total of 12 light-emitting compartments 41, four in the x direction and three in the y direction. As shown in the figure, when it is necessary to distinguish between each light-emitting compartment 41, they are distinguished as light-emitting compartments A1 to A12, starting from the upper left side (the +x and +y ends) in Figure 2. In this specification, "~" indicates multiple components, each distinguished by a number, and means that it includes those listed before and after "~" as well as those numbered in between. For example, light-emitting sections A1 to A12 include 12 light-emitting sections 41, numbered from light-emitting section A1 to light-emitting section A12.

[0016] Each light-emitting section 41 is independently driven by the light-emitting drive unit 6 (see Figure 1) to perform light emission operations. In addition, each light-emitting section 41 emits light when power is supplied to the VCSEL 43 contained in the light-emitting section 41 by the light-emitting drive unit 6. In this embodiment, the power supplied to the VCSEL 43 contained in each light-emitting section 41, and the VCSEL 43 emit light due to the supplied power. The amount of light emitted from each light-emitting section 41 can be adjusted according to environmental factors such as the brightness of the illumination area and operations by the user of the distance measuring device 1. In this embodiment, driving the light-emitting section 41 refers to power being supplied to the VCSEL 43 contained in the light-emitting section 41 so that it emits light, and the light-emitting operation refers to the VCSEL 43 contained in the light-emitting section 41 emitting light for a predetermined period of time. Furthermore, "independently driven" means that each light-emitting section 41 is driven and illuminated individually. The light-emitting drive unit 6 drives each light-emitting section 41 in accordance with the control signal from the control unit 8 (see Figure 1). Therefore, each light-emitting section 41 does not necessarily illuminate all at the same time; for example, in the example in Figure 2, light-emitting section A1 may be emitting light, but light-emitting section A12 may not be emitting light.

[0017] The illumination surface 60 is the surface to which light from the light-emitting unit 4 is irradiated, at a certain distance in the direction (+z direction) from the center 40C of the light-emitting surface 40, and perpendicular to the direction in which light is emitted. In the example shown in Figure 2, the light-emitting unit 4 emits light in the +z direction, so the illumination surface 60 extends in the x and y directions at a certain distance in the +z direction. Here, the central axis Ax (dotted line) passing through the center 60C of the illumination surface 60 and the center 40C of the light-emitting surface 40 is perpendicular to the light-emitting surface 40 and the illumination surface 60. In this embodiment, the illumination surface 60 is rectangular in shape, corresponding to the rectangular shape of the light-emitting surface 40.

[0018] As shown in the figure, the irradiation surface 60 is divided into multiple irradiation sections 61, corresponding to the light-emitting sections 41 on the light-emitting surface 40. In the example in Figure 2, it is divided into 12 irradiation sections 61, with 4 in the x direction and 3 in the y direction. If it is necessary to distinguish between each irradiation section 61, they will be labeled as Irradiation Sections B1 to B12, starting from the upper left side (the +x and +y ends) in Figure 2. In some cases, an illumination area Bi assigned the same number i as an illumination area Bi is referred to as a "corresponding illumination area." For example, illumination area A1 is the illumination area corresponding to illumination area B1. Conversely, an illumination area Bi assigned the same number i as an illumination area Ai is also referred to as a "corresponding illumination area."

[0019] Irradiation sections B1 to B12 are arranged symmetrically with respect to the xy-plane with respect to emission sections A1 to A12. For example, in Figure 2, just as emission sections A1, A2, A3, and A4 are arranged in this order in the -x direction, irradiation sections B1, B2, B3, and B4 are arranged in this order in the -x direction. Each light-emitting section 41 emits light toward its corresponding illumination section 61. Each illumination section 61 is then illuminated by the light emitted from its corresponding light-emitting section 41. Here, "light-emitting section 41 emitting light toward its corresponding illumination section 61" means that the optical axis of the light emitted from each light-emitting section 41 is directed toward its corresponding illumination section 61. It is not limited to all of the light emitted from a light-emitting section 41 illuminating its corresponding illumination section 61. In other words, some of the light emitted from a certain light-emitting section 41 may illuminate an illumination section 61 different from its corresponding illumination section 61, or outside the range of the illumination surface 60.

[0020] Figure 3 shows an example of the light-emitting unit 4 according to this embodiment. Unlike Figure 2, Figure 3 shows the light-emitting unit 4 as viewed from the side that emits light. Therefore, in Figure 3, the right direction on the paper is the +x direction, the top direction on the paper is the +y direction, and the front direction on the paper is the +z direction. As shown in Figure 3, the light-emitting unit 4 has a substrate 42 and a light-emitting surface 40 on which a plurality of VCSELs 43 are arranged. More specifically, the substrate 42 and the light-emitting surface 40 are arranged on top of each other in the direction of light emission (+z direction, the front direction of the paper). Note that the substrate 42 may have wiring for power supply and electrical signal exchange, as well as electronic components related to the operation of the light-emitting unit 4, but these are omitted from the description.

[0021] As described above, the light-emitting unit 4 has 12 light-emitting sections 41 (light-emitting sections A1 to A12) on the light-emitting surface 40, each of which has a VCSEL 43 arranged on it. As shown in Figure 3, all light-emitting sections A1 to A12 have the same area. In addition, each of the light-emitting sections A1 to A12 has the same number of VCSELs 43 (7 in this example) arranged in it. Furthermore, the area of ​​each light-emitting section 41 and the number of VCSELs 43 to be placed are not limited, and some or all of the light-emitting sections 41 may have different areas, and different numbers of VCSELs 43 may be placed in each section.

[0022] The light emitted from each light-emitting section 41 of the light-emitting unit 4 is spread by an irradiation lens section (not shown) into a plane perpendicular to the emission direction (the axial direction of the central axis Ax) and irradiated onto the irradiation surface 60. The irradiation lens section may use optical components such as a diffuser plate provided in the optical path of the light to diffuse the light by scattering, a diffractive optical element (DOE) that changes the angle of incident light before emission, and / or a lens.

[0023] (Light receiving part 5) Figure 4 is a diagram illustrating the relationship between the light-receiving surface 50 of the light-receiving unit 5 according to this embodiment and the illumination surface 60 described above. In Figure 4, as in Figure 2, the left direction of the paper is the +x direction, the top direction of the paper is the +y direction, and the back direction of the paper is the z direction, with the opposite directions being the -x, -y, and -z directions, respectively. Note that in Figure 4, the light-receiving surface 50 and the illumination surface 60 are shown offset in the vertical direction (±y direction) of the paper, but in reality, the light-receiving surface 50 and the illumination surface 60 are arranged to face each other. In Figure 4, the light-receiving unit 5 (light-receiving surface 50) is located in the front direction (-z direction) of the paper, and the illumination surface 60 is located in the back direction (+z direction) of the paper. In other words, Figure 4 shows the light-receiving unit 5, which receives light reflected from the illumination surface 60, as viewed from the side opposite to the side from which the light-receiving unit 5 receives light.

[0024] The light-receiving unit 5 extends in the x and y directions and has a light-receiving surface 50 on which multiple light-receiving elements (not shown) are arranged. The light-receiving unit 5 receives light that is emitted from the light-emitting unit 4 and reflected by an object on the illumination surface 60, using each of the light-receiving elements. The central axis Bx (dotted line) passing through the center 60C of the illumination surface 60 and the center 50C of the light-receiving surface 50 is perpendicular to the illumination surface 60 and the light-receiving surface 50. In this embodiment, the light-receiving surface 50 is rectangular in shape, similar to the light-emitting surface 40 (see Figure 2) and the illumination surface 60.

[0025] The light-receiving surface 50 is divided into multiple light-receiving sections 51, corresponding to the light-emitting section 41 (see Figure 2) of the light-emitting surface 40 (see Figure 2) and the irradiation section 61 of the irradiation surface 60. In the example in Figure 4, it is divided into 12 light-receiving sections 51, with 4 in the x direction and 3 in the y direction. If it is necessary to distinguish between each light-receiving section 51, they are distinguished as light-receiving sections C1 to C12, starting from the upper left side (the +x and +y ends) in Figure 4. In some cases, a light-receiving area Ci assigned the same number i as a light-emitting area Ai or a light-illuminating area Bi is referred to as a "corresponding light-receiving area." For example, light-receiving area C1 is a light-receiving area corresponding to light-emitting area A1 or light-illuminating area B1. Conversely, a light-emitting area Ai assigned the same number as a light-receiving area Ci is referred to as a "corresponding light-emitting area," and a light-receiving area Bi assigned the same number as a light-receiving area Ci is referred to as a "corresponding light-illuminating area."

[0026] The light-receiving sections C1 to C12 are arranged symmetrically with respect to the xy-plane with respect to the illumination sections B1 to B12. For example, in Figure 4, the light-receiving sections C1, C2, C3, C4 are arranged in the same order in the -x direction as the illumination sections B1, B2, B3, B4 are arranged in the same order in the -x direction. Each light-receiving section 51 receives light emitted from the light-emitting section 4 and reflected by an object located in the corresponding irradiation section 61.

[0027] Each light-receiving section 51 has multiple light-receiving elements arranged in a regular pattern. Each light-receiving element receives light emitted from the light-emitting section 4 and reflected by an object on the illumination surface 60, and can output an electrical signal according to the received light. Examples of light-receiving elements include photodiodes and phototransistors.

[0028] Each light-receiving section 51 is independently driven by the light-receiving drive unit 7 (see Figure 1) to perform light-receiving operations. Here, driving a light-receiving section 51 means bringing the light-receiving section 51 into a state where it can accumulate charge in response to light reception by the light-receiving element, and light-receiving operation means that the light-receiving element of the light-receiving section 51 accumulates charge in response to light reception. Furthermore, "independently driven" means driving each light-receiving section 51 individually to bring it into a state where it can accumulate charge in response to light reception. The light-receiving drive unit 7 drives each light-receiving section 51 in response to a control signal from the control unit 8 (see Figure 1). Furthermore, the light receiving unit 5 outputs an electrical signal to the control unit 8 corresponding to the charge accumulated in the light receiving section 51, that is, the result of light reception in the light receiving section 51, in accordance with the readout operation of the control unit 8 (details will be described later).

[0029] Figure 5 illustrates an example of the irradiation sequence for the irradiation sections 61 of the irradiation surface 60. In one example of the sequence shown in Figure 5, irradiation of the irradiation section 61 is performed sequentially in the direction of arrow 64. That is, when the irradiation section 61 is divided into upper, middle, and lower sections, the irradiation is performed in the order of upper section B1-B4, middle section B5-B8, and lower section B9-B12. In the upper section, the order is B1-B4. In the middle section, the direction is the opposite of the upper section, and the order is B8-B5. In the lower section, the direction is the same as the upper section, and the order is B9-B12.

[0030] The emission of light from the light-emitting section 41 of the light-emitting unit 4 is driven in the order of arrows 44 so that the irradiation of the irradiation section 61 is in the order of arrows 64. In addition, the reception of light from the light-receiving section 51 of the light-receiving unit 5 in response to the reflected light from the irradiation section 61 is driven in the order of arrows 54, which correspond to arrows 64.

[0031] (Control Unit 8) Returning to Figure 1, the control unit 8 is composed of a CPU (Central Processing Unit) 81, a ROM (Read Only Memory) 82, and a RAM (Random Access Memory) 83. CPU81 is an example of a processor that loads various programs stored in ROM82, etc., into RAM83 and executes them to realize the functions described later. RAM83 is memory used as working memory for CPU81, etc. ROM82 is memory that stores various programs, etc., that are executed by CPU81.

[0032] Here, the program executed by the CPU 81 may be provided stored on a computer-readable recording medium such as a magnetic recording medium (magnetic tape, magnetic disk, etc.), an optical recording medium (optical disk, etc.), a magneto-optical recording medium, or semiconductor memory. Alternatively, the program executed by the CPU 81 may be provided using communication means such as the Internet.

[0033] In this embodiment, each process is executed on any computer. Furthermore, any computer may execute these processes using a processor as hardware, a program as software, or a combination thereof. In that case, the processor is configured to work in cooperation with the program to execute the various processes in this embodiment, and can function as a unit or means in this embodiment. Also, the execution order of the processes by the processor is not limited to the order described and may be changed as appropriate. Any computer may be a general-purpose computer, a computer designed for a specific purpose, a workstation, or any other system capable of executing each process.

[0034] A processor may consist of one or more hardware components, and the type of hardware is not limited. For example, a processor may consist of a CPU (Central Processing Unit), an MPU (Micro Processing Unit), a programmable logic device such as an FPGA (Field Programmable Gate Array), a dedicated circuit for executing a specific process such as an ASIC (Application Specific Integrated Circuit), a GPU (Graphic Processing Unit), or an NPU (Neural Processing Unit). Furthermore, the type of hardware may be a combination of different types of hardware. When multiple hardware components are configured to execute one or more processes of a processor, these components may reside in physically separate devices or in the same device. Also, in any embodiment, the order of each process performed by the processor is not limited to the order described above and may be changed as appropriate. Hardware is composed of electrical circuits (circuitry) that combine circuit elements such as semiconductor elements.

[0035] Furthermore, the program may be firmware or software such as microcode. Alternatively, the program may be, for example, a set of program modules, each function of which may be implemented by a processor configured to perform its respective function. The program may be program code or multiple code segments stored on one or more non-temporary computer-readable media (e.g., storage media or other storage). The program may be divided and stored on multiple non-temporary computer-readable media located on physically separate devices. Program code or code segments may represent any combination of procedures, functions, subprograms, routines, subroutines, modules, software packages, classes, or instructions, data structures, or program statements. Program code or code segments may be connected to other code segments or hardware circuits by sending and receiving information, data, arguments, parameters, or memory contents.

[0036] The control unit 8 controls the light emission operation of the light emission unit 4 through the light emission drive unit 6, and controls the light receiving operation of the light receiving unit 5 through the light receiving drive unit 7. Furthermore, the control unit 8 performs a readout operation on the light receiving unit 5 through the light receiving drive unit 7. Here, "readout operation" means that the control unit 8 controls the light receiving unit 5 through the light receiving drive unit 7 and outputs an electrical signal corresponding to the result of light reception by the light receiving element in the light receiving section 51, and acquires the result of light reception for each light receiving section 51. In this embodiment, the control unit 8 can perform a readout operation independently for each light receiving section 51. For example, if one light receiving section Ci and another light receiving section Cj are performing a light reception operation and accumulating charge, the control unit 8 can perform a readout operation on both light receiving section Ci and light receiving section Cj, or it can perform a readout operation on only light receiving section Ci.

[0037] The control unit 8 measures the distance of each irradiation area 61 based on the light reception results in each light receiving area 51. Then, it combines the distance measurement results in each irradiation area 61 and creates a distance image representing the distance between the distance measuring device 1 and the object. More specifically, the control unit 8 applies predetermined calculation processing to the four electrical signals obtained from the light receiving unit 5 as the results of four light receptions in each light receiving area 51. This calculates (measures) the distance between the distance measuring device 1 and the object in each irradiation area 61 of the irradiation surface 60 and creates a distance image.

[0038] <Distance image 100> Figure 6 illustrates the distance image 100 in this embodiment. (a) shows the positional relationship between the distance measuring device 1 and the objects S1 and S2, (b) shows the appearance of the illumination surface 60, and (c) shows an example of the distance image 100 created by the control unit 8. The distance image 100 shown in Figure 6(c) was created as a result of measuring the distance for all illuminated sections 61 on the illuminated surface 60. In the example in Figure 6, the objects S1 and S2 (sometimes referred to simply as object S) were stationary and did not change their position relative to the distance measuring device 1, at least from the start to the completion of the distance measurement necessary for creating the distance image 100.

[0039] As shown in Figure 6(c), the distance image 100 has multiple image sections 101 corresponding to the light-emitting section 41 of the light-emitting surface 40, the illumination section 61 of the illumination surface 60, and the light-receiving section 51 of the light-receiving surface 50 (see Figures 2 and 4). In the example in Figure 6(c), the distance image 100 has 12 image sections 101, four arranged horizontally in the figure corresponding to the ±x directions of the illumination surface 60 and the light-receiving surface 50, and three arranged vertically in the figure corresponding to the ±y directions. If it is necessary to distinguish between each image section 101, they are distinguished as image sections D1 to D12 in order from the upper left in Figure 6(c).

[0040] In the distance image 100, the image section Di is an image obtained based on light emitted from the light-emitting section Ai of the light-emitting surface 40, reflected by the object at the illumination section Bi of the illumination surface 60, and received at the light-receiving section Ci of the light-receiving surface 50. Note that an image section Di assigned the same number i to the light-emitting section Ai, illumination section Bi, and light-receiving section Ci may be referred to as the "corresponding image section." Conversely, an image section Di assigned the same number i to the light-emitting section Ai may be referred to as the "corresponding light-emitting section." Furthermore, an illumination section Bi assigned the same number i to the image section Di may be referred to as the "corresponding illumination section," and a light-receiving section Ci assigned the same number to the image section Di may be referred to as the "corresponding light-receiving section."

[0041] Each image section 101 of the distance image 100 has multiple pixels (not shown) associated with multiple light-receiving elements in the corresponding light-receiving section 51. In the distance image 100, the pixel value of each pixel in the image section 101 corresponds to the distance from the distance measuring device 1 to the object, calculated from the electrical signals from each light-receiving element in the light-receiving section 51.

[0042] In the example shown in Figure 6(a), objects S1 and S2 are located at a certain distance from the distance measuring device 1. As shown in Figure 6(b), in this example, object S1 is located in the area spanning irradiation sections B1, B5, and B9 of the irradiation surface 60, and object S2 is located in the area spanning irradiation sections B2 and B6. Furthermore, the distance from the distance measuring device 1 to object S1 (for example, about 1 m) is smaller than the distance from the distance measuring device 1 to object S2 (for example, about 3 m).

[0043] As shown in Figure 6(c), the depth image 100 depicts an image S1' representing object S1 and an image S2' representing object S2 (sometimes referred to simply as image S') using pixels contained in each image section 101. More specifically, image S1' is depicted across image sections D1, D5, and D9 of the depth image 100, corresponding to illumination sections B1, B5, and B9, and image S2' is depicted across image sections D2 and D6 of the depth image 100, corresponding to illumination sections B2 and B6. In this example, information relating to the distance from the distance measuring device 1 to object S1 and the distance from the distance measuring device 1 to object S2 can be obtained from the pixel values ​​of the pixels that make up images S1' and S2' in the distance image 100 (represented by shading in Figure 6(c)).

[0044] Furthermore, since the distance image 100 includes distance information between each point on the surface of the object S and the distance measuring device 1, it can also be considered to include information about the three-dimensional shape of the object S. Therefore, the distance measuring device 1 to which this embodiment is applied can also be used for three-dimensional measurement.

[0045] <Example of a schematic configuration of distance measuring device 1> Figure 7 is a perspective view showing a schematic configuration example of the distance measuring device 1 to which this embodiment is applied. The distance measuring device 1 illustrated in Figure 7 comprises at least a housing 1a and a printed circuit board 1b housed within the housing 1a. Note that in Figure 7, some parts of the housing 1a are omitted from the illustration.

[0046] The printed circuit board 1b is equipped with the aforementioned light-emitting unit 4 and light-receiving unit 5, which constitute the optical device 3. The printed circuit board 1b is also equipped with the CPU 81, ROM 82, and RAM 83 (see Figure 1), which constitute the control unit 8.

[0047] To further explain, in the configuration example shown in Figure 7, the light-emitting unit 4 comprises four light sources 410, 420, 430, and 440. Each of the light sources 410 to 440 has a light-emitting surface 40 (see, for example, Figure 3) which is divided into a plurality of light-emitting sections 41. The light sources 410 to 440 are arranged around the light-receiving unit 5. Note that while Figure 7 shows an example with four light sources 410-440, it is also possible to have a number other than four, such as two, three, or five light sources.

[0048] Here, if the light-emitting unit 4 is equipped with multiple light sources 410 to 440, consider the case where, for example, the light from each of the multiple light sources 410 to 440's light-emitting section A1 is irradiated onto, for example, irradiation section B1 of the irradiation sections B1 to B12 (see, for example, Figure 2) of the irradiation surface 60. When irradiating with the light from the light-emitting section A1 of multiple light sources 410 to 440, the irradiation section B1 (see, for example, Figure 2) can be irradiated with a higher energy density compared to irradiating with the light from the light-emitting section A1 of just one light source, for example, light source 410. Also, when irradiating the irradiation section B1 with the light from each of the multiple light sources 410 to 440's light-emitting section A1, the exposure time of the light-receiving element (not shown) in the light-receiving section C1 (see, Figure 4) of the light-receiving unit 5 is shortened, and the acquisition of the global component, which is background light, can be suppressed. As a result, outdoor long-distance distance measurement becomes possible.

[0049] However, due to variations during assembly, it is difficult to match the illumination area of ​​the illumination surface 60 by multiple light sources 410-440 with the light-receiving area of ​​the light-receiving section 51 corresponding to the illumination section 61. As a result, an unilluminated area may occur in the illumination section 61, and if this results in an unexposed area in the light-receiving section 51, the distance measurement error may increase. Therefore, in this embodiment, when irradiating a predetermined irradiation area 61 (see, for example, Figure 2) with multiple light sources 410 to 440, a configuration is adopted in which there are no unirradiated areas, thereby suppressing distance measurement errors caused by unirradiated areas. This will be explained below.

[0050] <Light source 410~440> Figure 8 is a diagram illustrating the configuration of the light sources 410-440 provided in the light-emitting unit 4, and each of the light sources 410-440 is driven to illuminate only its respective light-emitting section A1. Focusing on light sources 410 and 440 shown in Figure 8, the illumination angle of light source 410 is θ1, and the illumination angle of light source 440 is θ2. Irradiation angles θ1 and θ2 are different angles from each other. More specifically, when light emission section A1 of light source 410 emits light, the irradiation angle of the light is θ1, and when light emission section A1 of light source 440 emits light, the irradiation angle of the light is θ2. Irradiation angle θ2 is larger than irradiation angle θ1 (θ2 > θ1), and at irradiation angle θ2, the light is diffused compared to irradiation angle θ1. The illumination angles θ1 and θ2 referred to here are angles that indicate the degree of light spread from the light-emitting section A1, and refer to the angles at which the light intersects with the vertical plane in the light-emitting section A1.

[0051] In light source 410, light-emitting sections A2 to A12 (see Figure 2), other than light-emitting section A1, also have an illumination angle of θ1. In light source 440, light-emitting sections A2 to A12 (see the same figure), other than light-emitting section A1, also have an illumination angle of θ2.

[0052] In this embodiment, the irradiation angle of light when light-emitting sections A1 to A12 (see Figure 2) in the other light sources 420 and 430 emit light is θ1, the same as in the case of light source 410. Therefore, in this embodiment, among the light sources 410 to 440, the light sources with an irradiation angle of θ1 are light sources 410 to 430, and the light source with an irradiation angle of θ2 is light source 440. When light source 410 emits light, the other light sources 420 to 440 also emit light.

[0053] Thus, when the light-emitting unit 4 is equipped with four light sources 410 to 440, only one light source, light source 440, has an illumination angle of θ2, but this is not limited to this. For example, it is conceivable to have two light sources, light sources 430 and 440, with an illumination angle of θ2. However, it is preferable to have one light source with an illumination angle of θ2 rather than two. In other words, it is preferable that the number of light sources with an illumination angle of θ2 is less than the number of light sources with an illumination angle of θ1. This is because if the number of light sources with an illumination angle of θ2 increases, the effect of flare will increase when a highly reflective material is located on the illumination surface 60.

[0054] Although not shown in the diagram, if the number of light sources provided by the light-emitting unit 4 is other than 4, for example, if it is equipped with 6 light sources, it is conceivable that there may be one, two, or three light sources with an illumination angle of θ2. In this case as well, for the reasons mentioned above, it is preferable to have fewer light sources with an illumination angle of θ2 than fewer light sources with an illumination angle of θ1.

[0055] Figure 9 illustrates an example configuration when optical elements are arranged in light sources 410-440. (a) and (b) show an example using microlenses 450 and 460 as optical elements, while (c) and (d) show another example using lenses 470 and 480 as optical elements. Note that (a) to (d) show an example configuration of light-emitting sections A1 and A2 of light sources 410-440, but the other light-emitting sections A3 to A12 are the same and are not shown. Light sources 410-440 emit light from the upper side of Figure 9.

[0056] In the example shown in Figures 9(a) and (b), a configuration is adopted in which a microlens is provided for each light-emitting section A1 and A2 of the light sources 410 to 440. That is, as shown in Figure 9(a), a microlens 450 is provided for each of the light-emitting sections A1 and A2 of the light sources 410 to 430. Also, as shown in Figure 9(b), a microlens 460 is provided for each of the light-emitting sections A1 and A2 of the light source 440. Therefore, in the light sources 410 to 430, the number of light-emitting sections is the same as the number of microlenses 450. Similarly, in the light source 440, the number of light-emitting sections is the same as the number of microlenses 460. The microlens 450 of light sources 410-430 has optical properties that achieve an illumination angle θ1 (see Figure 8). The microlens 460 of light source 440 has optical properties that achieve an illumination angle θ2 (see the same figure).

[0057] Furthermore, if the light sources 410-440 each have predetermined illumination angles, the illumination angles θ1 and θ2 are realized by combining them with the illumination angles of the microlenses 450 and 460. Further explanation will be provided regarding the predetermined illumination angles of light sources 410-440. The illumination angle is set to a predetermined angle by changing, for example, the aperture of the light-emitting element of light sources 410-440. The predetermined illumination angles referred to here may be the same for all light sources 410-440, or they may be the same for some of the light sources. In the latter case, the predetermined illumination angles of the other light sources will differ from the predetermined illumination angles of some of the light sources. For example, if the predetermined illumination angles of light sources 410-430 are the same, then the predetermined illumination angle of light source 440 will differ from the predetermined illumination angles of light sources 410-430.

[0058] In other examples shown in Figures 9(c) and (d), a configuration is adopted in which a single lens is provided across the light-emitting sections A1 and A2 of the light sources 410 to 440. That is, as shown in Figure 9(c), the same lens 470 is provided across the light-emitting sections A1 and A2 of the light sources 410 to 430. Also, as shown in Figure 9(d), the same lens 480 is provided across the light-emitting sections A1 and A2 of the light source 440.

[0059] In light sources 410 to 430, one lens 470 is provided for each of the multiple light-emitting sections A1 and A2, and in light source 440, one lens 480 is provided for each of the multiple light-emitting sections A1 and A2. Therefore, in each of the light sources 410 to 430, the number of lenses 470 is less than the number of light-emitting sections A1 to A12 (see Figure 2). Also, in light source 440, the number of lenses 480 is less than the number of light-emitting sections A1 to A12 (see Figure 2). Furthermore, a configuration in which one lens 470 or lens 480 is provided for each light-emitting section A1 to A12 is also conceivable.

[0060] The lens 470 of light sources 410-430 has optical properties that achieve an illumination angle θ1 (see Figure 8). The lens 480 of light source 440 has optical properties that achieve an illumination angle θ2 (see the same figure). Furthermore, if each of the light sources 410 to 440 has a predetermined illumination angle, the illumination angles θ1 and θ2 are realized by combining them with the illumination angles of the lenses 470 and 480. The predetermined illumination angles of the light sources 410 to 440 themselves are the same as in Figures 9(a) and (b), and their explanation is omitted.

[0061] Thus, the light source 440 is equipped with a microlens 460 or lens 480 that makes the illumination angle larger than that of the light sources 410-430. Microlenses 450, 460 and lenses 470, 480 are examples of optical components.

[0062] Figure 10 is a diagram illustrating the light intensity distribution of the light receiving section C1 of the light receiving unit 5 due to light from multiple light sources 410 to 440. Note that Figure 10 shows the light-receiving area C1, etc., but it can also be viewed as the illumination area B1 (see Figure 4), etc. In this case, illumination area B1 is an example of one region, and illumination areas B2, B5, and B6, which correspond to the light-receiving areas C2, C5, and C6, are examples of regions adjacent to one region. Furthermore, regions 411 to 431, which will be described later, are examples of the range illuminated by one light-emitting area in other light sources. Region 441 is an example of the range illuminated by one light-emitting area in some light sources.

[0063] Due to variations during assembly as described above, the light from light sources 410-430 (see, for example, Figure 8) is received shifted to the upper left of the light receiving section C1 in the example shown in Figure 10. Specifically, the light from light source 410 is in the region 411 indicated by the dashed line, the light from light source 420 is in the region 421 indicated by the dashed line, and the light from light source 430 is in the region 431 indicated by the dashed line. The light-receiving section C1 contains a region 401 (indicated by the upper right diagonal line) that is not exposed by any of the light sources 410 to 430. This prevents multipath noise from occurring from areas far outside the area that the light-receiving section C1 is trying to receive light from.

[0064] To explain further, of the multiple light sources 410-440, the light from light source 440 is located in the region 441 shown by the solid line. The light from light source 440 exposes not only the light-receiving area C1, but also the light-receiving areas C2, C5, and C6 located around light-receiving area C1. In other words, the light from light source 440 is received throughout the entire area of ​​light-receiving area C1. Therefore, the aforementioned region 401 is exposed by the light from light source 440. Region 441 is larger than regions 411, 421, and 431.

[0065] The light-receiving area C1 is divided into two regions: region 401, indicated by the upper right diagonal line, which is exposed only by light from light source 440, and region 402, indicated by the lower right diagonal line, which is exposed by light from at least one of the light sources 410 to 430. More specifically, region 402 is exposed by light from at least one of the light sources 410 to 430, as well as by light from light source 440. Even with variations during assembly, there are no areas in the light-receiving section C1 that are not exposed by any of the light sources 410-440. Figure 10 shows the case of light-receiving section C1 of the light-receiving unit 5, but the other light-receiving sections C2 to C12 (see Figure 4) are similar, so their explanation is omitted.

[0066] (Description of Examples and Comparative Examples) Next, the distance measurement results obtained from the distance image 100 (see Figure 6) will be explained using Figures 11 and 12. Figure 11 shows an example (single-lamp diffusion) where light sources 410-430 have an illumination angle θ1 and light source 440 has an illumination angle θ2 (see Figure 8), and Figure 12 shows a comparative example (four-lamp diffusion) where light sources 410-440 have an illumination angle θ2.

[0067] Figure 11 is a graph illustrating an embodiment, where (a) and (b) show an embodiment in which this embodiment is applied, and (c) shows a conventional example in which this embodiment is not applied to show the difference from the embodiment. More specifically, Figure 11(a) shows the case where the illumination angle θ2 of light source 440 is 2 degrees greater than the illumination angle θ1 of light sources 410-430 (θ2 = θ1 + 2 degrees). (b) shows the case where the illumination angle θ2 of light source 440 is 5 degrees greater than the illumination angle θ1 of light sources 410-430 (θ1 = θ2 + 5 degrees). (c) shows the case where the illumination angle of light sources 410-440 is θ1 for all of them. Figures 11(a) to (c) show the average values ​​over several frames, with the vertical axis representing distance (m) and the horizontal axis representing position in X-pixels. As an example, the case where distances are measured for objects S3 and S4 is shown.

[0068] As shown in Figure 11(a), in the embodiment, the vertical axis of the graph indicates that the distance to object S3 is 5.9m and the distance to object S4 is 6.5m. In contrast, in Figure 11(b), the distance to object S3 is 5.3m and the distance to object S4 is 6.8m. The distances to objects S3 and S4 were more accurate in Figure 11(b) than in Figure 11(a). Furthermore, the range of variation in the intervals corresponding to objects S3 and S4 is smaller in Figure 11(b) than in Figure 11(a). From the horizontal axis of the graph, object S3 exists between 150 and 300, and object S4 exists between 330 and 500. Therefore, the distance measurement results were better when the illumination angle θ2 was 5 degrees larger than the illumination angle θ1. This indicates that a larger illumination angle θ2 results in better illumination with weaker light. In contrast, in the conventional example shown in Figure 11(c), it is difficult to confirm the existence of objects S3 and S4.

[0069] Figure 12 is a graph illustrating a comparative example, where (a) and (b) show the case where the illumination angle of all light sources 410 to 440 is θ2 (four-lamp diffused). (a) shows the case where the illumination angle θ2 is 2 degrees greater than the illumination angle θ1 (see Figure 8) (θ1 = θ2 + 2 degrees), and (b) shows the case where the illumination angle θ2 is 5 degrees greater than the illumination angle θ1 (see Figure 8) (θ1 = θ2 + 5 degrees). Figures 12(a) and (b) show the average values ​​over several frames, with the vertical axis representing distance (m) and the horizontal axis representing position in X-pixels. As a comparative example, the case where distances were measured for objects S3 and S4, as in the example, is shown.

[0070] Referring to Figure 12(a), the graph is not clean enough to identify that there are two objects. Furthermore, referring to Figure 12(b), it is more difficult to identify the presence of two objects than in Figure 12(a), and even more difficult to infer the presence of two objects.

[0071] In Figure 11, which shows the case of a single-lamp diffused beam, the distance measurement accuracy is higher in (b) than in (a). However, in Figure 12, which shows the case of a four-lamp diffused beam, the distance measurement accuracy is higher in (a) than in (b). In other words, the distance measurement accuracy is lower in the case of a four-lamp diffused beam compared to the case of a single-lamp diffused beam.

[0072] To elaborate further, although not visible in the distance image 100 (see Figure 6(c)), a highly reflective material exists near the object S3. The presence of such a highly reflective material may cause light reflected by it to affect the distance image 100. More specifically, the reflected light from the highly reflective material may be received in the portion of the distance image 100 corresponding to the objects S3 and S4.

[0073] By setting the irradiation angle to θ2, light diffusion occurs, and light is irradiated over a wider area than when the irradiation angle is θ1. In the comparative example, by setting the irradiation angle of all light sources 410 to 440 to θ2, stronger light is irradiated over a wider area compared to when the irradiation angle is θ1. Therefore, in the comparative example, stronger light is irradiated to objects other than the target objects S3 and S4 compared to the example, and strong reflected light is received by the light receiving unit 5. It is thought that this effect leads to a decrease in the accuracy of distance measurement. In this embodiment, light source 440 among the light sources 410 to 440 is set to an illumination angle θ2, eliminating the unilluminated area and improving the distance measurement accuracy. However, setting all of the light sources 410 to 440 to an illumination angle θ2, as in the comparative example, would actually lead to a decrease in distance measurement accuracy.

[0074] It is preferable that the number of light sources with an illumination angle θ2 is less than the number of light sources with an illumination angle θ1. Having only one light source at an illumination angle θ2 is preferable (single-lamp diffusion). Even when there are highly reflective materials near the target objects S3 and S4, single-lamp diffusion can suppress the effects of flare while mitigating the decrease in distance measurement accuracy.

[0075] (Explanation of variations) Figure 13 illustrates a modified example and corresponds to Figure 10 described above. The modified example shown in Figure 13 illustrates a case where the light-receiving unit 5 is divided into two light-receiving sections C1 and C2. In this case, there are two light-emitting sections, the same number as the light-receiving sections, and there are also two illumination sections. Furthermore, the modified example in Figure 13 is equipped with two light sources, with the illumination angle of one light source being θ1 and the illumination angle of the other being θ2. The light from the light source with illumination angle θ1 is in the region 411 shown by the dashed line, and the light from the light source with illumination angle θ2 is in the region 421 shown by the solid line. Light from a light source with an illumination angle θ2 is directed towards the entire area of ​​receiving section C1 and the adjacent receiving section C2. Therefore, in the modified example, when light-receiving section C1 is exposed, light is emitted from two light sources, and when light-receiving section C2 is exposed, light is emitted from a light source with an irradiation angle of θ2.

[0076] (Light-emitting device 2 and rangefinder 1) In Figure 1, the light-emitting device 2, shown by the dashed line, comprises a light-emitting unit 4, a light-emitting drive unit 6, and a control unit 8. This light-emitting device 2 is an example of a light-emitting device characterized by arranging multiple light sources, each having a plurality of light-emitting sections capable of emitting light individually, driving each of the multiple light sources so that only one light-emitting section illuminating a single area is lit, and having an illumination angle greater for some of the multiple light sources than for the illumination angles of the other light sources. Furthermore, the distance measuring device 1 shown in Figure 1 is an example of a distance measuring device comprising a light receiving unit 5 that receives reflected light from a light emitting device 2, an acquisition unit 5 that acquires the results of the light receiving unit 5, and a control unit 8 that measures the distance based on the results of the light receiving unit acquired by the acquisition unit 5. The light receiving unit 5 is an example of a light receiving unit and an example of an acquisition unit. The CPU 81 of the control unit 8 that realizes the distance measuring function is an example of a distance measuring unit.

[0077] <Note> (((1))) A light-emitting device characterized by arranging multiple light sources, each having multiple light-emitting sections capable of emitting light individually, driving each of the multiple light sources so that only one light-emitting section irradiating a particular area is illuminated, and having an irradiation angle greater than that of some of the multiple light sources than that of the other light sources. (((2))) The light-emitting device according to claim 1, characterized in that the one light-emitting section in the part of the light source irradiates over a region adjacent to the one region, and the range irradiated by the one light-emitting section in the part of the light source is wider than the range irradiated by the one light-emitting section in the other light source. (((3))) The light-emitting device according to claim 2, characterized in that the one light-emitting section in the part of the light source irradiates light toward the entire area of ​​the one region and the adjacent region. (((4))) The light-emitting device according to any one of claims 1 to 3, characterized in that the number of some of the light sources is smaller than the number of the other light sources. (((5))) The light-emitting device according to claim 4, characterized in that the number of the aforementioned light sources is one. (((6))) The light-emitting device according to any one of claims 1 to 5, characterized in that the aforementioned part of the light source includes an optical member that makes the irradiation angle larger than the irradiation angle of the other light source. (((7))) The light-emitting device according to claim 6, characterized in that the number of optical members is less than the number of multiple light-emitting compartments. (((8))) A distance measuring device comprising: a light-emitting device according to claim 1; a light-receiving unit that receives reflected light from the light-emitting device; an acquisition unit that acquires the result of light reception by the light-receiving unit; and a distance measuring unit that measures distance based on the result of light reception acquired by the acquisition unit.

[0078] According to the invention of (((1))), it becomes possible to suppress the effect of misalignment of light-emitting sections on a single region compared to the case where multiple light sources have the same illumination angle. According to the invention of (((2))), one light-emitting section of some light sources illuminates an area adjacent to one area, and the range illuminated by one light-emitting section of some light sources is wider than the range illuminated by one light-emitting section of other light sources. Compared to not employing such a configuration, it becomes possible to suppress the effect of displacement of the light-emitting section on one area. According to the invention of (((3))), compared to not employing a configuration in which one light-emitting section of a light source irradiates light toward the entire area of ​​one region and adjacent regions, it becomes possible to suppress the effect of displacement of the light-emitting section toward one region. According to the invention of (((4))), the effect of the presence of highly reflective material can be suppressed compared to not employing a configuration in which the number of some light sources is smaller than the number of other light sources. According to the invention of (((5))), it becomes possible to suppress the effects of the presence of highly reflective materials compared to not employing a configuration in which some light sources are limited to one. According to the invention of (((6))), some light sources can reduce costs compared to a configuration that does not employ an optical element that makes the illumination angle larger than that of other light sources. According to the invention of (((7))), the number of optical elements can be less than the number of multiple light-emitting sections, which can reduce costs compared to not employing such a configuration. According to the invention of (((8))), it becomes possible to suppress the effect of misalignment of light emission areas on a single region compared to the case where multiple light sources have the same illumination angle. [Explanation of Symbols]

[0079] 1... Distance measuring device, 2... Light-emitting device, 4... Light-emitting unit, 5... Light-receiving unit, 6... Light-emitting drive unit, 7... Light-receiving drive unit, 8... Control unit, 41, A1~A12... Light-emitting section, 51, C1~C12... Light-receiving section, 61, B1~B12... Irradiation section, 81... CPU, 410, 420, 430, 440... Light source, 450, 460... Microlens, 470, 480... Lens, θ1, θ2... Irradiation angle

Claims

1. Multiple light sources, each having multiple light-emitting sections capable of emitting light individually, are arranged. Each of the multiple light sources is driven to illuminate only one light-emitting section that directs light towards a specific area. The illumination angle of some of the aforementioned multiple light sources is greater than the illumination angle of the other light sources. A light-emitting device characterized by the following features.

2. The light-emitting section of the aforementioned part of the light source illuminates over a region adjacent to the aforementioned region, The area illuminated by one light-emitting section in one of the aforementioned light sources is wider than the area illuminated by the same light-emitting section in the other light sources. The light-emitting device according to feature 1.

3. The light-emitting section of the aforementioned part of the light source irradiates light toward the entire area of ​​the first region and the adjacent region. The light-emitting device according to feature 2.

4. The number of some of the light sources is smaller than the number of the other light sources. The light-emitting device according to feature 1.

5. The number of the aforementioned light sources is one. The light-emitting device according to feature 4.

6. Some of the aforementioned light sources include an optical element that makes the irradiation angle larger than the irradiation angle of the other light sources. The light-emitting device according to feature 1.

7. The number of optical elements is less than the number of multiple light-emitting sections. The light-emitting device according to feature 6.

8. The light-emitting device according to claim 1, A light receiving unit that receives reflected light from the light-emitting device, An acquisition unit that acquires the result of light reception by the light receiving unit, A distance measuring unit that measures distance based on the light reception results acquired by the acquisition unit, A rangefinder equipped with the following features.

Images