Light-emitting device and distance-measuring device

Abstract

To suppress formation of a non-radiation region (a region on which light is not radiated) between radiation regions more than when there is no intersections of light radiated from a plurality of light sources to different radiation regions, when light is radiated to different radiation regions from a plurality of light sources.SOLUTION: A light-emitting device includes: a light emission unit for emitting light; an optical system for enlarging the irradiation range of light emitted from the light emission unit as the radiation light becomes distant from the light emission unit; and a plurality of light sources each having the light-emission unit and the optical system and radiating light to different radiation regions, the center lines of light radiated from the light sources to the radiation region intersecting with one another.SELECTED DRAWING: Figure 3

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a vehicle lamp including a plurality of light sources and a plurality of projection optical systems corresponding to the plurality of light sources, wherein at least one of the plurality of light sources is arranged in a state shifted from the optical axis of the projection optical system corresponding to the light source.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is a distance measuring device that irradiates an object with light using a light-emitting device and measures the distance to the object from the result of receiving the light reflected by the object. When using a light-emitting device that irradiates different irradiation regions with light from a plurality of light sources, a non-irradiation region where no light is irradiated may be formed between the irradiation regions where light is irradiated from each light source. In the non-irradiation region, since the object is not irradiated with light, it becomes difficult to measure the distance to the object in the distance measuring device. An object of the present invention is to suppress the formation of a non-irradiation region where no light is irradiated between irradiation regions when irradiating different irradiation regions with light from a plurality of light sources, as compared with the case where the center lines of the light irradiated from the plurality of light sources to the irradiation regions do not intersect.

Means for Solving the Problems

[0005] The invention according to claim 1 is a light emitting device having a light emitting unit that emits light, an optical system that expands the irradiation range of the light emitted from the light emitting unit as it moves away from the light emitting unit, and a plurality of light sources each having the light emitting unit and the optical system and irradiating light on different irradiation regions, wherein the center lines of the light irradiated from each of the light sources on the irradiation region intersect each other. The invention according to claim 2 further includes a housing that houses the plurality of light sources, and the intersection portion where the center lines of the light irradiated from the plurality of light sources on the irradiation region intersect is located inside the housing, which is the light emitting device according to claim 1. In the invention according to claim 3, the light emitting unit of each of the light sources includes a plurality of light emitting sections that irradiate light toward each of the irradiation sections obtained by dividing the irradiation region into a plurality of sections, and further includes a driving unit that drives the light emitting unit of each of the light sources to individually light the plurality of light emitting sections of the light emitting unit, and the driving unit does not simultaneously light the light emitting sections that irradiate light on the irradiation sections adjacent to each other in different irradiation regions, which is the light emitting device according to claim 1. In the invention according to claim 4, in the irradiation section where the light irradiated from each of the light sources on the irradiation region overlaps, the driving unit lights the light emitting section of one of the light sources that irradiates light on the first irradiation section, which is one of the irradiation sections, and does not light the light emitting section of the other light source that irradiates light on the second irradiation section, which is the other irradiation section, and lights the light emitting sections that irradiate light on the other irradiation sections other than the first irradiation section and the second irradiation section, which is the light emitting device according to claim 3. In the invention according to claim 5, the optical system and the light emitting unit each of the plurality of light sources has have the same characteristics, and the plurality of light sources have different relative positions of the optical system and the light emitting unit so that there is no gap between different irradiation regions when the distance from the plurality of light sources is a predetermined reference distance, which is the light emitting device according to claim 1. The invention according to claim 6 is the light-emitting device according to claim 1, wherein the plurality of light sources include a first light source and a plurality of second light sources arranged side by side in a first direction intersecting the optical axis of the optical system with respect to the first light source, and the center line of the light emitted from the first light source intersects any of the center lines of the light emitted from the plurality of second light sources. The invention according to claim 7 is the light-emitting device according to claim 6, wherein the positions of the intersection portions where the center line of the light emitted from the first light source intersects the center lines of the light emitted from the respective second light sources coincide. The invention according to claim 8 is the light-emitting device according to claim 1, wherein the plurality of light sources include a first light source, a second light source arranged side by side in a first direction intersecting the optical axis of the optical system with respect to the first light source, and a third light source arranged side by side in a second direction intersecting the optical axis and the first direction with respect to the first light source, and the center line of the light emitted from the first light source intersects at least one of the center line of the light emitted from the second light source and the center line of the light emitted from the third light source. The invention according to claim 9 is the light-emitting device according to claim 8, wherein the center line of the light emitted from the first light source intersects both the center line of the light emitted from the second light source and the center line of the light emitted from the third light source. The invention according to claim 10 is a light-emitting device including a light-emitting unit that emits light, an optical system that expands the irradiation range of the light emitted from the light-emitting unit as the distance from the light-emitting unit increases, and a plurality of light sources each having the light-emitting unit and the optical system and irradiating light to different irradiation regions, wherein the arrangement of the plurality of light sources and the arrangement of the plurality of irradiation regions irradiated with light from the plurality of light sources at a predetermined distance from the plurality of light sources on an irradiation surface are inverted. The invention according to claim 11 is a distance measuring device including the light-emitting device according to any one of claims 1 to 10, a light-receiving unit that receives the light irradiated from the light-emitting device and reflected by an object, and a distance measuring unit that measures the distance to the object based on the result of the light reception by the light-receiving unit. The invention according to claim 12 is the distance measuring device according to claim 11, wherein the light receiving unit receives light reflected at a position farther from the light emitting device than the intersection where the center lines of the light irradiated from the plurality of light sources to the irradiation region intersect.

Advantages of the Invention

[0006] According to the inventions of claims 1, 10, and 11, when irradiating light to different irradiation regions with a plurality of light sources, it is possible to suppress the formation of a non-irradiation region where light is not irradiated between the irradiation regions as compared with the case where the center lines of the light irradiated from the plurality of light sources to the irradiation region do not intersect. According to the invention of claim 2, it is possible to suppress the irradiation of an excessive amount of light to the object as compared with the case where the intersection where the center lines of the light irradiated from the plurality of light sources to the irradiation region intersect is located outside the housing. According to the invention of claim 3, it is possible to suppress the non-uniformity of the amount of light irradiated to the irradiation region as compared with the case of simultaneously lighting the light emitting sections that irradiate light to the adjacent irradiation sections in different irradiation regions. According to the invention of claim 4, when lighting the light emitting section of one light source that irradiates light to the first irradiation section and not lighting the light emitting section of the other light source that irradiates light to the second irradiation section, it is possible to reduce the time required to irradiate light to all the irradiation sections as compared with the case of not lighting the light emitting sections that irradiate light to the other irradiation sections other than the first irradiation section and the second irradiation section. According to the invention of claim 5, it is less likely to form a non-irradiation region between adjacent irradiation regions as compared with the case where the relative position between the optical system and the light emitting section is not determined so that there is no gap between different irradiation regions. According to the invention of claim 6, it is possible to narrow the range in which the non-irradiation region is formed as compared with the case where the center line of the light irradiated from the first light source intersects only one of the center lines of the light emitted from the plurality of second light sources. According to the invention of claim 7, it is possible to further narrow the range in which the non-irradiation region is formed as compared with the case where the positions of the intersections where the center line of the light emitted from the first light source intersects the center lines of the light emitted from the respective second light sources do not coincide. According to the invention of claim 8, compared with the case where the center line of the light emitted from the first light source does not intersect the center line of the light emitted from the second light source or the third light source, the range in which the non-irradiation region is formed can be narrowed. According to the invention of claim 9, compared with the case where the center line of the light emitted from the first light source intersects only the center line of the light emitted from one of the second light source and the third light source, the range in which the non-irradiation region is formed can be narrowed. According to the invention of claim 12, compared with the case where the light receiving unit receives the light reflected at the intersection where the center lines of the light intersect, it is possible to suppress excessive light from entering the light receiving unit.

Brief Description of the Drawings

[0007]

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Embodiments 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 embodiments and those obtained by making various changes or improvements to these embodiments are also included in the technical scope of the present invention.

[0009] [Embodiment 1] (Distance Measuring Device 1) FIG. 1 is a block diagram showing an example of the schematic configuration of the distance measuring device 1 to which the present embodiment is applied. The distance measuring device 1 measures the distance to the object based on the time from the timing when light is emitted from the light emitting unit 4 to 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 of measuring 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 of directly measuring 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 irradiates light toward a predetermined range, a light receiving unit 5 that receives light reflected by an object existing in the range irradiated with light from the light emitting unit 4, a light emitting driving unit 6 that drives the light emitting unit 4, and a light receiving driving unit 7 that drives the light receiving unit 5. The light emitting unit 4 is an example of a light emitting device. The light emitting driving unit 6 is an example of a driving unit.

[0011] (Control unit 8) 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 measures the distance from the distance measuring device 1 to the object by the ToF method based on the result of this light reception. The control unit 8 is an example of a distance measuring unit.

[0012] 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. The CPU 81 is an example of a processor, and realizes each function described later by loading various programs stored in the ROM 82 etc. into the RAM 83 and executing them. The RAM 83 is a memory used as a working memory etc. of the CPU 81. The ROM 82 is a memory that stores various programs etc. executed by the CPU 81.

[0013] Here, the program executed by the CPU 81 can be provided in a state stored in 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 a semiconductor memory. Further, the program executed by the CPU 81 may be provided using a communication means such as the Internet.

[0014] In addition, in the present embodiment, the processor refers to a processor in a broad sense, including a general-purpose processor (e.g., CPU: Central Processing Unit, etc.) and a dedicated processor (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic device, etc.). In addition, the operation of the processor in the present embodiment may be achieved not only by one processor but also by a plurality of physically separated processors cooperating with each other. Also, the order of each operation of the processor is not limited to the order described in the present embodiment and may be changed.

[0015] (Light emitting unit 4) FIG. 2 is a diagram showing the light emitting unit 4 of the present embodiment and the irradiation regions 100A and 100B irradiated with the light emitted from the light emitting unit 4. The light emitting unit 4 has a plurality (two in this example) of light sources 4A and 4B that irradiate different irradiation regions 100A and 100B with light. In other words, the light emitting unit 4 has a light source 4A that irradiates the irradiation region 100A with light and a light source 4B that irradiates an irradiation region 100B different from the irradiation region 100A with light. Here, the irradiation region 100A is a region through which the light emitted from the light source 4A passes. Similarly, the irradiation region 100B is a region through which the light emitted from the light source 4B passes. That the irradiation region 100A and the irradiation region 100B are different means that the irradiation region 100A and the irradiation region 100B do not coincide, and they may have an overlapping portion. In addition, the light emitting unit 4 includes a housing 44 (see FIG. 3 described later) that houses the light sources 4A and 4B. The housing 44 has a box-like shape and houses the light sources 4A and 4B inside. Then, the housing 44 emits the light emitted from the light sources 4A and 4B to the outside toward a predetermined range. The relationship between the housing 44 and the irradiation region 100A will be described in detail later.

[0016] FIG. 3 is a diagram for explaining the configurations of light sources 4A and 4B and the behavior of light emitted from light sources 4A and 4B. In FIG. 3, the front side direction of the paper surface is defined as the +x direction, the upward direction of the paper surface is defined as the +y direction, and the rightward direction of the paper surface is defined as the +z direction. The opposite directions are defined as the -x direction, -y direction, and -z direction, respectively. As shown in FIG. 3, light sources 4A and 4B are arranged side by side in the y direction. In this example, light source 4A is arranged on the +y direction side with respect to light source 4B.

[0017] Each of light sources 4A and 4B has a light-emitting chip 41 which is an example of a light-emitting part that emits light in the +z direction. Also, each of light sources 4A and 4B has a lens 42 which is an example of an optical system that expands the irradiation range of the light emitted from the light-emitting chip 41 as it moves away from the light-emitting chip 41 in the +z direction. Further, each of light sources 4A and 4B has a support member 43 that supports the light-emitting chip 41 and the lens 42 so that the light-emitting chip 41 is arranged at a predetermined relative position with respect to the lens 42. Light source 4A and light source 4B have the same configuration except for the relative position of the light-emitting chip 41 with respect to the lens 42.

[0018] The light-emitting chip 41 has a light-emitting surface on which a plurality of vertical cavity surface emitting lasers VCSELs (indicated by reference numeral 45 in FIGS. 7(a) to 7(b) described later) are arranged. Hereinafter, the light-emitting surface of the light-emitting chip 41 included in light source 4A is denoted as light-emitting surface 411, and the light-emitting surface of the light-emitting chip 41 included in light source 4B is denoted as light-emitting surface 412. The light-emitting chip 41 is arranged such that the light-emitting surfaces 411 and 412 are along the xy plane. In this example, as shown in FIGS. 4(a) to 4(b) described later, the light-emitting surfaces 411 and 412 are rectangular in shape having long sides 411x and 412x extending in the x direction and short sides 411y and 412y extending in the y direction. The light-emitting chip 41 emits light in the +z direction from the light-emitting surfaces 411 and 412 by the light emission of the VCSEL.

[0019] Here, the light sources 4A and 4B of the light emitting unit 4 of the present embodiment are each independently driven by a light emission driving unit 6 (see FIG. 1) to perform a light emission operation. Additionally, the light sources 4A and 4B emit light when power is supplied to the VCSELs included in the light sources 4A and 4B by the light emission driving unit 6. Here, "independently driven" means that each of the light sources 4A and 4B is driven to emit light. The light emission driving unit 6 drives each light emitting chip 41 in accordance with a control signal from a control unit 8 (see FIG. 1). Therefore, the light emitting chip 41 of the light source 4A and the light emitting chip 41 of the light source 4B do not necessarily emit light simultaneously. For example, a state where the light emitting chip 41 of the light source 4A is emitting light while the light emitting chip 41 of the light source 4B is not emitting light is possible.

[0020] The lens 42 is provided on the +z direction side with respect to the light emitting chip 41. Additionally, the lens 42 is provided on the downstream side in the direction in which the light emitting chip 41 emits light with respect to the light emitting chip 41. Further, the lens 42 is provided facing the light emitting surfaces 411 and 412 of the light emitting chip 41. As a result, the light emitted from the light emitting surfaces 411 and 412 of the light emitting chip 41 in the +z direction enters the lens 42. Also, the lens 42 is arranged such that the optical axis 420 extends in the z direction. Then, the lens 42 refracts the light emitted from the light emitting chip 41 in a direction intersecting the z direction, thereby expanding the light irradiation range as it goes in the +z direction.

[0021] FIGS. 4(a) to (b) are diagrams for explaining the relationship between the light emitting chip 41 and the lens 42. FIG. 4(a) shows the light emitting chip 41 and the lens 42 in the light source 4A, and FIG. 4(b) shows the light emitting chip 41 and the lens 42 in the light source 4B. FIGS. 4(a) to (b) correspond to views of the light emitting chip 41 and the lens 42 in the light sources 4A and 4B as seen from the -z direction side to the +z direction.

[0022] In FIGS. 4(a) to 4(b), a straight line extending in the x direction passing through the optical axis 420 of the lens 42 and a straight line extending in the y direction passing through the optical axis 420 of the lens 42 are indicated by dashed lines. Hereinafter, the straight line extending in the x direction passing through the optical axis 420 of the lens 42 is denoted as the first straight line Lx, and the straight line extending in the y direction passing through the optical axis 420 of the lens 42 is denoted as the second straight line Ly. Also, hereinafter, the four regions into which the lens 42 is divided by the first straight line Lx and the second straight line Ly are denoted as the first region 421, the second region 422, the third region 423, and the fourth region 424, respectively. The first region 421 is a region of the lens 42 on the +y direction side of the first straight line Lx and on the -x direction side of the second straight line Ly. The second region 422 is a region of the lens 42 on the +y direction side of the first straight line Lx and on the +x direction side of the second straight line Ly. The third region 423 is a region of the lens 42 on the -y direction side of the first straight line Lx and on the -x direction side of the second straight line Ly. The fourth region 424 is a region of the lens 42 on the -y direction side of the first straight line Lx and on the +x direction side of the second straight line Ly.

[0023] The lens 42 has a circular shape centered on the optical axis 420 when viewed along the z direction. And the lens 42 has axisymmetric optical characteristics centered on the optical axis 420. More specifically, the lens 42 refracts the light incident along the +z direction in a direction approaching the optical axis 420. That is, the lens 42 refracts the light incident on the first region 421 in the +x direction and the -y direction. Also, the lens 42 refracts the light incident on the second region 422 in the -x direction and the -y direction. Also, the lens 42 refracts the light incident on the third region 423 in the +x direction and the +y direction. Also, the lens 42 refracts the light incident on the fourth region 424 in the -x direction and the +y direction. Further, the lens 42 has an optical characteristic of refracting the light incident along the radial direction from the optical axis 420 toward the circumference more greatly. Note that the lens 42 does not refract the light incident on the optical axis 420.

[0024] As described above, the light sources 4A and 4B have different positions of the light-emitting chip 41 with respect to the lens 42. As shown in FIG. 4(a), in the light source 4A, the light-emitting chip 41 and the lens 42 are arranged such that the light-emitting surface 411 faces the first region 421 and the second region 422 of the lens 42. Specifically, in the light source 4A, the light-emitting chip 41 and the lens 42 are arranged such that the center 411C of the light-emitting surface 411 is displaced in the +y direction with respect to the optical axis 420 of the lens 42. Also, in the light source 4A, the light-emitting chip 41 and the lens 42 are arranged such that the center 411C of the light-emitting surface 411 is located on the second straight line Ly of the lens 42. Further, in the light source 4A, the light-emitting chip 41 and the lens 42 are arranged such that the long side 411x located on the -y direction side of the light-emitting surface 411 overlaps the first straight line Lx of the lens 42.

[0025] Also, in the light source 4B, the light-emitting chip 41 and the lens 42 are arranged such that the position of the light-emitting surface 412 with respect to the lens 42 is symmetric to the position of the light-emitting surface 411 with respect to the lens 42 in the light source 4A with the first straight line Lx of the lens 42 as the axis of symmetry. That is, as shown in FIG. 4(b), in the light source 4B, the light-emitting chip 41 and the lens 42 are arranged such that the light-emitting surface 412 faces the third region 423 and the fourth region 424 of the lens 42. Specifically, in the light source 4B, the light-emitting chip 41 and the lens 42 are arranged such that the center 412C of the light-emitting surface 412 is displaced in the -y direction with respect to the optical axis 420 of the lens 42. Also, in the light source 4B, the light-emitting chip 41 and the lens 42 are arranged such that the center 412C of the light-emitting surface 412 is located on the second straight line Ly of the lens 42. Further, in the light source 4B, the light-emitting chip 41 and the lens 42 are arranged such that the long side 412x located on the +y direction side of the light-emitting surface 412 overlaps the first straight line Lx of the lens 42.

[0026] In the light-emitting unit 4 of the present embodiment, the light-emitting surface 411 of the light-emitting chip 41 in the light source 4A and the light-emitting surface 412 of the light-emitting chip 41 in the light source 4B overlap with the first straight line Lx of the respective lenses 42. As a result, there is no gap in the relative positions of the light-emitting surface 411 and the light-emitting surface 412 with respect to the lens 42. Note that in the light-emitting unit 4 of the present embodiment, the relative positions of the light-emitting surface 411 and the light-emitting surface 412 with respect to the lens 42 overlap only at the first straight line Lx of the lens 42, but it is not limited to this. For example, by displacing the light-emitting surface 411 to the -y direction side from that in FIG. 4(a) and the light-emitting surface 412 to the +y direction side from that in FIG. 4(b), in the present embodiment, the relative positions of the light-emitting surface 411 and the light-emitting surface 412 with respect to the lens 42 may overlap in the first region 421 to the fourth region 424 of the lens 42.

[0027] (Light irradiation area by the light-emitting unit 4) FIG. 5 is a diagram for explaining the relationship between the irradiation area 100A irradiated with the light emitted from the light source 4A of the light-emitting unit 4 and the irradiation area 100B irradiated with the light emitted from the light source 4B. FIG. 5 is a view of the light-emitting unit 4 and the irradiation areas 100A and 100B as seen from the +x direction side to the -x direction. Subsequently, with reference to FIG. 5 and FIGS. 2 to 4 described above, the relationship between the irradiation area 100A irradiated with the light emitted from the light source 4A and the irradiation area 100B irradiated with the light emitted from the light source 4B will be described.

[0028] In the light source 4A, the light emitted from the light-emitting surface 411 of the light-emitting chip 41 enters the first straight line Lx of the lens 42 and the first region 421 and the second region 422 on the +y direction side of the first straight line Lx. In this example, the light emitted from the light-emitting surface 411 enters the lens 42 along the +z direction. Then, the light incident on the lens 42 from the light emitting surface 411 is refracted in a direction approaching the optical axis 420 due to the optical characteristics of the lens 42. Specifically, the light incident on the first region 421 of the lens 42 from the light emitting surface 411 is refracted in the +x direction and the -y direction. Also, the light incident on the second region 422 of the lens 42 from the light emitting surface 411 is refracted in the -x direction and the -y direction. Then, the light refracted by the lens 42 is emitted from the light source 4A.

[0029] In the light source 4B, the light emitted from the light emitting surface 412 of the light emitting chip 41 is incident on the first straight line Lx of the lens 42, and the third region 423 and the fourth region 424 on the -y direction side of the first straight line Lx. In this example, the light emitted from the light emitting surface 412 is incident on the lens 42 in the +z direction. Then, the light incident on the lens 42 from the light emitting surface 412 is refracted in a direction approaching the optical axis 420 due to the optical characteristics of the lens 42. Specifically, the light incident on the third region 423 of the lens 42 from the light emitting surface 412 is refracted in the +x direction and the +y direction. Also, the light incident on the fourth region 424 of the lens 42 from the light emitting surface 412 is refracted in the -x direction and the +y direction. Then, the light refracted by the lens 42 is emitted from the light source 4B.

[0030] As described above, the lens 42 has an optical characteristic of refracting the incident light more greatly as it goes circumferentially along the radial direction from the optical axis 420. Thereby, the irradiation region 100A irradiated with the light emitted from the light source 4A expands in the ±x direction and the -y direction as it goes in the +z direction. And the center line 101A of the irradiation region 100A inclines toward the -y direction side as it goes in the +z direction. Also, the irradiation region 100B irradiated with the light emitted from the light source 4B expands in the ±x direction and the +y direction as it goes in the +z direction. And the center line 101B of the irradiation region 100B inclines toward the +y direction side as it goes in the +z direction.

[0031] In the light-emitting unit 4 of the present embodiment, as shown in FIGS. 3 and 5, the center line 101A of the light irradiated from the light source 4A to the irradiation region 100A and the center line 101B of the light irradiated from the light source 4B to the irradiation region 100B intersect. Here, in the present embodiment, the fact that the center line 101A of the irradiation region 100A and the center line 101B of the irradiation region 100B intersect means that when the irradiation regions 100A and 100B are viewed along one direction (in this example, the x direction) intersecting in the z direction, the center line 101A and the center line 101B have an intersection point. Hereinafter, the intersection point of the center line 101A and the center line 101B will be denoted as the intersection portion 102. Further, the center line 101A of the irradiation region 100A is a line connecting the centers of the irradiation surfaces irradiated with the light emitted from the light-emitting unit 4 and irradiated with the light from the light source 4A. Similarly, the center line 101B of the irradiation region 100B is a line connecting the centers of the irradiation surfaces irradiated with the light emitted from the light-emitting unit 4 and irradiated with the light from the light source 4B.

[0032] In the present embodiment, on the -z direction side of the intersection portion 102, the irradiation regions 100A and 100B are arranged in the -y direction. Also, on the +z direction side of the intersection portion 102, the irradiation regions 100A and 100B are arranged in the +y direction. In other words, on the -z direction side and the +z direction side of the intersection portion 102, the arrangement of the irradiation regions 100A and 100B is reversed. Furthermore, on the +z direction side of the intersection portion 102, the arrangement of the irradiation regions 100A and 100B is reversed from the arrangement of the light sources 4A and 4B.

[0033] Note that in the light-emitting unit 4 of the present embodiment, the intersection portion 102 is located inside the housing 44. The reason for this will be described in detail later.

[0034] Further, in the present embodiment, a non-irradiation region 100X where the light emitted from the light sources 4A and 4B is not irradiated is formed between the irradiation region 100A and the irradiation region 100B on the -z direction side of the intersection 102. In this example, as shown in FIG. 5, the non-irradiation region 100X is formed in the range from the light sources 4A and 4B to a certain distance on the -z direction side of the intersection 102.

[0035] When irradiating different irradiation regions with light by a plurality of light sources as in the light emitting unit 4 of the present embodiment, there may be a case where a non-irradiation region where light is not irradiated is formed between the irradiation regions irradiated with the light from each light source. And depending on the positional relationship of the plurality of light sources and the direction of the light emitted from each light source, etc., a non-irradiation region may be formed in a wide range in the +z direction from the light source. For example, when irradiating different irradiation regions with light by a plurality of light sources so that the center lines of the irradiation regions do not intersect, a non-irradiation region is likely to be formed in a wide range in the +z direction from the light source. In the non-irradiation region, since the light from the light source is not irradiated onto the object, distance measurement of the object cannot be performed based on the light reflected by the object.

[0036] On the other hand, in the light emitting unit 4 of the present embodiment, by irradiating the light sources 4A and 4B so that the center line 101A of the irradiation region 100A and the center line 101B of the irradiation region 100B intersect, a non-irradiation region 100X is not formed on the +z direction side of the intersection 102. Thereby, in the light emitting unit 4 of the present embodiment, compared with the case of irradiating light by a plurality of light sources so that the center lines of the irradiation regions do not intersect, the range in which the non-irradiation region 100X is formed can be narrowed.

[0037] Further, in the light emitting unit 4 of the present embodiment, the non-irradiation region 100X is located inside the housing 44. Thereby, entry of an object to be distance-measured into the non-irradiation region 100X where distance measurement of the object cannot be performed is suppressed.

[0038] The irradiation surface is a surface irradiated with the light from the light emitting unit 4 orthogonal to the z direction at a certain distance in the z direction of the irradiation regions 100A and 100B irradiated with the light emitted from the light sources 4A and 4B of the light emitting unit 4. FIG. 5 shows irradiation surfaces 210, 220, and 230 arranged in order in a direction away from the light sources 4A and 4B of the light emitting unit 4 in the +z direction as the irradiation surfaces. The irradiation surfaces 210, 220, and 230 extend in the x direction and the y direction at a certain distance in the +z direction. Further, the irradiation surfaces 210, 220, and 230 are located on the +z direction side of the intersection portion 102 where the center line 101A of the irradiation region 100A and the center line 101B of the irradiation region 100B intersect. Furthermore, the irradiation surface 210 is located inside the housing 44, and the irradiation surfaces 220 and 230 are located outside the housing 44.

[0039] FIGS. 6(a) to 6(c) are views of the irradiation surfaces 210, 220, and 230 as seen from the -z direction side to the +z direction. In the light sources 4A and 4B (see FIG. 3) of the present embodiment, as described above, the irradiation range of the light emitted from the light emitting chip 41 is expanded in the +z direction by the lens 42. Therefore, the area of each irradiation surface increases in the order of the irradiation surface 210, the irradiation surface 220, and the irradiation surface 230 arranged in the +z direction.

[0040] The irradiation surface 210 includes an irradiation surface 211 irradiated with light from the light source 4A and an irradiation surface 212 irradiated with light from the light source 4B. In the irradiation surface 210, the irradiation surface 211 and the irradiation surface 212 are arranged in the y direction. In this example, the irradiation surface 211 is located on the -y direction side with respect to the irradiation surface 212. That is, the arrangement of the light sources 4A and 4B in the light emitting unit 4 and the arrangement of the irradiation surfaces 211 and 212 in the irradiation surface 210 are inverted. Further, an overlapping region 213 is formed on the irradiation surface 210 where a partial region in the y direction of the irradiation surface 211 and the irradiation surface 212 overlaps. In other words, an overlapping region 213 is formed on the irradiation surface 210 where a partial region on the +y direction side of the irradiation surface 211 and a partial region on the -y direction side of the irradiation surface 212 overlap.

[0041] Similarly, the irradiation surface 220 includes an irradiation surface 221 irradiated with light from the light source 4A and an irradiation surface 222 irradiated with light from the light source 4B. On the irradiation surface 220, the irradiation surface 221 and the irradiation surface 222 are arranged side by side in the y direction. In this example, the irradiation surface 221 is located on the -y direction side with respect to the irradiation surface 222. That is, the arrangement of the light sources 4A and 4B in the light emitting unit 4 and the arrangement of the irradiation surfaces 221 and 222 on the irradiation surface 220 are inverted. In addition, an overlapping region 223 in which a part of the regions of the irradiation surface 221 and the irradiation surface 222 overlap in the y direction is formed on the irradiation surface 220. Specifically, on the irradiation surface 220, an overlapping region 223 is formed in which a part of the region on the +y direction side of the irradiation surface 221 and a part of the region on the -y direction side of the irradiation surface 222 overlap.

[0042] Similarly, the irradiation surface 230 includes an irradiation surface 231 irradiated with light from the light source 4A and an irradiation surface 232 irradiated with light from the light source 4B. On the irradiation surface 230, the irradiation surface 231 and the irradiation surface 232 are arranged side by side in the y direction. In this example, the irradiation surface 231 is located on the -y direction side with respect to the irradiation surface 232. That is, the arrangement of the light sources 4A and 4B in the light emitting unit 4 and the arrangement of the irradiation surfaces 231 and 232 on the irradiation surface 230 are inverted. In addition, an overlapping region 233 in which a part of the regions of the irradiation surface 231 and the irradiation surface 232 overlap in the y direction is formed on the irradiation surface 230. Specifically, on the irradiation surface 230, an overlapping region 233 is formed in which a part of the region on the +y direction side of the irradiation surface 231 and a part of the region on the -y direction side of the irradiation surface 232 overlap.

[0043] On the irradiation surfaces 210, 220, and 230, the overlap between the irradiation surfaces 211, 221, 231 irradiated with light from the light source A and the irradiation surfaces 212, 222, 232 irradiated with light from the light source 4B decreases as the distance from the light sources 4A and 4B in the +z direction increases. Although not shown in the figure, there is a certain distance from the light sources 4A and 4B in the +z direction at which the overlapping region is no longer formed between the irradiation surface irradiated with light from the light source 4A and the irradiation surface irradiated with light from the light source 4B. As a result, the ratio of the area of the overlapping regions 213, 223, 233 to the area of the irradiation surfaces 210, 220, 230 decreases as the distance from the light sources 4A, 4B increases. Specifically, the ratio of the area of the overlapping region 223 to the area of the irradiation surface 220 is smaller than the ratio of the area of the overlapping region 213 to the area of the irradiation surface 210. Also, the ratio of the area of the overlapping region 233 to the area of the irradiation surface 230 is smaller than the ratio of the area of the overlapping region 223 to the area of the irradiation surface 220.

[0044] Also, on the irradiation surface 210, the area of the overlapping region 213 is larger than the sum of the areas of the irradiation surface 211 excluding the overlapping region 213 and the irradiation surface 212 excluding the overlapping region 213. On the other hand, on the irradiation surface 220, the area of the overlapping region 223 is smaller than the sum of the areas of the irradiation surface 221 excluding the overlapping region 223 and the irradiation surface 222 excluding the overlapping region 223. Similarly, on the irradiation surface 230, the area of the overlapping region 233 is smaller than the sum of the areas of the irradiation surface 231 excluding the overlapping region 233 and the irradiation surface 232 excluding the overlapping region 233.

[0045] Thus, on the irradiation surfaces located on the +z direction side of the intersection 102, the closer to the intersection 102, the higher the ratio of the area of the overlapping region to the area of the irradiation surface. And when the light sources 4A and 4B are lit simultaneously, in the overlapping region, since the light from the light source 4A and the light from the light source 4B are irradiated, the amount of light irradiated is larger than that in the regions other than the overlapping region. When an object enters the overlapping region close to the intersection 102, the amount of light irradiated to the object may become excessive. And the amount of light received by the light receiving element of the light receiving unit 5 that receives the light reflected by the object may become excessive, and signal saturation may occur. In this case, it becomes difficult to measure the distance to the object. Also, when the object is a person, there may be a problem with eye safety due to the excessive amount of irradiated light.

[0046] In contrast, in the light emitting unit 4 of the present embodiment, the intersection portion 102 is located inside the housing 44. Thereby, entry of an object into an overlapping area that is close to the intersection portion 102 is suppressed. In the examples shown in FIGS. 3 and 5, entry of an object into the overlapping area 213 of the irradiation surface 210 that is close to the intersection portion 102 is suppressed. As a result, an excessive amount of light irradiated onto the object is suppressed.

[0047] (Light receiving unit 5) The light receiving unit 5 includes a light receiving surface that extends in the x direction and the y direction and in which a plurality of light receiving elements are arranged. Then, the light receiving unit 5 receives, by each light receiving element, light emitted from the light emitting unit 4 and reflected by the object. The light receiving surface is divided into a plurality of light receiving sections corresponding to the plurality of light sources 4A and 4B of the light emitting unit 4. In the light receiving unit 5 of the present embodiment, the light receiving surface is divided into two light receiving sections in the y direction. Each light receiving section has a plurality of regularly arranged light receiving elements. Each light receiving element receives light emitted from the light sources 4A and 4B of the light emitting unit 4 and reflected by the object, and outputs an electrical signal according to the received light. Examples of the light receiving element include a photodiode and a phototransistor.

[0048] Each light receiving element of the light receiving unit 5 of the present embodiment receives light reflected by the object at a position farther from the light emitting unit 4 than the intersection portion 102 where the center line 101A of the irradiation area 100A and the center line 101B of the irradiation area 100B intersect.

[0049] Each light receiving section is independently driven by a light receiving driving unit 7 (see FIG. 1) to perform a light receiving operation. Driving of the light receiving section refers to changing the light receiving elements included in the light receiving section from a state where light cannot be received to a state where light can be received and an electrical signal can be output. Also, "independently driven" refers to being driven for each light receiving section to change to a state where light can be received and an electrical signal can be output. The light receiving driving unit 7 drives each light receiving section according to a control signal from a control unit 8 (see FIG. 1). Then, when the light-receiving elements included in each light-receiving section receive light, they output an electrical signal corresponding to the received light to the control unit 8.

[0050] [Embodiment 2] In the light-emitting unit 4, the light-emitting surfaces 411 of the light-emitting chips 41 included in the light source 4A and the light-emitting surfaces 412 of the light-emitting chips 41 included in the light source 4B may be divided into a plurality of light-emitting sections. Hereinafter, as Embodiment 2 of the present invention, an aspect in which the light-emitting surfaces 411 and 412 are divided into a plurality of light-emitting sections will be described. For the same configurations as those in the above-described Embodiment 1, the same reference numerals are used, and detailed descriptions thereof are omitted here.

[0051] (Light-emitting surfaces 411, 412) FIGS. 7(a) to 7(b) are diagrams for explaining the light-emitting surface 411 of the light source 4A and the light-emitting surface 412 of the light source 4B to which the present embodiment is applied. FIG. 7(a) shows the light-emitting surface 411 of the light-emitting chip 41 included in the light source 4A, and FIG. 7(b) shows the light-emitting surface 412 of the light-emitting chip 41 included in the light source 4B. FIGS. 7(a) to 7(b) correspond to views of the light-emitting surfaces 411 and 412 as viewed from the -z direction side to the +z direction.

[0052] The light-emitting surface 411 of the light source 4A in FIG. 7(a) is divided into a plurality of light-emitting sections 411A each including at least one VCSEL 45. In this example, the light-emitting surface 411 is divided into a total of 16 light-emitting sections 411A arranged in 4 rows in the x direction and 4 rows in the y direction as an example. As shown in the figure, when it is necessary to distinguish each light-emitting section 411A, they are distinguished as light-emitting sections A1 to A16 in order from the upper left side (-x direction and +y direction ends) in FIG. 7(a). In the present specification, "~" indicates a plurality of components distinguished by numbers, and means including those described before and after "~" and those with numbers in between. For example, the light-emitting sections A1 to A16 include 16 light-emitting sections 411A from the light-emitting section A1 to the light-emitting section A16 in order of number.

[0053] The light emitting surface 412 of the light source 4B in FIG. 7(b) is divided into a plurality of light emitting sections 412B each including at least one VCSEL 45. In this example, the light emitting surface 412 is divided into a total of 16 light emitting sections 412B arranged in 4 in the x direction and 4 in the y direction as an example. As shown in the figure, when it is necessary to distinguish each light emitting section 412B, they are distinguished as light emitting sections B1 to B16 in order from the upper left side (-x direction and +y direction ends) in FIG. 7(b).

[0054] Each light emitting section 411A of the light source 4A and each light emitting section 412B of the light source 4B are independently driven by a light emission driving unit 6 (see FIG. 1) to perform a light emission operation. The light emission driving unit 6 drives each light emitting section 411A of the light source 4A and each light emitting section 412B of the light source 4B according to a control signal from a control unit 8 (see FIG. 1). Therefore, each light emitting section 411A of the light source 4A does not necessarily emit light all at the same time. For example, in the example of FIG. 7(a), a state where the light emitting section A1 is emitting light but the light emitting section A16 is not emitting light can be taken. Similarly, each light emitting section 412B of the light source 4B does not necessarily emit light all at the same time. For example, in the example of FIG. 7(b), a state where the light emitting section B1 is emitting light but the light emitting section B16 is not emitting light can be taken.

[0055] FIG. 8 is a diagram showing an example of an irradiation surface 310 irradiated with light emitted from the light source 4A having the light emitting surface 411 shown in FIG. 7(a) and the light source 4B having the light emitting surface 412 shown in FIG. 7(b). Incidentally, FIG. 8 is a view of the irradiation surface 310 seen in the +z direction. FIG. 8 shows an irradiation surface 310 such that the distances in the z direction from the light sources 4A and 4B are the same as those of the irradiation surface 230 shown in FIG. 5. The irradiation surface 310 includes an irradiation surface 311 irradiated with light from the light source 4A and an irradiation surface 312 irradiated with light from the light source 4B. On the irradiation surface 310, the irradiation surface 311 and the irradiation surface 312 are arranged side by side in the y direction. Further, on the irradiation surface 310, an overlapping region 313 is formed where a part of the region on the +y direction side of the irradiation surface 311 and a part of the region on the -y direction side of the irradiation surface 312 overlap each other.

[0056] The irradiation surface 311 is divided into a plurality of irradiation sections 311C corresponding to the light-emitting sections 411A on the light-emitting surface 411. In the example of FIG. 8, the irradiation surface 311 is divided into a total of 16 irradiation sections 311C arranged in 4 rows in the x direction and 4 rows in the y direction. When it is necessary to distinguish each irradiation section 311C of the irradiation surface 311, it is denoted as irradiation sections C1 to C16. In this example, the light emitted from a certain light-emitting section Ai is irradiated onto the irradiation section Ci given the same number i. Hereinafter, a light-emitting section Ai given the same number as a certain irradiation section Ci may be referred to as the "corresponding light-emitting section". Conversely, an irradiation section Ci given the same number i as a certain light-emitting section Ai may be referred to as the "corresponding irradiation section". The same applies to the irradiation surface 312 described below.

[0057] The light emitted from each of the light-emitting sections A1 to A16 on the light-emitting surface 411 is refracted by the lens 42 (see FIG. 3) and irradiated onto the irradiation surface 311. As a result, on the irradiation surface 311, the irradiation sections C1 to C16 are arranged in order from the lower right side (+x direction and -y direction end) in FIG. 8. Additionally, the order in which the irradiation sections C1 to C16 are arranged on the irradiation surface 311 is inverted in the x direction and the y direction with respect to the order in which the light-emitting sections A1 to A16 are arranged on the light-emitting surface 411.

[0058] Similarly, the irradiation surface 312 is divided into a plurality of irradiation sections 312D corresponding to the light-emitting sections 412B on the light-emitting surface 412. In the example of FIG. 8, the irradiation surface 312 is divided into a total of 16 irradiation sections 312D arranged in 4 rows in the x direction and 4 rows in the y direction. When it is necessary to distinguish each irradiation section 312D, it is denoted as irradiation sections D1 to D16. The light emitted from each of the light-emitting sections B1 to B16 on the light-emitting surface 412 is refracted by the lens 42 and irradiated onto the irradiation surface 312. As a result, on the irradiation surface 312, the irradiation sections D1 to D16 are arranged in order from the lower right side (+x direction and -y direction end) in FIG. 8. Additionally, the order in which the irradiation sections D1 to D16 are arranged on the irradiation surface 312 is inverted in the x direction and the y direction with respect to the order in which the light-emitting sections B1 to B16 are arranged on the light-emitting surface 412.

[0059] On the irradiation surface 310, the irradiation section C13 of the irradiation surface 311 and the irradiation section D1 of the irradiation surface 312 are adjacent to each other in the y direction. Also, the irradiation section C14 of the irradiation surface 311 and the irradiation section D2 of the irradiation surface 312 are adjacent to each other in the y direction. Also, the irradiation section 15 of the irradiation surface 311 and the irradiation section D3 of the irradiation surface 312 are adjacent to each other in the y direction. Also, the irradiation section C16 of the irradiation surface 311 and the irradiation section D4 of the irradiation surface 312 are adjacent to each other in the y direction.

[0060] As described above, an overlapping region 313 is formed on the irradiation surface 310. The overlapping region 313 includes an overlapping portion E1 where a part of the region on the +y direction side in the irradiation section C13 of the irradiation surface 311 overlaps with a part of the region on the -y direction side in the irradiation section D1 of the irradiation surface 312. Also, the overlapping region 313 includes an overlapping portion E2 where a part of the region on the +y direction side in the irradiation section C14 of the irradiation surface 311 overlaps with a part of the region on the -y direction side in the irradiation section D2 of the irradiation surface 312. Also, the overlapping region 313 includes an overlapping portion E3 where a part of the region on the +y direction side in the irradiation section C15 of the irradiation surface 311 overlaps with a part of the region on the -y direction side in the irradiation section D3 of the irradiation surface 312. Also, the overlapping region 313 includes an overlapping portion E4 where a part of the region on the +y direction side in the irradiation section C16 of the irradiation surface 311 overlaps with a part of the region on the -y direction side in the irradiation section D4 of the irradiation surface 312. The overlapping portions E1 to E4 are arranged in the -x direction.

[0061] (Light receiving unit 5) Similar to the above-described Embodiment 1, the light receiving unit 5 has a light receiving surface that extends in the x direction and the y direction and on which a plurality of light receiving elements are arranged. The light receiving surface is divided into a plurality of light receiving sections corresponding to the irradiation sections C1 to C16 of the irradiation surface 311 irradiated with light from the light emitting sections A1 to A16 of the light source 4A and the irradiation sections D1 to D16 of the irradiation surface 312 irradiated with light from the light emitting sections B1 to B16 of the light source 4B. That is, the light receiving surface includes 16 light receiving sections arranged in 4 rows in the x direction and 4 rows in the y direction corresponding to the irradiation sections C1 to C16, and 16 light receiving sections arranged in 4 rows in the x direction and 4 rows in the y direction corresponding to the irradiation sections D1 to D16. Each light-receiving section receives light that is emitted from the light sources 4A and 4B of the light-emitting section 4 and is reflected by an object existing in the corresponding irradiation section of the irradiation surfaces 311 and 312. Each light-receiving section of the light-receiving section 5 is independently driven by a light-receiving driving section 7 (see FIG. 1) to perform a light-receiving operation.

[0062] (Operation of the light-emitting section 4) Next, the operation of the light-emitting section 4 driven by the light-emitting driving section 6 under the control of the control section 8 will be described. In the light-emitting section 4, when the irradiation sections of the light source 4A and the irradiation section of the light source 4B that irradiate light on the overlapping region 313 are lit simultaneously, the overlapping region 313 is irradiated with light from the irradiation section of the light source 4A and light from the irradiation section of the light source 4B. In this case, compared with the region other than the overlapping region of the irradiation surface 310, the amount of light irradiated on the overlapping region 313 increases. As a result, the amount of light irradiated on the irradiation surface 310 becomes non-uniform between the overlapping region 313 and the region other than the overlapping region 313. On the other hand, the control section 8 of the present embodiment does not simultaneously light the light-emitting section of the light source 4A and the light-emitting section of the light source 4B that irradiate light on the irradiation sections forming the overlapping region 313. In other words, the light-emitting section of the light source 4A and the light-emitting section of the light source 4B that irradiate light on the adjacent irradiation sections on the irradiation surfaces 311 and 312 are not lit simultaneously.

[0063] More specifically, the control section 8 does not simultaneously light the light-emitting section A13 of the light source 4A that irradiates light on the irradiation section C13 forming the overlapping portion E1 of the overlapping region 313 and the light-emitting section B1 of the light source 4B that irradiates light on the irradiation section D1 forming the overlapping portion E1. Further, the control section 8 does not simultaneously light the light-emitting section A14 of the light source 4A that irradiates light on the irradiation section C14 forming the overlapping portion E2 of the overlapping region 313 and the light-emitting section B2 of the light source 4B that irradiates light on the irradiation section D2 forming the overlapping portion E2. Further, the control section 8 does not simultaneously light the light-emitting section A15 of the light source 4A that irradiates light on the irradiation section C15 forming the overlapping portion E3 of the overlapping region 313 and the light-emitting section B3 of the light source 4B that irradiates light on the irradiation section D3 forming the overlapping portion E3. Further, the control unit 8 does not simultaneously turn on the light-emitting section A16 of the light source 4A that irradiates light onto the irradiation section C16 forming the overlapping section E4 of the overlapping region 313 and the light-emitting section B4 of the light source 4B that irradiates light onto the irradiation section D4 forming the overlapping section E4.

[0064] The control unit 8 of the present embodiment turns on all of the light-emitting sections A1 to A16 of the light source 4A and the light-emitting sections B1 to B16 of the light source 4B while not simultaneously turning on the light-emitting section of the light source 4A and the light-emitting section of the light source 4B that irradiate light onto the irradiation sections forming the overlapping region 313. In other words, the control unit 8 turns on the light-emitting sections A1 to A16 of the light source 4A and the light-emitting sections B1 to B16 of the light source 4B by turning on the light-emitting section of the light source 4A and the light-emitting section of the light source 4B that irradiate light onto the irradiation sections forming the overlapping region 313 at different times. As a result, all of the irradiation sections C1 to C16 of the irradiation surface 311 and all of the irradiation sections D1 to D16 of the irradiation surface 312 are irradiated with light, and the entire irradiation surface 310 is irradiated with light without any gaps. Here, as long as the light-emitting section of the light source 4A and the light-emitting section of the light source 4B that irradiate light onto the irradiation sections forming the overlapping region 313 are not simultaneously turned on, the order in which the light-emitting sections A1 to A16 of the light source 4A and the light-emitting sections B1 to B16 of the light source 4B are turned on is not limited.

[0065] Figs. 9(a) to (b) are diagrams for explaining the order in which the control unit 8 turns on the light-emitting sections A1 to A16 of the light source 4A and the light-emitting sections B1 to B16 of the light source 4B to irradiate light onto the irradiation sections C1 to C16 and the irradiation sections D1 to D16 of the irradiation surface 310. Figs. 9(a) to (b) are views of the irradiation surface 310 seen in the +z direction, similar to Fig. 8. In Figs. 9(a) to (b), the hatched irradiation sections are the irradiation sections irradiated with light by the light-emitting sections turned on by the control unit 8.

[0066] The control unit 8 may sequentially light up the light-emitting sections A1 to A16 of the light source 4A and the light-emitting sections B1 to B16 of the light source 4B one by one. In this example, after lighting up the light-emitting sections B1 to B16 of the light source 4B, the control unit 8 then sequentially lights up the light-emitting sections A1 to A16 of the light source 4A. In other words, in this example, the light-emitting sections A1 to A16 of the light source 4A and the light-emitting sections B1 to B16 of the light source 4B are not lit up simultaneously. Specifically, as shown in FIG. 9(a), the control unit 8 sequentially lights up the light-emitting sections B16 to B1 of the light source 4B so that light is sequentially irradiated from the light-emitting section D16 located at the upper left of the irradiation surface 312 to the light-emitting section D1 located at the lower right. Subsequently, the control unit 8 sequentially lights up the light-emitting sections A16 to A1 of the light source 4A so that light is sequentially irradiated from the light-emitting section C16 located at the upper left of the irradiation surface 311 to the light-emitting section C1 located at the lower right. Thereby, all the irradiation sections C1 to C16 and D1 to D16 on the irradiation surface 310 are irradiated with light.

[0067] Also, as long as the control unit 8 does not simultaneously light up the light-emitting section of the light source 4A and the light-emitting section of the light source 4B that irradiate light to the irradiation section forming the overlapping region 313, any light-emitting section of the light source 4A and any light-emitting section of the light source 4B may be simultaneously lit up. In the example shown in FIG. 9(b), the control unit 8 lights up the light-emitting section B1 of the light source 4B that irradiates light to the overlapping portion E1 of the overlapping region 313, and does not light up the light-emitting section A13 of the light source 4A that irradiates light to the overlapping portion E1. Also, the control unit 8 lights up the light-emitting section B2 of the light source 4B that irradiates light to the overlapping portion E2 of the overlapping region 313, and does not light up the light-emitting section A14 of the light source 4A that irradiates light to the overlapping portion E2. Furthermore, the control unit 8 lights up the light-emitting section A15 of the light source 4A that irradiates light to the overlapping portion E3 of the overlapping region 313, and does not light up the light-emitting section B3 of the light source 4B that irradiates light to the overlapping portion E3. Also, the control unit 8 lights up the light-emitting section A16 of the light source 4A that irradiates light to the overlapping portion E4 of the overlapping region 313, and does not light up the light-emitting section B4 of the light source 4B that irradiates light to the overlapping portion E4.

[0068] In this example, the light-emitting sections A15 and A16 of the light source 4A that are lit to irradiate light, the irradiation sections C15 and C16, and the light-emitting sections B1 and B2 of the light source 4B that are lit to irradiate light, the irradiation sections D1 and D2, are an example of the first irradiation section. Also, the irradiation sections C13 and C14 where the light-emitting sections A13 and A14 of the light source 4A are not lit and no light is irradiated, and the irradiation sections D3 and D4 where the light-emitting sections B3 and B4 of the light source 4B are not lit and no light is irradiated, are an example of the second irradiation section.

[0069] And in the example shown in FIG. 9(b), the control unit 8 simultaneously lights the light-emitting section of the light source 4A that irradiates light to the irradiation section that does not form the overlapping region 313 of the irradiation surface 311, and the light-emitting section that irradiates light to the irradiation section that does not form the overlapping region 313 of the irradiation surface 312. More specifically, the control unit 8 simultaneously lights the light-emitting sections A1, A2, A5, A6, A11, and A12 of the light source 4A that irradiate light to the irradiation sections C1, C2, C5, C6, C11, and C12 of the irradiation surface 311. Also, the control unit 8 simultaneously lights the light-emitting sections B5, B6, B11, B12, B15, and B16 of the light source 4B that irradiate light to the irradiation sections D5, D6, D11, D12, D15, and D16 of the irradiation surface 312.

[0070] Then, after the control unit 8 simultaneously lights the light-emitting sections A1, A2, A5, A6, A11, A12, A15, and A16 of the light source 4A and the light-emitting sections B1, B2, B5, B6, B11, B12, B15, and B16 of the light source 4B, it turns off these light-emitting sections. Then, it simultaneously lights the remaining light-emitting sections A3, A4, A7 to A10, A13, and A14 of the light source 4A and the remaining light-emitting sections B3, B4, B7 to B10, B13, and B14 of the light source 4B. Thereby, all the irradiation sections C1 to C16 and D1 to D16 of the irradiation surface 310 are irradiated with light.

[0071] As described above, in this embodiment, when the light-emitting section of one light source that irradiates light onto the first irradiation section that forms the overlapping region 313 of the irradiation surface 310 is turned on, and the light-emitting section of the other light source that irradiates light onto the second irradiation section that forms the overlapping region 313 is not turned on, the light-emitting sections that irradiate light onto the other irradiation sections other than the first irradiation section and the second irradiation section are simultaneously turned on. As a result, for example, compared with the case where the light-emitting sections that irradiate light onto the other irradiation sections other than the first irradiation section and the second irradiation section are not simultaneously turned on, the time required until light is irradiated onto all the irradiation sections of the irradiation surface 310 can be shortened.

[0072] [Embodiment 3] In the above-described Embodiment 1 and Embodiment 2, the case where the light-emitting section 4 has two light sources 4A and 4B as a plurality of light sources has been described as an example. However, the light-emitting section 4 may have three or more light sources as a plurality of light sources. Hereinafter, as Embodiment 3 of the present invention, an aspect in which the light-emitting section 4 has four light sources 4K, 4L, 4M, and 4N will be described. Note that the same reference numerals are used for the same configurations as those in the above-described Embodiment 1 and Embodiment 2, and detailed descriptions thereof are omitted here.

[0073] Figs. 10(a) to 10(b) are diagrams showing the relationship between the light sources 4K to 4N of the light-emitting section 4 of this embodiment and the irradiation regions 100K to 100N irradiated with the light emitted from the respective light sources 4K to 4N. In Figs. 10(a) to 10(b), as the irradiation regions 100K to 100N, cross-sections obtained by cutting the irradiation regions 100K to 100N with a plane orthogonal to the z direction at a certain distance in the z direction are shown. Figs. 10(a) to 10(b) correspond to views of the light sources 4K to 4N and the irradiation regions 100K to 100N as seen from the -z direction side to the +z direction. In Figs. 10(a) to 10(b), the light sources 4K to 4N and the irradiation regions 100K to 100N are shown shifted in the vertical direction (y direction) of the paper surface, but actually, the light sources 4K to 4N and the irradiation regions 100K to 100N are arranged to face each other in the z direction. In Figs. 10(a) to 10(b), the light sources 4K to 4N are located in the front side direction (-z direction) of the paper surface, and the irradiation regions 100K to 100N are located in the back side direction (+z direction) of the paper surface. Although details will be described later, in FIGS. 10(a) and 10(b), the relationship between the arrangement of the light sources 4K to 4N and the arrangement of the irradiation regions 100K to 100N are different from each other.

[0074] The light emitting unit 4 of the present embodiment includes a light source 4K that irradiates the irradiation region 100K with light, a light source 4L that irradiates the irradiation region 100L with light, a light source 4M that irradiates the irradiation region 100M with light, and a light source 4N that irradiates the irradiation region 100N with light. In the light emitting unit 4, the light sources 4K to 4N are arranged side by side in order from the upper left side (-x direction and +y direction ends) to the lower right side (+x direction and -y direction ends) in FIGS. 10(a) to 10(b). That is, in the light emitting unit 4, the light source 4K is arranged at the -x direction and +y direction ends, and the light source 4L is arranged at the +x direction and +y direction ends so as to be adjacent to the light source 4K in the +x direction. Further, in the light emitting unit 4, the light source 4M is arranged at the -x direction and -y direction ends so as to be adjacent to the light source 4K in the -y direction, and the light source 4N is arranged at the +x direction and -y direction ends so as to be adjacent to the light source 4M in the +x direction. In this example, when the light source 4K is the first light source, the light source 4L arranged side by side with the light source 4K in the +x direction, which is an example of the first direction, is an example of the second light source. Also, the light source 4M arranged side by side with the light source 4K in the -y direction, which is an example of the second direction, is an example of the third light source.

[0075] In FIG. 10(a), the irradiation regions 100N, 100M, 100L, and 100K are arranged side by side in order from the upper left side (-x direction and +y direction ends) to the lower right side (+x direction and -y direction ends). Further, in FIG. 10(a), the center line 101K of the light irradiated from the light source 4K to the irradiation region 100K, the center line 101L of the light irradiated from the light source 4L to the irradiation region 100L, the center line 101M of the light irradiated from the light source 4M to the irradiation region 100M, and the center line 101N of the light irradiated from the light source 4N to the irradiation region 100N intersect at one intersection 103. Additionally, in FIG. 10(a), the center line 101K, the center line 101L, the center line 101M, and the center line 101N intersect in both the x direction and the y direction. In FIG. 10(a), in the +z direction relative to the intersection 103, the arrangement of the irradiation regions 100K to 100N is inverted in the x and y directions with respect to the arrangement of the light sources 4K to 4N.

[0076] In FIG. 10(b), in order from the upper left side (the ends in the -x and +y directions) to the lower right side (the ends in the +x and -y directions), the irradiation regions 100M, 100N, 100K, and 100L are arranged in sequence. Also, in FIG. 10(b), the center line 101K of the irradiation region 100K irradiated with light from the light sources 4K and 4M arranged in the y direction and the center line 101M of the irradiation region 100M intersect at the intersection 104. Also, the center line 101L of the irradiation region 100L irradiated with light from the light sources 4L and 4N arranged in the y direction and the center line 101N of the irradiation region 100N intersect at the intersection 105. On the other hand, the center line 101K of the irradiation region 100K irradiated with light from the light sources 4K and 4L arranged in the x direction and the center line 101L of the irradiation region 100L do not intersect. Similarly, the center line 101M of the irradiation region 100M irradiated with light from the light sources 4M and 4N arranged in the x direction and the center line 101N of the irradiation region 100N do not intersect.

[0077] And in FIG. 10(b), on the +z direction side of the intersection 104, the arrangement of the irradiation region 100K and the irradiation region 100M is inverted in the y direction with respect to the arrangement of the light sources 4K and 4M. Similarly, on the +z direction side of the intersection 105, the arrangement of the irradiation region 100L and the irradiation region 100N is inverted in the y direction with respect to the arrangement of the light sources 4L and 4N.

[0078] Thus, in the light emitting unit 4, when there are a plurality of light sources of 3 or more, if the center lines of the irradiation regions irradiated with light from at least two light sources selected from the plurality of light sources intersect, a combination of light sources whose center lines of the irradiation regions do not intersect may be included. The light emitting unit 4 can narrow the range in which a non-irradiation region where light is not irradiated by the light sources is formed, by having the center lines of the irradiation regions irradiated with light from at least two light sources selected from a plurality of light sources intersect, as compared with the case where none of the center lines of the irradiation regions irradiated with light from the plurality of light sources intersect.

[0079] When the light emitting unit 4 has three or more light sources, from the viewpoint of further narrowing the range in which the non-irradiation region is formed, it is preferable that the center lines of the irradiation regions irradiated with light from the plurality of light sources intersect at one intersection. For example, in the example shown in FIG. 10(b), between the irradiation region 100K and the irradiation region 100M where the center line 101K and the center line 101M intersect, the range in which a non-irradiation region where light is not irradiated by the light sources 4K and 4M is formed can be narrowed. Also, between the irradiation region 100L and the irradiation region 100N where the center line 101L and the center line 101N intersect, the range in which a non-irradiation region where light is not irradiated by the light sources 4L and 4N is formed can be narrowed. On the other hand, between the irradiation region 100K and the irradiation region 100L where the center line 101K and the center line 101L do not intersect, the range in which a non-irradiation region where light is not irradiated by the light sources 4K and 4L is formed tends to be wide. Similarly, between the irradiation region 100M and the irradiation region 100N where the center line 101M and the center line 101N do not intersect, the range in which a non-irradiation region where light is not irradiated by the light sources 4M and 4N is formed tends to be wide.

[0080] In contrast, as shown in FIG. 10(a), when all the center lines 101K, 101L, 101M, and 101N intersect at one intersection 103, in any of the intervals between the irradiation region 100K and the irradiation region 100M, between the irradiation region 100L and the irradiation region 100N, between the irradiation region 100K and the irradiation region 100L, and between the irradiation region 100M and the irradiation region 100N, the range in which a non-irradiation region where light is not irradiated by the light sources 4K to 4N is formed can be narrowed.

[0081] Figs. 11(a) to (d) are diagrams for explaining the relationship between the light-emitting chip 41 and the lens 42 of the light sources 4K to 4N. Figs. 11(a) to (d) show the relationship between the light-emitting chip 41 and the lens 42 of the light sources 4K to 4N when the light sources 4K to 4N irradiate light as shown in Fig. 10(a). Fig. 11(a) shows the light-emitting chip 41 and the lens 42 of the light source 4K, Fig. 11(b) shows the light-emitting chip 41 and the lens 42 of the light source 4L, Fig. 11(c) shows the light-emitting chip 41 and the lens 42 of the light source 4M, and Fig. 11(d) shows the light-emitting chip 41 and the lens 42 of the light source 4N. Figs. 11(a) to (d) correspond to views of the light-emitting chip 41 and the lens 42 in the light sources 4K to 4N as seen from the -z direction side to the +z direction. Hereinafter, the light-emitting surfaces of the light-emitting chips 41 of the light sources 4K, 4L, 4M, and 4N are denoted as light-emitting surfaces 413, 414, 415, and 416, respectively.

[0082] As shown in Fig. 11(a), in the light source 4K, the light-emitting chip 41 and the lens 42 are arranged such that the light-emitting surface 413 of the light-emitting chip 41 faces the first region 421 of the lens 42. Specifically, in the light source 4K, the light-emitting chip 41 and the lens 42 are arranged such that the center 413C of the light-emitting surface 413 is displaced in the -x direction and the +y direction with respect to the optical axis 420 of the lens 42. Also, in the light source 4K, on the light-emitting surface 413, the long side 413x located on the -y direction side overlaps with the first straight line Lx of the lens 42, and the short side 413y located on the +x direction side overlaps with the second straight line Ly of the lens 42, so that the light-emitting chip 41 and the lens 42 are arranged.

[0083] Also, in the light source 4L, the light-emitting chip 41 and the lens 42 are arranged such that the center 414C of the light-emitting surface 414 is displaced in the +x direction and the +y direction with respect to the optical axis 420 of the lens 42. Also, in the light source 4L, on the light-emitting surface 414, the long side 414x located on the -y direction side overlaps with the first straight line Lx of the lens 42, and the short side 414y located on the -x direction side overlaps with the second straight line Ly of the lens 42, so that the light-emitting chip 41 and the lens 42 are arranged.

[0084] Also, in the light source 4M, the light emitting chip 41 and the lens 42 are arranged such that the center 415C of the light emitting surface 415 is displaced in the -x direction and the -y direction with respect to the optical axis 420 of the lens 42. Also, in the light source 4M, the light emitting chip 41 and the lens 42 are arranged such that the long side 415x located on the +y direction side overlaps with the first straight line Lx of the lens 42, and the short side 415y located on the +x direction side overlaps with the second straight line Ly of the lens 42 on the light emitting surface 415.

[0085] Also, in the light source 4N, the light emitting chip 41 and the lens 42 are arranged such that the center 416C of the light emitting surface 416 is displaced in the +x direction and the -y direction with respect to the optical axis 420 of the lens 42. Also, in the light source 4N, the light emitting chip 41 and the lens 42 are arranged such that the long side 416x located on the +y direction side overlaps with the first straight line Lx of the lens 42, and the short side 416y located on the -x direction side overlaps with the second straight line Ly of the lens 42 on the light emitting surface 416.

[0086] Thus, in the light emitting unit 4 of the present embodiment, the light emitting surfaces 413 of the light emitting chips 41 in the light source 4K, the light emitting surfaces 414 of the light emitting chips 41 in the light source 4L, the light emitting surfaces 415 of the light emitting chips 41 in the light source 4M, and the light emitting surfaces 416 of the light emitting chips 41 in the light source 4N overlap with the first straight line Lx and the second straight line Ly of the lens 42. In other words, there is no gap between the relative positions of the light emitting surfaces 413, 414, 415, 416 with respect to the lens 42. Thereby, it is possible to suppress the formation of a non-irradiation region where light from the light sources 4K to 4L is not irradiated between the irradiation regions 100K, 100L, 100M, 100N on the +z direction side of the intersection 103 where the center lines 101K, 101L, 101M, 101N intersect.

[0087] [Embodiment 4] Subsequently, as Embodiment 4 of the present invention, an aspect in which the light emitting unit 4 has three light sources 4P, 4Q, 4R will be described. Note that the same reference numerals are used for the same configurations as those in the above-described Embodiments 1 to 3, and detailed descriptions thereof are omitted here.

[0088] Figs. 12(a) to 12(b) are diagrams showing the relationship between the light sources 4P to 4R of the light emitting unit 4 of the present embodiment and the irradiation regions 100P to 100R irradiated with the light emitted from the respective light sources 4P to 4R. Although details will be described later, in Figs. 12(a) and 12(b), the relationship between the arrangement of the light sources 4P to 4R and the arrangement of the irradiation regions 100P to 100R is different from each other. Also, Figs. 13 and 14 are diagrams for explaining the relationship between the irradiation region 100P, the irradiation region 100Q, and the irradiation region 100R. Figs. 13 and 14 are views of the light sources 4P to 4R and the irradiation regions 100P to 100R as seen from the +x direction side to the -x direction. Fig. 13 corresponds to the irradiation regions 100P to 100Q shown in Fig. 12(a), and Fig. 14 corresponds to the irradiation regions 100P to 100Q shown in Fig. 12(b).

[0089] The light emitting unit 4 of the present embodiment includes a light source 4P that irradiates the irradiation region 100P with light, a light source 4Q that irradiates the irradiation region 100Q with light, and a light source 4R that irradiates the irradiation region 100R with light. In the light emitting unit 4, the light sources 4P, 4Q, and 4R are arranged in order from the +y direction side to the -y direction. That is, the light source 4P is arranged on the +y direction side with respect to the light source 4Q, and the light source 4Q is arranged on the +y direction side with respect to the light source 4R.

[0090] In Figs. 12(a) and 13, the irradiation regions 100R, 100Q, and 100P are arranged in order from the +y direction side to the -y direction (from the top to the bottom in Fig. 13). Also, as shown in FIG. 12, the center line 101P of the light irradiated from the light source 4P to the irradiation region 100P, the center line 101Q of the light irradiated from the light source 4Q to the irradiation region 100Q, and the center line 101R of the light irradiated from the light source 4R to the irradiation region 100R intersect at one intersection 106. In this example, when the light source 4P is an example of the first light source, the light sources 4Q and 4R are examples of a plurality of second light sources. Also, when the light source 4Q is an example of the first light source, the light sources 4P and 4R are examples of a plurality of second light sources. Also, when the light source 4R is an example of the first light source, the light sources 4P and 4Q are examples of a plurality of second light sources.

[0091] Furthermore, in FIGS. 12(a) and 13, on the +z direction side of the intersection 106, the arrangement of the irradiation region 100P and the irradiation region 100Q is inverted in the y direction with respect to the arrangement of the light source 4P and the light source 4Q. Also, on the +z direction side of the intersection 106, the arrangement of the irradiation region 100P and the irradiation region 100R is inverted in the y direction with respect to the arrangement of the light source 4P and the light source 4R. Also, on the +z direction side of the intersection 106, the arrangement of the irradiation region 100Q and the irradiation region 100R is inverted in the y direction with respect to the arrangement of the light source 4Q and the light source 4R.

[0092] And, as shown in FIG. 12(a), the intersection of the center line 101P, the center line 101Q, and the center line 101R at one intersection 106 results in no non-irradiation region being formed between the irradiation region 100P and the irradiation region 100Q, and between the irradiation region 100Q and the irradiation region 100R on the +z direction side of the intersection 106 where the light from the light sources 4P to 4R is not irradiated. Thereby, compared with the case where the center lines 101P to 101R of the irradiation regions 100P to 100R irradiated with light from the three light sources 4P to 4Q do not intersect at all, the range in which a non-irradiation region where the light sources 4P to 4Q do not irradiate light is formed can be narrowed.

[0093] In FIGS. 12(b) and 14, the irradiation region 100R, the irradiation region 100P, and the irradiation region 100Q are arranged in this order from the +y direction side to the -y direction (from top to bottom in FIG. 14). Also, as shown in Fig. 12(b), the center line 101P of the light irradiated from the light source 4P to the irradiation region 100P and the center line 101R of the light irradiated from the light source 4R to the irradiation region 100R intersect at the intersection 107. Further, the center line 101Q of the light irradiated from the light source 4Q to the irradiation region 100Q and the center line 101R of the light irradiated from the light source 4R to the irradiation region 100R intersect at the intersection 108. Additionally, the center line 101R of the light irradiated from the light source 4R to the irradiation region 100R intersects both the center line 101P of the light irradiated from the light source 4P to the irradiation region 100P and the center line 101Q of the light irradiated from the light source 4Q to the irradiation region 100Q. In this example, the light source 4R is an example of the first light source, and the light sources 4P and 4Q are examples of a plurality of second light sources. On the other hand, as shown in Fig. 12(b), the center line 101P of the light irradiated from the light source 4P to the irradiation region 100P and the center line 101Q of the light irradiated from the light source 4Q to the irradiation region 100Q do not intersect.

[0094] Furthermore, in Figs. 12(b) and 14, on the +z direction side of the intersection 107, the arrangement of the irradiation region 100P and the irradiation region 100R is inverted in the y direction with respect to the arrangement of the light source 4P and the light source 4R. Similarly, on the +z direction side of the intersection 108, the arrangement of the irradiation region 100Q and the irradiation region 100R is inverted in the y direction with respect to the arrangement of the light source 4Q and the light source 4R. Note that in Figs. 12(b) and 14, the arrangement of the irradiation region 100P and the irradiation region 100Q is not inverted with respect to the arrangement of the light source 4P and the light source 4Q.

[0095] And, as shown in Fig. 12(b), since the center line 101P and the center line 101R intersect at the intersection 107, on the +z direction side of the intersection 107, no non-irradiation region where the light from the light sources 4P to 4R is not irradiated is formed between the irradiation region 100P and the irradiation region 100R. Thereby, compared with the case where the center lines 101P to 101R of the irradiation regions 100P to 100R irradiated with light from the three light sources 4P to 4Q do not intersect at all, the range where a non-irradiation region where the light sources 4P to 4Q do not irradiate light is formed can be narrowed.

[0096] Note that, as in the third embodiment, when the light emitting unit 4 has three light sources 4P to 4R, from the viewpoint of making the range in which the non-irradiation region is formed narrower, it is preferable that the center lines 101P to 101R of the irradiation regions 100P to 100R intersect at one intersection 106. For example, in the examples of FIGS. 12(b) and 14, the center line 101P of the irradiation region 100P and the center line 101R of the irradiation region 100R intersect at the intersection 107, so that between the irradiation region 100P and the irradiation region 100R, the range in which the non-irradiation region where light is not irradiated by the light source 4P and the light source 4R is formed can be made narrower. On the other hand, in the examples of FIGS. 12(b) and 14, between the irradiation region 100P and the irradiation region 100Q where the center line 101P and the center line 101Q do not intersect, the range in which the non-irradiation region where light is not irradiated by the light source 4P and the light source 4Q is formed tends to be wider.

[0097] In contrast, in the examples of FIGS. 12(a) and 13, all the center lines 101P, 101Q, and 101R intersect at one intersection 106, so that in both between the irradiation region 100P and the irradiation region 100Q and between the irradiation region 100Q and the irradiation region 100R, the range in which the non-irradiation region where light is not irradiated by the light sources 4P to 4R is formed can be made narrower.

[0098] Here, the light sources 4K to 4N of the third embodiment and the light sources 4P to 4R of the fourth embodiment may be such that, similar to the light sources 4A and 4B of the second embodiment, the light emitting surfaces of the respective light emitting chips 41 are each divided into a plurality of light emitting sections. In this case, similar to the second embodiment, it is preferable that the control unit 8 controls the light emitting operations of the respective light emitting sections so that light is not simultaneously irradiated to the plurality of irradiation sections that form the overlapping region on the irradiation surface irradiated with the light from the light source. Additionally, it is preferable that the control unit 8 does not simultaneously turn on the plurality of light emitting sections that irradiate light to the irradiation sections that form the overlapping region. Thereby, it is suppressed that the amount of light irradiated to the object in the overlapping region becomes excessive.

[0099] In the above-described embodiment, as an example of the housing that houses the plurality of light sources of the light emitting unit 4, the housing 44 of the light emitting unit 4 is illustrated, but the present invention is not limited thereto. The housing that houses the plurality of light sources may be the housing of the optical device 3 that houses the light receiving unit 5, the light emitting driving unit 6, and the light receiving driving unit 7 in addition to the plurality of light sources. Further, as the housing that houses the plurality of light sources, the housing of the distance measuring device 1 that houses the control unit 8 in addition to the plurality of light sources, the light receiving unit 5, the light emitting driving unit 6, and the light receiving driving unit 7 may be used. Further, as the housing that houses the plurality of light sources, the housing does not have to be completely covered by a cover or the like, and may have a gap or an opening as long as it has a structure that suppresses the entry of an object. Then, in the optical device 3 or the distance measuring device 1, as described above, the intersection portion where the center lines of the light irradiated from the plurality of light sources to the irradiation region intersect may be located inside these housings. Thereby, entry of the object around the center line where the amount of light irradiated to the object tends to be excessive is suppressed.

[0100] In the above-described embodiment, in the light emitting unit 4, as an example of the optical system, the lens 42 that refracts the light emitted from the light emitting chip 41 is illustrated. However, as long as it changes the traveling direction of the light emitted from the light emitting chip 41 and expands the irradiation range of the light, the optical system is not limited to the lens 42. As the optical system, for example, a diffractive optical element (DOE) that changes the angle of incident light and emits it may be used.

[0101] In addition, various changes and configuration alternatives that do not depart from the scope of the technical idea of the present invention are included in the present invention.

[0102] (Appended Note) (((1))) A light emitting unit that emits light, An optical system that expands the irradiation range of the light emitted from the light emitting unit as the distance from the light emitting unit increases, A plurality of light sources each having the light emitting unit and the optical system, and irradiating light to different irradiation regions, the plurality of light sources being such that the center lines of the light irradiated from each of the light sources to the irradiation region intersect Light emitting device (((2))) Further comprising a housing for accommodating the plurality of light sources An intersection where the center lines of the light irradiated from the plurality of light sources to the irradiation region intersect is located inside the housing The light emitting device according to ((1)) (((3))) The light emitting unit of each of the light sources includes a plurality of light emitting sections that irradiate light toward respective irradiation sections obtained by dividing the irradiation region into a plurality of parts Further comprising a driving unit that drives the light emitting unit of each of the light sources to individually light the plurality of light emitting sections of the light emitting unit The driving unit does not simultaneously light the light emitting sections that irradiate light to the irradiation sections adjacent to each other in different irradiation regions The light emitting device according to ((1)) or ((2)) (((4))) In the irradiation sections where the light irradiated from each of the light sources to the irradiation region overlaps, the driving unit lights the light emitting section of one light source that irradiates light to a first irradiation section, which is one of the irradiation sections, and does not light the light emitting section of the other light source that irradiates light to a second irradiation section, which is the other irradiation section, and lights the light emitting sections that irradiate light to other irradiation sections other than the first irradiation section and the second irradiation section. The light emitting device according to ((3)) (((5))) The driving unit lights the light emitting sections that irradiate light to the irradiation sections adjacent to each other in different irradiation regions with a time shift. The light emitting device according to ((3)) (((6))) The optical systems and the light emitting units respectively included in the plurality of light sources have the same characteristics as each other When the distance from the plurality of light sources is a predetermined reference distance, the relative positions of the optical system and the light emitting unit are different from each other so that there is no gap between the different irradiation regions. The light emitting device according to any one of ((1)) to ((5)). ((7)) The plurality of light sources include a first light source and a plurality of second light sources arranged side by side in a first direction intersecting the optical axis of the optical system with respect to the first light source. The center line of the light emitted from the first light source intersects any of the center lines of the light emitted from the plurality of second light sources. The light emitting device according to any one of ((1)) to ((6)). ((8)) The light emitting device according to ((7)), wherein the positions of the intersection portions where the center line of the light emitted from the first light source intersects the center lines of the light emitted from the respective second light sources coincide. ((9)) The plurality of light sources include a first light source, a second light source arranged side by side in a first direction intersecting the optical axis of the optical system with respect to the first light source, and a third light source arranged side by side in a second direction intersecting the optical axis and the first direction with respect to the first light source. The center line of the light emitted from the first light source intersects at least one of the center line of the light emitted from the second light source and the center line of the light emitted from the third light source. The light emitting device according to any one of ((1)) to ((6)). ((10)) The light emitting device according to ((9)), wherein the center line of the light emitted from the first light source intersects both the center line of the light emitted from the second light source and the center line of the light emitted from the third light source. ((11)) A light emitting unit that emits light. An optical system that expands the irradiation range of the light emitted from the light emitting unit as it moves away from the light emitting unit. It has a plurality of light sources each having the light emitting unit and the optical system, and irradiating light to different irradiation regions. The arrangement of the plurality of light sources and the arrangement of the plurality of irradiation regions irradiated with light from the plurality of light sources on an irradiation surface having a predetermined distance from the plurality of light sources are inverted. Light emitting device. (((12))) The light emitting device according to any one of ((1)) to ((11)), A light receiving unit that receives light irradiated from the light emitting device and reflected by an object, A distance measuring unit that measures the distance to the object based on the result of light reception by the light receiving unit A distance measuring device comprising. (((13))) The light receiving unit receives light reflected at a position farther from the light emitting device than an intersection where center lines of light irradiated from the plurality of light sources to the irradiation region intersect. The distance measuring device according to ((12)).

[0103] According to the light emitting device according to ((1)), when irradiating light to different irradiation regions with a plurality of light sources, compared with the case where the center lines of the light irradiated from the plurality of light sources to the irradiation region do not intersect, it is possible to suppress the formation of a non-irradiation region where no light is irradiated between the irradiation regions. According to the light emitting device according to ((2)), compared with the case where an intersection where the center lines of the light irradiated from the plurality of light sources to the irradiation region intersect is located outside the housing, it is possible to suppress the irradiation of an excessive amount of light to the object. According to the light emitting device according to ((3)), compared with the case of simultaneously lighting light emitting sections that irradiate light to adjacent irradiation sections in different irradiation regions, it is possible to suppress the non-uniformity of the amount of light irradiated to the irradiation region. According to the light-emitting device according to ((4)), when the light-emitting section of one light source that irradiates the first irradiation section is lit and the light-emitting section of the other light source that irradiates the second irradiation section is not lit, compared with the case where the light-emitting section that irradiates other irradiation sections other than the first irradiation section and the second irradiation section is not lit, the time required until all irradiation sections are irradiated with light can be reduced. According to the light-emitting device according to ((5)), compared with the case where the light-emitting sections that irradiate the adjacent irradiation sections in different irradiation regions are not lit with a temporal shift, it is possible to suppress the occurrence of an irradiation section where no light is irradiated. According to the light-emitting device according to ((6)), compared with the case where the relative position between the optical system and the light-emitting section is not determined so that there is no gap between different irradiation regions, it is less likely that a non-irradiation region is formed between adjacent irradiation regions. According to the light-emitting device according to ((7)), compared with the case where the center line of the light emitted from the first light source intersects only one of the center lines of the light emitted from the plurality of second light sources, the range in which the non-irradiation region is formed can be narrowed. According to the light-emitting device according to ((8)), compared with the case where the positions of the intersection portions where the center line of the light emitted from the first light source intersects the center lines of the light emitted from the respective second light sources do not match, the range in which the non-irradiation region is formed can be made narrower. According to the light-emitting device according to ((9)), compared with the case where the center line of the light emitted from the first light source does not intersect the center line of the light emitted from the second light source or the third light source, the range in which the non-irradiation region is formed can be narrowed. According to the light-emitting device according to ((10)), compared with the case where the center line of the light emitted from the first light source intersects only the center line of the light emitted from one of the second light source and the third light source, the range in which the non-irradiation region is formed can be narrowed. According to the light-emitting device according to ((11)), when irradiating different irradiation regions with light using a plurality of light sources, compared with the case where the center lines of the light irradiated from the plurality of light sources to the irradiation regions do not intersect, it is possible to suppress the formation of a non-irradiation region where no light is irradiated between the irradiation regions. According to the distance measuring device according to ((12)), when irradiating light to different irradiation regions by a plurality of light sources, it is possible to suppress the formation of a non-irradiation region where light is not irradiated between the irradiation regions as compared with the case where the center lines of the light irradiated from the plurality of light sources do not intersect. According to the distance measuring device according to ((13)), it is possible to suppress excessive light from entering the light receiving unit as compared with the case where the light receiving unit receives the light reflected at the intersection where the center lines of the light intersect.

Explanation of reference numerals

[0104] 1... Distance measuring device, 3... Optical device, 4... Light emitting unit, 4A, 4B... Light sources, 5... Light receiving unit, 6... Light emitting drive unit, 7... Light receiving drive unit, 8... Control unit, 41... Light emitting chip, 42... Lens, 100A, 100B... Irradiation regions, 101A, 101B... Center lines

Claims

1. A light emitting unit that emits light, an optical system that expands the irradiation range of the light emitted from the light emitting unit as it moves away from the light emitting unit, a plurality of light sources each having the light emitting unit and the optical system, and irradiating light to different irradiation regions, and a plurality of light sources where the center lines of the light irradiated from each of the light sources to the irradiation region intersect, A light emitting device.

2. Further comprising a housing that houses the plurality of light sources, The intersection where the center lines of the light irradiated from the plurality of light sources to the irradiation region intersect is located inside the housing The light emitting device according to claim 1.

3. The light emitting unit of each of the light sources includes a plurality of light emitting sections that irradiate light toward each of the irradiation sections obtained by dividing the irradiation region into a plurality, Further comprising a driving unit that drives the light emitting unit of each of the light sources to individually light the plurality of light emitting sections of the light emitting unit, The driving unit does not simultaneously light the light emitting sections that irradiate light to the adjacent irradiation sections in different irradiation regions The light emitting device according to claim 1.

4. In the irradiation section where the light irradiated from each of the light sources to the irradiation region overlaps, the driving unit lights the light emitting section of one light source that irradiates light to a first irradiation section that is one of the irradiation sections, and does not light the light emitting section of the other light source that irradiates light to a second irradiation section that is the other irradiation section, and lights the light emitting sections that irradiate light to other irradiation sections other than the first irradiation section and the second irradiation section. The light emitting device according to claim 3.

5. The optical system and the light emitting unit that each of the plurality of light sources has have equal characteristics to each other, The plurality of light sources have different relative positions of the optical system and the light emitting unit so that there is no gap between different irradiation regions when the distance from the plurality of light sources is a predetermined reference distance The light emitting device according to claim 1.

6. The plurality of light sources include a first light source and a plurality of second light sources arranged side by side in a first direction intersecting the optical axis of the optical system with respect to the first light source, The center line of the light irradiated from the first light source intersects any of the center lines of the light emitted from the plurality of second light sources The light emitting device according to claim 1.

7. The light emitting device according to claim 6, wherein the positions of the intersections where the center line of the light emitted from the first light source intersects the center lines of the light emitted from the respective second light sources coincide.

8. The plurality of light sources include a first light source, a second light source arranged side by side in a first direction intersecting the optical axis of the optical system with respect to the first light source, and a third light source arranged side by side in a second direction intersecting the optical axis and the first direction with respect to the first light source. The center line of the light emitted from the first light source intersects at least one of the center line of the light emitted from the second light source and the center line of the light emitted from the third light source. The light-emitting device according to claim 1.

9. The light-emitting device according to claim 8, wherein the center line of the light emitted from the first light source intersects both the center line of the light emitted from the second light source and the center line of the light emitted from the third light source.

10. A light-emitting unit that emits light; An optical system that expands the irradiation range of the light emitted from the light-emitting unit as it moves away from the light-emitting unit; A plurality of light sources each having the light-emitting unit and the optical system, and irradiating light to different irradiation regions; The arrangement of the plurality of light sources and the arrangement of the plurality of irradiation regions irradiated with light from the plurality of light sources at a predetermined distance from the plurality of light sources on the irradiation surface are inverted. Light-emitting device.

11. The light-emitting device according to any one of claims 1 to 10; A light-receiving unit that receives light irradiated from the light-emitting device and reflected by an object; A distance measuring unit that measures the distance to the object based on the result of light reception by the light-receiving unit A distance measuring device comprising.

12. The distance measuring device according to claim 11, wherein the light-receiving unit receives light reflected at a position farther from the light-emitting device than the intersection portion where the center lines of the light irradiated from the plurality of light sources to the irradiation region intersect.

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