Light-emitting device and distance measurement device

Abstract

Provided are a light-emitting device and a distance measurement device that can optimize the structure of wirings for light-emitting elements.　A light-emitting device (1) according to the present disclosure comprises: a plurality of light-emitting units (26-28) disposed in one direction (U); a plurality of light-emitting elements (23), at least one of which is provided to each of the plurality of light-emitting units (26-28) and each of which has a first terminal (anode electrode 47) and a second terminal (cathode electrode 48); a plurality of first terminal wirings (31-33) that include M (M is an integer of 2 or greater) first wirings (31a-33a) and N (N is an integer of 2 of greater) second wirings (31b-33b) which respectively cross the M first wirings and each of which is electrically connected to at least one of the M first wirings, the plurality of first terminal wirings (31-33) being electrically connected to the first terminals (the anode electrodes 47) of the plurality of light-emitting elements (23); and a plurality of second terminal wirings (41) that are electrically connected to the second terminals (the cathode electrodes 48) of the plurality of light-emitting elements (23) and are respectively electrically connected to P (P is an integer of 2 or greater) light-emitting elements among the light-emitting elements (23). The light-emitting device (1) of the present disclosure can be applied to a distance measurement device.

Description

Light emitting device and distance measuring device

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

[0002] An optical module that scans a linear light beam in a direction substantially perpendicular to the linear direction has been proposed (see Patent Document 1). Patent Document 1 describes that the linear light beam is emitted by, for example, a semiconductor laser in which a plurality of light-emitting elements are arranged in a one-dimensional direction, and cites a VCSEL (Vertical Cavity Surface Emitting Laser) as an example of the semiconductor laser.

[0003] International Publication No. 2020 / 105239

[0004] However, as the number of light-emitting elements in a VCSEL increases, the wiring connected to each light-emitting element becomes longer, and the wiring length also varies. This causes fluctuations in wiring capacitance and impedance between the wiring, which can lead to variations in the light emission timing and light intensity of each light-emitting element. If a distance is measured by irradiating an object with light emitted by a light-emitting device with such variations, the accuracy of the distance measurement will decrease.

[0005] Therefore, the present disclosure provides a light emitting device and a distance measuring device that can optimize the structure of wiring for light emitting elements.

[0006] In order to solve the above-mentioned problems, according to the present disclosure, there is provided a light emitting device comprising: a plurality of light emitting sections arranged in one direction; a plurality of light emitting elements, at least one of which is provided in each of the plurality of light emitting sections, each having a first and a second terminal; M first wirings (M is an integer of 2 or more) and N second wirings (N is an integer of 2 or more), each of which intersects with the M first wirings and is electrically connected to at least one of the M first wirings, a plurality of first terminal wirings electrically connected to the first terminals of the plurality of light emitting elements; a plurality of second terminal wirings electrically connected to the second terminals of the plurality of light emitting elements, each of which is electrically connected to P (P is an integer of 2 or more) of the light emitting elements; a plurality of selection circuits respectively connected to one of the plurality of first terminal wirings and the plurality of second terminal wirings and selecting a corresponding one of the light emitting elements; and a plurality of drive circuits respectively connected to the other of the plurality of first terminal wirings and the plurality of second terminal wirings and driving a corresponding one of the light emitting elements.

[0007] The N may be an integer that is the same as or different from the M, and the P may be an integer that is the same as or different from at least one of the M and the N.

[0008] The display device may further include a plurality of capacitors electrically connected to the one of the first and second terminal wirings, for storing electric charges for causing current to flow to the plurality of light-emitting elements.

[0009] The plurality of light emitting sections may be arranged in one or more rows along the one direction.

[0010] The plurality of light emitting portions may be arranged in a staggered pattern along the one direction.

[0011] The plurality of light emitting portions may be arranged along a direction inclined with respect to the one direction.

[0012] The longitudinal directions of the plurality of light emitting sections may be arranged in a direction inclined with respect to the one direction.

[0013] Each of the plurality of light emitting sections may have two or more of the light emitting elements arranged in one or more rows along the longitudinal direction.

[0014] Each of the plurality of light emitting sections may have two or more of the light emitting elements arranged in a staggered pattern along the longitudinal direction.

[0015] Each of the plurality of light emitting sections may have two or more of the light emitting elements arranged in one or more rows along a direction inclined with respect to the longitudinal direction.

[0016] The N second wirings may extend in the one direction.

[0017] The plurality of light emitting sections may be arranged at regular intervals along a direction in which the N second wirings extend.

[0018] The N second wirings may be arranged so as to be alternately bent in a first direction inclined with respect to the one direction and in a second direction intersecting the first direction, and each of the plurality of light-emitting units may be arranged in accordance with the period at which the N second wirings are bent.

[0019] Each of the M first wirings may be arranged so as to intersect with one or more of the light emitting portions arranged along the one direction.

[0020] Each of the plurality of second terminal wirings may be arranged so as to intersect with one or more of the light emitting portions arranged along the one direction.

[0021] Each of the plurality of second terminal wirings may be provided corresponding to one of the plurality of light-emitting sections, and may be connected to the second terminal of the light-emitting element in the corresponding light-emitting section.

[0022] The light emitting device may further include a control unit that controls the light emission of each of the plurality of light emitting units individually.

[0023] When each of the plurality of light-emitting sections includes a plurality of the light-emitting elements, the control section may synchronize the plurality of light-emitting elements to light up or turn off.

[0024] Further, according to the present disclosure, in a distance measuring device including a light emitting device that emits light toward an object, and a distance measuring unit that receives light reflected by the object and measures the distance to the object, the light emitting device comprises: a plurality of light emitting units arranged in one direction; a plurality of light emitting elements, at least one of which is provided in each of the plurality of light emitting units, each having a first and a second terminal; M first wirings (M is an integer of 2 or more) and N second wirings (N is an integer of 2 or more), each of which intersects with the M first wirings and is electrically connected to at least one of the M first wirings, a plurality of first terminal wirings electrically connected to the first terminals of the plurality of light emitting elements; a plurality of second terminal wirings electrically connected to the second terminals of the plurality of light emitting elements, each of which is electrically connected to P (P is an integer of 2 or more) of the light emitting elements; and a plurality of selection circuits respectively connected to one of the plurality of first terminal wirings and the plurality of second terminal wirings, and each selecting a corresponding light emitting element. There is provided a distance measuring device comprising: a plurality of drive circuits connected to the other of the plurality of first terminal wirings and the plurality of second terminal wirings, respectively, and driving the corresponding light emitting elements; and an optical scanning unit that scans the one-directional light emitted by the plurality of light emitting units in a direction intersecting the one direction.

[0025] 1A is a layout diagram showing a first example of a light-emitting device according to a first embodiment of the present disclosure. FIG. 1B is a layout diagram showing a second example of a light-emitting device according to the first embodiment of the present disclosure. FIG. 1C is a plan view showing a row of light-emitting units in a light-emitting device according to the first embodiment of the present disclosure. FIG. 1D is a circuit diagram of a light-emitting device according to the first embodiment of the present disclosure. FIG. 1E is a circuit diagram of a plurality of light-emitting units of FIG. 1A. FIG. 1F is a diagram showing a charging operation of a capacitor according to the first embodiment of the present disclosure. FIG. 1G is a diagram showing a light-emitting operation of a light-emitting element according to the first embodiment of the present disclosure. FIG. 1H is a circuit diagram showing a modified example of a light-emitting device according to the first embodiment of the present disclosure. FIG. 1I is a graph illustrating performance of a light-emitting device according to the first embodiment of the present disclosure. FIG. 1J is a cross-sectional view showing an example of the cross-sectional structure of a light-emitting device having a VCSEL structure. FIG. 1J is a circuit diagram showing the structure of a light-emitting device according to a first comparative example. FIG. 1L is a layout diagram showing the configuration of a light-emitting device according to a second embodiment of the present disclosure. FIG. 1L is a layout diagram of a first example of a light-emitting device according to the second embodiment of the present disclosure. FIG. 1J is a layout diagram of a second example of a light-emitting device according to the second embodiment of the present disclosure. FIG. 1L is a diagram showing the wiring structure of a light-emitting device according to a second comparative example. FIG. 1J is a diagram showing the wiring structure of a light-emitting device according to the second embodiment of the present disclosure. FIG. 1L is a layout diagram showing the configuration of a light-emitting device according to a third embodiment of the present disclosure. FIG. 1I is a plan view of a light-emitting unit according to a first example of a light-emitting device according to a third embodiment of the present disclosure. 19 is a plan view of a light-emitting section according to a second example of a light-emitting device according to a third embodiment of the present disclosure. FIG. 20 is a plan view of a light-emitting section according to a third example of a light-emitting device according to the third embodiment of the present disclosure. FIG. 21 is a diagram showing a first modified example of a light-emitting device according to the third embodiment of the present disclosure. FIG. 22 is a diagram showing a second modified example of a light-emitting device according to the third embodiment of the present disclosure. FIG. 23 is a circuit diagram showing a light-emitting device according to a fourth embodiment of the present disclosure. FIG. 24 is a circuit diagram showing a first example of a light-emitting device according to a fifth embodiment of the present disclosure. FIG. 25 is a circuit diagram showing a second example of a light-emitting device according to the fifth embodiment of the present disclosure. FIG. 26 is a circuit diagram showing a third example of a light-emitting device according to the fifth embodiment of the present disclosure. FIG. 27 is a circuit diagram showing a fourth example of a light-emitting device according to the fifth embodiment of the present disclosure. FIG. 28 is another circuit diagram showing the structure of the fourth example of a light-emitting device according to the fifth embodiment of the present disclosure. FIG. 29 is a circuit diagram showing various examples of the structure of the fifth example of a light-emitting device according to the fifth embodiment of the present disclosure. FIG. 29 is a circuit diagram showing the structure of a sixth example of a light-emitting device according to the fifth embodiment of the present disclosure. FIG. 29 is a timing chart showing the operation of the light-emitting device of FIG.24 is a diagram illustrating a configuration of a light emitting device according to a sixth embodiment of the present disclosure. FIG. 25 is a diagram illustrating a configuration of channels of the light emitting device. FIG. 26 is a diagram illustrating irradiation light of each channel. FIG. 27 is a plan view illustrating a distance measuring device to which the light emitting device according to the sixth embodiment of the present disclosure is applied. FIG. 28 is a graph illustrating a first example of the emission timing of the irradiation light of each channel. FIG. 29 is a diagram schematically illustrating an example of the irradiation direction of the irradiation light of each channel of FIG. 23. FIG. 29 is a graph illustrating a second example of the emission timing of the irradiation light of each channel. FIG. 29 is a graph illustrating a third example of the emission timing of the irradiation light of each channel. FIG. 29 is a diagram schematically illustrating an example of the irradiation direction of the irradiation light of each channel of FIG. 26. FIG. 29 is a graph illustrating a fourth example of the emission timing of the irradiation light of each channel. FIG. 30 is a graph illustrating a fifth example of the emission timing of the irradiation light of each channel. FIG. 31 is a graph illustrating a sixth example of the emission timing of the irradiation light of each channel. FIG. 32 is a graph illustrating a seventh example of the emission timing of the irradiation light of each channel. FIG. 33 is a cross-sectional view of a ToF sensor according to a seventh embodiment of the present disclosure. FIG. 34 is a block diagram illustrating a configuration of a distance measuring device according to the seventh embodiment of the present disclosure. FIG. 35 is an explanatory diagram of an STL system. FIG. 36 is an explanatory diagram of the distance measurement principle of the STL system. FIG. 37 is a block diagram illustrating an example of a schematic configuration of a vehicle control system. FIG. 2 is an explanatory diagram showing an example of the installation positions of an outside-vehicle information detection unit and an imaging unit.

[0026] Hereinafter, embodiments of a light emitting device and a distance measuring device will be described with reference to the drawings. The following description will focus on the main components of the light emitting device and the distance measuring device, but the light emitting device and the distance measuring device may include components and functions that are not shown or described. The following description does not exclude components and functions that are not shown or described.

[0027] First Embodiment FIG. 1A is a layout diagram illustrating a first example of a light-emitting device 1 according to a first embodiment of the present disclosure. As shown in FIG. 1A, the light-emitting device 1 according to the first embodiment has a plurality of light-emitting units 26, 27, and 28 arranged in one direction U. Each of the plurality of light-emitting units 26 to 28 has one or more light-emitting elements (VCSEL Emitters) 23. Specifically, the light-emitting device 1 in FIG. 1A has light-emitting elements 23A1, 23B1, and 23C1 arranged in light-emitting unit 26, light-emitting elements 23A2, 23B2, and 23C2 arranged in light-emitting unit 27, and light-emitting elements 23A3, 23B3, and 23C3 arranged in light-emitting unit 28. Like the light-emitting units 26 to 28, the light-emitting elements 23A1 to 23C3 are arranged in one direction U.

[0028] 1A shows a light-emitting device 1 having three light-emitting sections 26 to 28. The light-emitting device 1 has three light-emitting elements 23 for each of the light-emitting sections 26 to 28. The number of light-emitting sections and the number of light-emitting elements 23 in each light-emitting section are arbitrary. In this specification, a plurality of light-emitting elements 23 arranged in one direction as shown in FIG. 1A is referred to as a light-emitting element array.

[0029] The light-emitting units 26 to 28 are each configured, for example, by a different semiconductor chip. The light-emitting units 26 to 28 may be arranged on a single semiconductor chip such as a VCSEL. Alternatively, each of the light-emitting units 26 to 28 does not necessarily have to be a semiconductor chip, and may be a discrete component in which multiple light-emitting elements 23 are mounted on a support substrate.

[0030] The following description will mainly focus on VCSELs having light-emitting portions 26 to 28. FIG. 1A shows an example in which the planar shape of each light-emitting portion is rectangular, and the planar shape of each light-emitting element 23 included in each light-emitting portion is also rectangular. Each light-emitting element 23 has, for example, an anode electrode 47 and a cathode electrode 48. In the example shown in FIG. 1A, the longitudinal direction of the light-emitting element 23 is inclined relative to the longitudinal direction of the light-emitting portion, but both longitudinal directions may be approximately parallel. Furthermore, the planar shapes of each light-emitting portion and each light-emitting element 23 are not necessarily limited to a rectangular shape and may be, for example, a circular shape.

[0031] The light-emitting device 1 has M (M is an integer of 2 or greater) anode horizontal wires and N (N is an integer of 2 or greater) anode vertical wires. The light-emitting device 1 in Fig. 1A shows an example having three anode horizontal wires 31a, 32a, and 33a and three anode vertical wires 31b, 32b, and 33b. That is, in the example of Fig. 1A, M=3 and N=3.

[0032] The anode vertical wiring 31b is arranged so as to intersect with the anode horizontal wirings 31a, 32a, and 33a. Similarly, the anode vertical wirings 32b and 33b are arranged so as to intersect with the anode horizontal wirings 31a, 32a, and 33a, respectively.

[0033] The light-emitting device 1 also has a plurality of cathode wirings 41 corresponding to the plurality of light-emitting sections 26 to 28. Specifically, the cathode wiring 41a is connected to the cathode electrode 48 of each light-emitting element 23 in the light-emitting section 26, the cathode wiring 41b is connected to the cathode electrode 48 of each light-emitting element 23 in the light-emitting section 27, and the cathode wiring 41c is connected to the cathode electrode 48 of each light-emitting element 23 in the light-emitting section 28.

[0034] The cathode wirings 41a, 41b, and 41c are arranged so as to intersect with the light-emitting sections 26 to 28 arranged in one direction U. Similarly, the anode horizontal wirings 31a, 32a, and 33a are arranged so as to intersect with the light-emitting sections 26 to 28.

[0035] In this specification, the anode horizontal wires 31a, 32a, and 33a arranged to intersect with the light-emitting portions 26 to 28 are also referred to as first wires, and the anode vertical wires 31b, 32b, and 33b are also referred to as second wires.

[0036] The anode vertical wirings 31b, 32b, 33b are arranged so as to be bent alternately in a first direction X inclined with respect to the direction U and in a second direction Y intersecting the first direction X (for example, perpendicular to the first direction X).

[0037] 1A, the light-emitting portions 26 to 28 are arranged at regular intervals along the direction in which the anode vertical wirings 31b, 32b, and 33b extend. More specifically, the light-emitting portions 26 to 28 are arranged in accordance with the period in which the anode vertical wirings 31b, 32b, and 33b bend.

[0038] The anode horizontal wire 31a is electrically connected to the anode vertical wire 31b, the anode horizontal wire 32a is electrically connected to the anode vertical wire 32b, and the anode horizontal wire 33a is electrically connected to the anode vertical wire 33b. The anode horizontal wires 31a-33a and the anode vertical wires 31b-33b are arranged, for example, on different wiring layers, and the anode horizontal wires 31a-33a and the anode vertical wires 31b-33b are electrically connected by contacts that penetrate between the two wiring layers. In this specification, these contacts are referred to as anode contacts. In this specification, the anode horizontal wire 31a and the anode vertical wire 31b are referred to as first anode wires 31, the anode horizontal wire 32a and the anode vertical wire 32b are referred to as second anode wires 32, and the anode horizontal wire 33a and the anode vertical wire 33b are referred to as third anode wires 33.

[0039] The first to third anode wirings 31 to 33 are electrically insulated from each other. In this specification, first to Rth anode wirings are provided. R is an integer of 2 or more. In the example of FIG. 1A, M = N = R = 3. However, in cases where two or more of the multiple light-emitting elements 23 in each light-emitting section are caused to emit light simultaneously, M, N, and R may each be a different integer.

[0040] In Fig. 1A, in order to distinguish the first to third anode wirings 31 to 33 from one another, the first anode wiring 31 is shown with a thick solid line, the second anode wiring 32 is shown with a thick dashed line, and the third anode wiring 33 is shown with a thin solid line. Similar notations are used in the circuit diagrams (Figs. 2A and 2B) described below. In Fig. 1A, in order to distinguish the first to third anode wirings 31 to 33 from the cathode wiring 41, the first to third anode wirings 31 to 33 are shown in gray, and the cathode wiring 41 is shown with a solid line.

[0041] The anode vertical wiring 31b is connected to the anode electrodes 47 of the light emitting elements 23A1, 23B1, and 23C1. The anode vertical wiring 32b is connected to the anode electrodes 47 of the light emitting elements 23A2, 23B2, and 23C2. The anode vertical wiring 33b is connected to the anode electrodes 47 of the light emitting elements 23A3, 23B3, and 23C3.

[0042] The cathode wiring 41a is connected to the cathode electrodes 48 of the light emitting elements 23A1, 23A2, and 23A3. The cathode wiring 41b is connected to the cathode electrodes 48 of the light emitting elements 23B1, 23B2, and 23B3. The cathode wiring 41c is connected to the cathode electrodes 48 of the light emitting elements 23C1, 23C2, and 23C3.

[0043] As described above, the light emitting elements 23 in the light emitting sections 26 to 28 in FIG. 1A are connected to different types of anode wiring or cathode wiring.

[0044] FIG. 1B is a layout diagram showing a second example of the light-emitting device 1 according to the first embodiment of the present disclosure. In FIG. 1B, the connection between the horizontal anode wirings 31a to 33a and the vertical anode wirings 31b to 33b and the light-emitting sections 26 to 28 in FIG. 1A is reversed. FIG. 1B differs from FIG. 1A in that the vertical anode wirings 31b, 32b, and 33b are arranged to intersect with the light-emitting sections 26 to 28. The horizontal anode wirings 31a, 32a, and 33a are arranged in a direction inclined with respect to the direction U. In this specification, the vertical anode wirings 31b, 32b, and 33b in FIG. 1B are referred to as first wirings, and the horizontal anode wirings 31a, 32a, and 33a are referred to as second wirings.

[0045] 1B are arranged so as to bend alternately in a first direction X that is inclined with respect to one direction U and in a second direction Y that intersects with the first direction X. Furthermore, the plurality of light-emitting units 26 to 28 are arranged along the extending direction of the anode vertical wires 31b, 32b, 33b, respectively, in accordance with the period at which the anode vertical wires 31b, 32b, 33b are bent.

[0046] 1A are arranged in the same manner as the anode horizontal wirings 31a to 33a, and are therefore referred to as cathode horizontal wirings in this specification. The cathode wirings 41a to 41c in FIG. 1B are arranged in the same manner as the anode vertical wirings 31b to 33b, and are therefore referred to as cathode vertical wirings in this specification.

[0047] In this specification, a plurality of light-emitting units (light-emitting units 26 to 28 in FIG. 1A ) arranged along one direction U are referred to as a light-emitting unit row 29. FIG. 1C is a plan view showing the light-emitting unit row 29 of the light-emitting device 1 according to the first embodiment of the present disclosure. The light-emitting device 1 according to the present disclosure is characterized by including the light-emitting unit row 29 extending in one direction, but the light-emitting unit row 29 may be composed of multiple rows. The number of light-emitting unit rows 29 is not important. FIG. 1C shows an example in which the light-emitting device 1 according to the present disclosure includes two light-emitting unit rows 29a and 29b. Each of the light-emitting unit rows 29a and 29b has three light-emitting units 26 to 28 arranged along one direction U. Note that the following describes an example in which the light-emitting device 1 includes a single light-emitting unit row 29.

[0048] 1A to 1C show an example in which a plurality of light-emitting units are arranged in one direction U, and each light-emitting unit has three light-emitting elements 23 arranged along the one direction U. This makes it possible to emit linear light extending in the one direction U.

[0049] [Circuit Structure of Light-Emitting Device 1] Fig. 2A is a circuit diagram of the light-emitting device 1 according to the first embodiment of the present disclosure. In Fig. 2A, a plurality of light-emitting elements 23 are arranged in a two-dimensional array, but in reality, the plurality of light-emitting elements 23 are arranged in one direction as shown in Fig. 1A or 1B. In Fig. 2A, the anode horizontal wirings 31a, 32a, and 33a extend in the horizontal direction and are arranged in the vertical direction. The anode vertical wirings 31b, 32b, and 33b extend in the vertical direction and are arranged in the horizontal direction.

[0050] The light emitting device 1 has a plurality of transistors 24 electrically connected to a plurality of light emitting elements 23. These transistors 24 are, for example, N-type MOS (Metal-Oxide-Semiconductor) transistors. Fig. 2A shows an example in which the light emitting device 1 according to the first embodiment includes 9x9 light emitting elements 23 and 9x9 transistors 24.

[0051] As shown in FIG. 2A, the light-emitting device 1 according to the first embodiment further includes a plurality of first capacitors 34, a plurality of second capacitors 35, a plurality of third capacitors 36, a first selection circuit 37, a second selection circuit 38, a third selection circuit 39, and a plurality of gate wirings 42.

[0052] The first to third capacitors 34 to 36 are examples of the first to Rth capacitors of the present disclosure, and the first to third selection circuits 37 to 39 are examples of the first to Rth selection circuits of the present disclosure. Figure 2A shows an example where R=3, similar to Figure 1A.

[0053] The light emitting device 1 according to the first embodiment has K (K is an integer of 2 or more) sets of anode horizontal wirings 31a to 33a, each set consisting of the anode horizontal wirings 31a to 33a. The light emitting device 1 according to the first embodiment also has L (L is an integer of 2 or more) sets of anode vertical wirings 31b to 33b, each set consisting of the anode vertical wirings 31b to 33b. When K≧3 and L≧3, the number of light emitting elements 23 shown in FIG. 2A is M(K−2)×N(L−2), where M, N, K, and L are used.

[0054] The first selection circuit 37 includes transistors 37a and 37b connected in series. Similarly, the second selection circuit 38 includes transistors 38a and 38b connected in series. Similarly, the third selection circuit 39 includes transistors 39a and 39b connected in series. The transistors 37a, 38a, and 39a are, for example, P-type MOS transistors. The transistors 37b, 38b, and 39b are, for example, N-type MOS transistors. The transistors 37a, 38a, and 39a are examples of first switches of the present disclosure. The transistors 37b, 38b, and 39b are examples of second switches of the present disclosure.

[0055] [First to Third Anode Wirings 31-33] The first anode wiring 31 has a mesh-like circuit structure composed of a plurality of anode horizontal wirings 31a and a plurality of anode vertical wirings 31b. These anode horizontal wirings 31a and anode vertical wirings 31b are electrically connected to each other at the intersections of the anode horizontal wirings 31a and the anode vertical wirings 31b. Similarly, the second anode wiring 32 includes a plurality of anode horizontal wirings 32a and a plurality of anode vertical wirings 32b that are electrically connected to each other, and the third anode wiring 33 includes a plurality of anode horizontal wirings 33a and a plurality of anode vertical wirings 33b that are electrically connected to each other. As described above, the anode vertical wirings 31b-33b are each electrically connected to at least one of the anode horizontal wirings 31a-33a.

[0056] The first to third anode wirings 31 to 33 are examples of first terminal wirings of the present disclosure. In this specification, the anode horizontal wiring (first wiring) 31a may be referred to as the first horizontal wiring 31a, and the anode vertical wiring (second wiring) 31b may be referred to as the first vertical wiring 31b. Similarly, in this specification, the anode horizontal wirings 32a and 33a may be referred to as the second horizontal wiring 32a and the third horizontal wiring 33a, respectively, and the anode vertical wirings 32b and 33b may be referred to as the second vertical wiring 32b and the third vertical wiring 33b, respectively.

[0057] The first to third horizontal wirings 31a to 33a extend in the horizontal direction and are arranged adjacent to each other in the vertical direction. The first to third horizontal wirings 31a to 33a may include bent portions or curved portions as shown in FIGS. 1A and 1B.

[0058] The first to third vertical wirings 31b to 33b extend vertically and are arranged adjacent to each other in the horizontal direction. The first to third vertical wirings 31b to 33b may include bent portions or curved portions as shown in Figures 1A and 1B.

[0059] FIG. 2A shows five sets (i.e., K=5) of first to third horizontal wirings (first wirings) 31a to 33a. In FIG. 2A, the first, second, third, fourth, and fifth sets of first to third horizontal wirings 31a to 33a are arranged in order from top to bottom. In each set, the first horizontal wiring 31a, the second horizontal wiring 32a, and the third horizontal wiring 33a are arranged in order from top to bottom. The first set of first to third horizontal wirings 31a to 33a and the fifth set of first to third horizontal wirings 31a to 33a are arranged so as to sandwich 9×9 light-emitting elements 23 therebetween. Each of the second to fourth sets of first to third horizontal wirings 31a to 33a is arranged along one row (nine light-emitting elements) 23.

[0060] FIG. 2A further shows five sets (i.e., L=5) of first to third vertical wirings (second wirings) 31b to 33b. In FIG. 2A, the first, second, third, fourth, and fifth sets of first to third vertical wirings 31b to 33b are arranged in order from left to right. In each set, the first vertical wiring 31b, the second vertical wiring 32b, and the third vertical wiring 33b are arranged in order from left to right. The first set of first to third vertical wirings 31b to 33b and the fifth set of first to third vertical wirings 31b to 33b are arranged so as to sandwich 9×9 light-emitting elements 23 therebetween. Each of the second to fourth sets of first to third vertical wirings 31b to 33b is arranged along one column (nine light-emitting elements) 23.

[0061] The anode of each light-emitting element 23 is electrically connected to one of the first to third vertical wirings 31b to 33b. For example, the light-emitting element 23 in the leftmost column is electrically connected to the first vertical wiring 31b in the second set of first to third vertical wirings 31b to 33b. The light-emitting element 23 in the rightmost column is electrically connected to the third vertical wiring 33b in the fourth set of first to third vertical wirings 31b to 33b. The anode of each light-emitting element 23 may be electrically connected to one of the first to third horizontal wirings 31a to 33a instead of being electrically connected to one of the first to third vertical wirings 31b to 33b. The anode is an example of a first terminal in the present disclosure.

[0062] [Cathode Wiring 41] Each cathode wiring 41 extends in the horizontal direction and is electrically connected to the cathodes of three light-emitting elements 23. Specifically, each cathode wiring 41 is electrically connected to one light-emitting element 23 electrically connected to the first vertical wiring 31b, one light-emitting element 23 electrically connected to the second vertical wiring 32b, and one light-emitting element 23 electrically connected to the third vertical wiring 33b. These three light-emitting elements 23 are adjacent to each other in one direction U. FIG. 2A shows 27 cathode wirings 41 for 81 light-emitting elements 23. The number of light-emitting elements 23 connected to each cathode wiring 41 is not limited to three. Each cathode wiring 41 may be electrically connected to the cathodes of P light-emitting elements 23 (P is an integer greater than or equal to 2). The cathode wiring 41 is an example of a second terminal wiring of the present disclosure. The cathode is an example of a second terminal of the present disclosure.

[0063] 2A is connected to the same number of light-emitting elements 23 as the number of the first to N-th vertical wirings, as described above. That is, P=N. On the other hand, when each cathode wiring 41 extends in the vertical direction, it is connected to the same number of light-emitting elements 23 as the number of the first to M-th horizontal wirings (that is, P=M). In this way, P is the same number as at least one of N and M.

[0064] In the above description, an example has been described in which a plurality of light-emitting elements 23 are connected to first to M-th horizontal wires, first to N-th vertical wires, and a plurality of second terminal wires electrically connected in P units, but the light-emitting device according to the present disclosure does not need to include all of the first to M-th horizontal wires, first to N-th vertical wires, and a plurality of second terminal wires electrically connected in P units. For example, a configuration in which a plurality of light-emitting devices are connected to first to M-th horizontal wires, a single vertical wire, and a single second terminal wire may also be employed.

[0065] Each light-emitting element 23 is provided between a corresponding anode wiring, i.e., any one of the first to third anode wirings 31 to 33, and a corresponding cathode wiring, i.e., any one of the plurality of cathode wirings 41. Each light-emitting element 23 emits light when a current flows between the corresponding anode wiring and the corresponding cathode wiring.

[0066] In the present disclosure, either the anode wiring or the cathode wiring having the mesh-like circuit structure as described above (first to third anode wirings 31 to 33 in FIG. 2A ) is referred to as a first terminal wiring. In contrast, the other of the anode wiring or the cathode wiring (cathode wiring 41 in FIG. 2A ) is referred to as a second terminal wiring. Furthermore, in this specification, either the anode electrode 47 or the cathode electrode 48 of the light-emitting element 23 connected to the first terminal wiring (anode electrode 47 in FIG. 2A ) is referred to as a first terminal, and the other of the anode electrode 47 or the cathode electrode 48 (cathode electrode 48 in FIG. 2A ) is referred to as a second terminal.

[0067] In this specification, a mesh-like circuit structure refers to a structure on a circuit diagram such as that shown in FIG. 2A, and in reality, the first terminal wiring is composed of at least two types of wiring that are arranged in different directions, as shown in FIG. 1A.

[0068] As will be described later, the cathode wiring may have a mesh-like circuit structure. In this case, the cathode is referred to as the first terminal, and the cathode wiring is referred to as the first terminal wiring in this specification. Furthermore, the cathode horizontal wiring and cathode vertical wiring constituting the mesh-like circuit structure are referred to as the first wiring and the second wiring, respectively, and the anode and anode wiring are referred to as the second terminal and the second terminal wiring, respectively.

[0069] [Gate Wiring 42] Each gate wiring 42 extends in the horizontal direction and is electrically connected to the gates of three transistors 24. The sources of these three transistors 24 are electrically connected to the ground wiring (GND), and the drains of these three transistors 24 are electrically connected to the same single cathode wiring 41. These three transistors 24 form one drive circuit E. Figure 2A shows 27 gate wirings 42 for 81 transistors 24.

[0070] Each drive circuit E is electrically connected to the cathodes of three light-emitting elements 23 via a single cathode wiring 41. Each drive circuit E (output stage) E is used to drive the light-emitting elements 23 to generate (output) light from the light-emitting elements 23. For example, to generate light from a certain light-emitting element 23, a predetermined signal is applied to the gate wiring 42 of the drive circuit E for that light-emitting element 23. This brings the source and drain of each transistor 24 in that drive circuit E into conduction, allowing current to flow through that light-emitting element 23. When current flows through that light-emitting element 23, light is generated from that light-emitting element 23. The light-emitting device 1 shown in FIG. 2A includes 27 drive circuits E for 81 light-emitting elements 23.

[0071] [First to Third Selection Circuits 37 to 39] The first to third selection circuits 37 to 39 are electrically connected to the first to third horizontal wirings 31a to 33a of the first to third anode wirings 31 to 33, respectively. The first selection circuit 37 is used to select the light-emitting element 23 electrically connected to the first anode wiring 31 as the light-emitting element 23 that generates light. The second selection circuit 38 is used to select the light-emitting element 23 electrically connected to the second anode wiring 32 as the light-emitting element 23 that generates light. The third selection circuit 39 is used to select the light-emitting element 23 electrically connected to the third anode wiring 33 as the light-emitting element 23 that generates light. The first to third selection circuits 37 to 39 may be electrically connected to the first to third vertical wirings 31b to 33b of the first to third anode wirings 31 to 33, respectively, instead of the first to third horizontal wirings 31a to 33a of the first to third anode wirings 31 to 33.

[0072] The first selection circuit 37 includes a transistor 37a having a source electrically connected to the power supply wiring (VDD) and a transistor 37b having a source electrically connected to the ground wiring. The drains of the transistors 37a and 37b are electrically connected to the first anode wiring 31. The first selection circuit 37 is electrically connected to each of the first capacitors 34 via the first anode wiring 31.

[0073] The transistor 37a is used to store charge in each first capacitor 34. The transistor 37b is used to discharge charge from each first capacitor 34. When a predetermined signal is applied to the gate of the transistor 37a, charge is stored in each first capacitor 34. When a predetermined signal is applied to the gate of the transistor 37b, charge is discharged from each first capacitor 34. Therefore, according to this embodiment, by selectively storing charge in the first capacitor 34 of the first to third capacitors 34 to 36 using the first selection circuit 37, it is possible to pass a current to each light-emitting element 23 electrically connected to the first anode wiring 31.

[0074] 2A , the second and third selection circuits 38, 39 have the same structure as the first selection circuit 37. Therefore, according to this embodiment, by storing charge in each second capacitor 35 by the second selection circuit 38, it is possible to pass a current to each light-emitting element 23 electrically connected to the second anode wiring 32. Furthermore, according to this embodiment, by storing charge in each third capacitor 36 by the third selection circuit 39, it is possible to pass a current to each light-emitting element 23 electrically connected to the third anode wiring 33.

[0075] [First to Third Capacitors 34 to 36] The first to third capacitors 34 to 36 are electrically connected to the first to third anode wirings 31 to 33, respectively. Each first capacitor 34 stores charge to be supplied to the light-emitting element 23 electrically connected to the first anode wiring 31. Each second capacitor 35 stores charge to be supplied to the light-emitting element 23 electrically connected to the second anode wiring 32. Each third capacitor 36 stores charge to be supplied to the light-emitting element 23 electrically connected to the third anode wiring 33. According to this embodiment, by supplying charge to each light-emitting element 23 from the first to third capacitors 34 to 36, a current can be passed through each light-emitting element 23. Each of the first to third capacitors 34 to 36 has one electrode electrically connected to one of the first to third anode wirings 31 to 33 and the other electrode electrically connected to a ground wiring.

[0076] The light-emitting device 1 includes one or more first to third capacitors 34 to 36. For example, in the circuit diagram of FIG. 2A, four sets of first to third capacitors 34 to 36 are provided near the four sides of the square-shaped light-emitting element array. Specifically, the light-emitting device 1 shown in FIG. 2A includes a first set of first to third capacitors 34 to 36 near the top side of the square, a second set of first to third capacitors 34 to 36 near the right side of the square, a third set of first to third capacitors 34 to 36 near the bottom side of the square, and a fourth set of first to third capacitors 34 to 36 near the left side of the square. These first to third capacitors 34 to 36 are examples of the first to Qth sets of capacitors of the present disclosure (Q is an integer of 2 or greater). FIG. 2A shows an example where Q is 4.

[0077] The first to third capacitors 34 to 36 of the first and third sets are electrically connected to the first to third horizontal wirings 31 a to 33 a of the first to third anode wirings 31 to 33, respectively. On the other hand, the first to third capacitors 34 to 36 of the second and fourth sets are electrically connected to the first to third vertical wirings 31 b to 33 b of the first to third anode wirings 31 to 33, respectively. As a result, the first to third capacitors 34 to 36 shown in FIG. 2A are electrically connected to the first to third anode wirings 31 to 33, respectively.

[0078] In the light-emitting device 1, the average distance between a certain light-emitting element 23 and its corresponding capacitor is set to a value close to the average distance between another light-emitting element 23 and its corresponding capacitor. For example, the light-emitting element 23 at the upper left is close to the first capacitor 34 above but far from the first capacitor 34 below. On the other hand, the light-emitting element 23 at the lower right is close to the third capacitor 36 on the right but far from the third capacitor 36 on the left. Therefore, the average distance between the light-emitting element 23 at the upper left and the four first capacitors 34 is close to the average distance between the light-emitting element 23 at the lower right and the four third capacitors 36. This is also true for the other 79 light-emitting elements 23. This makes it possible to reduce the difference in impedance between the wiring of different light-emitting elements 23 with respect to the anode wiring between each light-emitting element 23 and the corresponding multiple capacitors.

[0079] The first to third capacitors 34 to 36 are arranged around the light-emitting element array so as to surround the light-emitting element array of Fig. 1A. As shown in Fig. 1A, by arranging the first to third capacitors 34 to 36 on both sides of the row of light-emitting units arranged in one direction, the average distances between the plurality of light-emitting elements 23 and the corresponding plurality of capacitors can be made approximately equal.

[0080] 2A, the light emitting device 1 also includes a control unit 30 that individually controls the light emission of each of the plurality of light emitting elements 23. The control unit 30 controls the gate voltages of the transistors 37a, 37b, 38a, 38b, 39a, 39b, and 24 based on instructions from a distance measuring device (not shown in FIG. 2A) or signals from a temperature detection unit or voltage detection unit (not shown) in the light emitting device 1. This makes it possible to control the light emission timing, number of light emissions, light emission interval, pulse width, and the like of each light emitting element 23.

[0081] Figure 2B is a circuit diagram showing a portion of the configuration of Figure 2A. Figure 2B shows light-emitting elements 23A1 to 23C3 and cathode wirings 41a to 41c of Figure 1A. Figure 2B also shows first to third horizontal wirings 31a to 33a, first to third vertical wirings 31b to 33b, first to third selection circuits 37 to 39, and first to third capacitors 34 to 36.

[0082] 2B include transistors 24a, 24b, and 24c, respectively. Drive circuit Ea is connected to cathode wiring 41a and drives light-emitting elements 23A1 to 23A3. Drive circuit Eb is connected to cathode wiring 41b and drives light-emitting elements 23B1 to 23B3. Drive circuit Ec is connected to cathode wiring 41c and drives light-emitting elements 23C1 to 23C3.

[0083] [Operation of Light-Emitting Device 1] Figures 3A and 3B are diagrams illustrating the operation of the light-emitting device 1 according to the first embodiment of the present disclosure. The operation shown in Figures 3A and 3B is initiated, for example, when a light emission command is received from a distance measuring device (not shown). Figures 3A and 3B show, as an example, the operation when the light-emitting element 23A1 is the light-emitting target. As described above, the anode of the light-emitting element 23A1 that is the light-emitting target is connected to the first capacitor 34 and the first selection circuit 37 via the first anode wiring 31. The cathode of the light-emitting element 23A1 is connected to the drive circuit Ea via the cathode wiring 41a.

[0084] 3A is a diagram showing the charging of first capacitor 34. In first selection circuit 37, transistor 37a is turned on and transistor 37b is turned off. As a result, current flows from the power supply voltage VDD node through transistor 37a to first capacitor 34, charging first capacitor 34. At this time, a voltage close to power supply voltage VDD is applied to the anode electrode of light-emitting element 23A1, but because drive circuit Ea has turned off transistor 24a, no current flows through light-emitting element 23A1, and light-emitting element 23A1 does not emit light.

[0085] A selection circuit other than the first selection circuit 37, for example, the second selection circuit 38, is connected to the light-emitting elements 23A2 and 23B2 that are not to emit light and the second capacitor 35 via the second anode wiring 32. In the second selection circuit 38, the transistor 38a is turned off and the transistor 38b is turned on. Therefore, the charge in the second capacitor 35 is discharged via the transistor 38b to, for example, the ground voltage node.

[0086] 3B is a diagram showing the light emission of light-emitting element 23A1. After first capacitor 34 is charged, drive circuit Ea turns on transistor 24a, causing the cathode voltage of light-emitting element 23A1 to drop. This causes the charge from first capacitor 34 to be discharged, causing current to flow between the anode and cathode of light-emitting element 23A1, causing light emission from light-emitting element 23A1. The light-emission pulse width of light-emitting element 23A1 can be controlled by the amount of charge stored in first capacitor 34 and the period during which drive circuit Ea turns on transistor 24a.

[0087] The light-emitting element 23B1, which is not to emit light, is also connected to the first capacitor 34. The light-emitting element 23B1 is connected to the drive circuit Eb via the cathode wiring 41b. The drive circuit Eb turns off the transistor 24b, so the light-emitting element 23B1 does not emit light. The light-emitting elements 23A2 and 23B2 do not emit light because no charge has been stored in the second capacitor 35.

[0088] As described above, the control unit 30 can selectively cause the light emitting element 23A1 to emit light from among the light emitting elements 23A1 to 23B2.

[0089] 4 is a circuit diagram illustrating a modified example of the light-emitting device 1 according to the first embodiment of the present disclosure. The light-emitting device 1 has a switch SW1 that switches whether or not two anode wirings (e.g., the first anode wiring 31 and the second anode wiring 32) are short-circuited. By turning on the switch SW1 and shorting the first anode wiring 31 and the second anode wiring 32, the light-emitting device 1 can simultaneously select, for example, light-emitting elements 23A1 and 23A2 using a single first selection circuit 37. This allows the light-emitting elements 23A1 and 23A2 to emit light simultaneously.

[0090] The light emitting device 1 may include a switch SW2 that switches whether to short-circuit two cathode wirings (e.g., the cathode wirings 41 a and 41 b). By short-circuiting the cathode wirings 41 a and 41 b, the light emitting device 1 can control the light emission of the light emitting elements 23A1 and 23B1, for example, using a single drive circuit Ea.

[0091] The switch SW1 may short-circuit three or more anode wirings, and the switch SW2 may short-circuit three or more cathode wirings.

[0092] Fig. 5 is a graph illustrating the performance of the light-emitting device 1 according to the first embodiment of the present disclosure. The vertical axis of Fig. 5 represents the current supplied to each light-emitting element 23, and the horizontal axis of Fig. 5 represents time. Note that each light-emitting element 23 is supplied with a current (hereinafter referred to as LDD output current) from, for example, an LDD substrate (described below). Fig. 5 shows the waveform of the LDD output current. Fig. 5 further shows the peak value Ipeak of the LDD output current, the pulse width W of the LDD output current, and the half-value width W' of the LDD output current.

[0093] It is desirable to increase the peak value Ipeak and shorten the pulse width W (or half-value width W') to improve the performance of the light emitting device 1. In the light emitting device 1 according to the first embodiment, it is possible to increase the peak value Ipeak and shorten the pulse width W (or half-value width W') by reducing the impedance of each wiring or the difference in impedance between wirings.

[0094] Fig. 6 is a cross-sectional view showing an example of the cross-sectional structure of a light emitting device 1 with a VCSEL structure. The light emitting device 1 in Fig. 6 is configured, for example, by stacking an LD (Laser Diode) chip 11 on an LDD substrate 12. The LD chip 11 includes a substrate 21, a stacked film 22, a plurality of light emitting elements 23 formed using the stacked film 22, a plurality of anode electrodes 47, and a cathode electrode 48.

[0095] The substrate 21 of the LD chip 11 is made of a compound semiconductor such as GaAs (gallium arsenide). The surface of the substrate 21 facing the LDD substrate 12 is the front surface S2, and laser light is emitted from the back surface S3 of the substrate 21. The stacked film 22 includes a first multilayer reflector, a first spacer layer, an active layer, a second spacer layer, and a second multilayer reflector. The laser light generated in the active layer is resonated between the first multilayer reflector and the second multilayer reflector to increase the light intensity and is emitted from the back surface S3 of the substrate. Thus, the LD chip 11 of FIG. 6 is a back-illuminated type. In this specification, a light-emitting element 23 having the layer structure shown in FIG. 6 is referred to as a VCSEL structure.

[0096] The plurality of light-emitting elements 23 have a mesa structure formed by processing the laminated film 22 into a mesa shape. As viewed from the substrate 21 side, an anode electrode (second pad) 47 is disposed on the upper surface of each light-emitting element 23. Similarly, as viewed from the substrate 21 side, a cathode electrode 48 is disposed on the upper and side surfaces of the laminated film 22 disposed on the end side of the LD chip 11. As viewed from the substrate 21 side, a cathode electrode 48 is also disposed on the lowermost layer of the laminated film 22 of the plurality of light-emitting elements 23. In FIG. 6 , the anode electrode 47 and the cathode electrode 48 may be reversed. While the common electrode in FIG. 6 is the cathode electrode 48, the common electrode may be the anode electrode 47, and a cathode electrode 48 may be provided on each mesa portion 20.

[0097] The LDD substrate 12 has a plurality of pads 49 for supplying drive signals to the plurality of light emitting elements 23 of the LD chip 11. The pads 49 are arranged along a surface S1 of the LDD substrate 12 that faces the LD chip 11. A bonding layer 50 is arranged on these pads 49, and the pads 49 of the LDD substrate 12 are bonded to the corresponding pads of the anode electrode 47 of the LD chip 11 via the bonding layer 50. The LDD substrate 12 has a plurality of drive circuits E shown in FIG.

[0098] The substrate 21 of the LD chip 11 is, for example, a compound semiconductor substrate such as a GaAs (gallium arsenide) substrate. Fig. 6 shows a front surface S2 of the substrate 21 facing the -Z direction and a back surface S3 of the substrate 21 facing the +Z direction. The front surface S1 and back surface S2 shown in Fig. 6 are perpendicular to the Z direction. In Fig. 6, the front surface S2 is the lower surface of the substrate 21, and the back surface S3 is the upper surface of the substrate 21.

[0099] The light emitting element 23 is provided on the surface S2 of the substrate 21 as part of the laminated film 22. The light emitting element 23 of this embodiment has a VCSEL structure and emits light in the +Z direction. As shown in FIG. 6 , the light emitted from the light emitting element 23 passes through the substrate 21 from the surface S2 to the back surface S3 of the substrate 21.

[0100] Each light-emitting element 23 is provided between an anode electrode 47 and a cathode electrode 48 connected to the anode wirings 31 to 33. Each light-emitting element 23 emits light when a current flows between the anode electrode 47 and the cathode electrode 48.

[0101] At least some of the capacitors 34 to 36 connected to the first to third anode wirings 31 to 33 may be arranged so as to overlap the LD chip 11 and the LDD substrate 12 in a plan view, thereby suppressing variations in the distance between each capacitor and the light-emitting element 23 and the distance between each capacitor and the first to third selection circuits 37 to 39.

[0102] 7 is a circuit diagram showing the structure of a light emitting device 100 according to a first comparative example. Similar to the light emitting device 1 according to the first embodiment, the light emitting device 100 according to the first comparative example includes a light emitting element array including nine light emitting elements 23 arranged in one direction.

[0103] The light-emitting device 100 according to the first comparative example includes a capacitor array including nine capacitors 34 arranged in an array, and the capacitor array is arranged adjacent to the light-emitting element array. In the light-emitting device 100, the light-emitting element array and the capacitor array are arranged in one direction, with a drive circuit E arranged at one end of the light-emitting element array and the capacitor array arranged at the other end of the light-emitting element array. Each light-emitting element 23 is electrically connected to its corresponding capacitor 34 via a corresponding anode wiring 31. Furthermore, each light-emitting element 23 is electrically connected to a common drive circuit E (transistor 24) via a common cathode wiring 41.

[0104] The light-emitting device 100 according to the first comparative example has problems in that it has a large number of anode wirings 31 and that the anode wirings 31 are long on average. Another problem is that the light-emitting device 100 includes both short and long anode wirings 31. As a result, problems arise in that the impedance of each anode wiring 31 increases and that the difference in impedance between the anode wirings 31 increases. Another problem arises in that the length of the cathode wiring 41 between each light-emitting element 23 and the drive circuit E varies greatly for each light-emitting element 23.

[0105] If the impedance of each anode wiring 31 is large, the intensity of light emitted from each light-emitting element 23 may be insufficient, or the amount of power consumed to drive each light-emitting element 23 may increase. Furthermore, if the difference in impedance between the anode wirings 31 becomes large, the difference in intensity of light emitted from different light-emitting elements 23 may become large. For example, if the light-emitting device 100 is applied to a distance measuring device, the accuracy of distance measurement may decrease. Furthermore, the light-emitting device 100 according to the first comparative example requires an anode wiring for each light-emitting element 23.

[0106] In contrast, in the light-emitting device 1 according to the first embodiment, multiple capacitors are arranged around the light-emitting element array arranged in one direction. Each light-emitting element 23 is connected to multiple capacitors via multiple anode wirings. Because each light-emitting element 23 is also connected to a capacitor arranged nearby, the average distance between the light-emitting element 23 and the capacitor is shorter than in the light-emitting device 100 according to the comparative example, meaning that the length of the anode wiring can be shorter than in the light-emitting device 100. Furthermore, in the light-emitting device 1 according to the first embodiment, multiple capacitors are arranged so that the average distance between each light-emitting element 23 and its corresponding multiple capacitors is approximately the same. This allows the average length of the anode wiring for each light-emitting element 23 to be approximately the same. As a result, the light-emitting device 1 can reduce the impedance of each anode wiring and minimize the difference in impedance between each anode wiring.

[0107] 1A, the light emitting device 1 according to the first embodiment of the present disclosure requires only three anode wirings 31 to 33 for nine light emitting elements 23A1 to 23C3. In this way, the light emitting device 1 according to the first embodiment can reduce the number of anode wirings compared to the light emitting device 100 according to the first comparative example.

[0108] Furthermore, in the light emitting device 1 according to the first embodiment, the cathode wiring 41 is arranged for every three light emitting elements 23, so that the length of the cathode wiring 41 can be shortened.

[0109] As described above, the light-emitting device 1 according to the first embodiment includes the first to third anode wirings 31 to 33 and the first to third capacitors 34 to 36 arranged around the light-emitting element array arranged in one direction. Therefore, the light-emitting device 1 according to the first embodiment can suppress variations in the length of the wiring connected to each light-emitting element, and can also suppress variations in wiring capacitance and impedance between wiring. Therefore, for example, by applying the light-emitting device 1 according to this embodiment to a distance measuring device, it is possible to improve distance measurement accuracy.

[0110] Second Embodiment Fig. 8A is a layout diagram showing the configuration of a light emitting device 1a according to a second embodiment of the present disclosure. Fig. 8B is a layout diagram of a first example of the light emitting device 1a according to the second embodiment of the present disclosure. The light emitting device 1a shown in Fig. 1A includes a plurality of light emitting units 26 to 28 arranged in a direction inclined with respect to one direction U. In Figs. 1A and 1B, the longitudinal direction of each light emitting unit is arranged substantially parallel to the one direction U, but in Fig. 8A, the longitudinal direction S of each light emitting unit is arranged in a direction inclined with respect to the one direction U.

[0111] In this specification, the arrangement of the light-emitting units 26 to 28 (and the light-emitting elements 23A1 to 23C3) shown in FIG. 8A is referred to as an oblique arrangement. The circuit diagram of the light-emitting device 1a according to the second embodiment is shown in FIG. 2A. Thus, the light-emitting device according to the second embodiment has the same circuit configuration as the light-emitting device according to the first embodiment, but the arrangement direction of the light-emitting units with respect to the direction U is different from that of the first embodiment. This difference also results in a difference in the arrangement shapes of the anode horizontal wirings 31a to 33a, the anode vertical wirings 31b to 33b, and the cathode wirings 41a to 41c. For example, the anode vertical wirings 31b to 33b according to the second embodiment extend in the direction U and are not bent. The light-emitting units are arranged at regular intervals along the extension direction of the anode vertical wirings 31b to 33b.

[0112] As shown in Fig. 8B, a plurality of light-emitting unit rows may be provided, each row consisting of a plurality of light-emitting units arranged in a direction inclined with respect to the direction U. Fig. 8B shows an example in which two light-emitting unit rows 29a, 29b are arranged in a direction inclined with respect to the direction U. Fig. 8C is a layout diagram of a second example of the light-emitting device 1a according to the second embodiment of the present disclosure. As shown in Fig. 8C, the light-emitting units 26 to 28 may be provided with a plurality of light-emitting unit rows 29x, each row consisting of a plurality of light-emitting elements 23 arranged in the longitudinal direction S of each light-emitting unit.

[0113] 9 is a diagram showing the wiring structure of a light emitting device 150 according to a second comparative example. Similar to the light emitting device 1 according to the first embodiment, the light emitting device 150 according to the second comparative example has three light emitting sections 26 to 28 arranged obliquely. Each light emitting section has three light emitting elements 23.

[0114] The light-emitting device 150 according to the second comparative example includes a light-emitting element array having light-emitting elements 23A1 to 23C3 connected to a common anode wiring 31. A separate drive circuit E is connected to each of the light-emitting elements 23A1 to 23C3 via a corresponding cathode wiring 41. In FIG. 9, nine drive circuits E are arranged corresponding to the nine light-emitting elements 23A1 to 23C3. Each drive circuit E includes a transistor 24 shown in FIG. 2A. In FIG. 9, the transistor 24 is represented as a FET (field effect transistor) 24.

[0115] FIG. 10 is a diagram illustrating the wiring structure of a light-emitting device 1a according to a second embodiment of the present disclosure. As shown in FIG. 8A , the light-emitting device 1a of FIG. 10 has three first to third anode wirings 31 to 33. Three light-emitting units 26 to 28 are arranged along the direction in which these anode wirings 31 to 33 extend, and each light-emitting unit has three light-emitting elements 23. In FIG. 10 , each of the light-emitting units 26 to 28 has a cathode wiring 41 and a drive circuit E. Therefore, a single drive circuit E can control the light emission timing of all light-emitting elements 23 within a single light-emitting unit. In this way, the light-emitting device 1a according to the second embodiment does not require a drive circuit E for each light-emitting element 23, and the number of drive circuits E can be reduced compared to the light-emitting device 150 according to the second comparative example.

[0116] As described above, the light emitting device 1a according to the second embodiment has multiple anode wirings and a cathode wiring and a drive circuit E for each light emitting section, thereby reducing the number of drive circuits E. That is, the light emitting device 1a can reduce the total area of ​​the multiple drive circuits E. Therefore, the light emitting device 1a can be made smaller than the light emitting device 150 of FIG. 9, thereby reducing costs. Furthermore, since the number of drive circuits E can be reduced, the light emitting device 1a can also increase the area of ​​each drive circuit E. In this case, the light emitting device 1a can increase the area of ​​the transistor 24, thereby reducing the on-resistance of the transistor 24. This can improve the light output of each light emitting element 23.

[0117] In the light-emitting device 1 of the second embodiment, the arrangement direction of the light-emitting section (semiconductor chip), the longitudinal direction of the light-emitting section, and the arrangement direction of the multiple light-emitting elements 23 arranged in the light-emitting section are arbitrary, and various variations can be applied.

[0118] 11A is a layout diagram showing the configuration of a light emitting device 1b according to a third embodiment of the present disclosure. The light emitting device 1b shown in FIG. 11A is characterized in that a plurality of light emitting units 26 to 28 are arranged in a staggered pattern along one direction U.

[0119] The light-emitting units 26 to 28 (and light-emitting elements 23A1 to 23C3) shown in Figure 11A are arranged in a staggered pattern along one direction U. Although Figure 11A shows only three light-emitting units 26 to 28, the number of light-emitting units arranged in a staggered pattern along one direction U is arbitrary. Staggered arrangement A light-emitting device 1b according to the third embodiment has a circuit configuration similar to that of Figure 2A.

[0120] Fig. 11B is a plan view of a light-emitting section according to a first example of a light-emitting device 1b according to a third embodiment of the present disclosure. Fig. 11C is a plan view of a light-emitting section according to a second example of a light-emitting device 1b according to the third embodiment of the present disclosure. Figs. 11B and 11C show an example in which light-emitting sections 26 to 28 are arranged in a staggered pattern. In addition to the light-emitting elements 23A1 to 23C3 of Fig. 11A, Figs. 11B and 11C also show a light-emitting element 23D1 arranged in light-emitting section 26, a light-emitting element 23D2 arranged in light-emitting section 27, and a light-emitting element 23D3 arranged in light-emitting section 28.

[0121] In FIG. 11B, each of the light-emitting sections 26 to 28 has two or more light-emitting elements 23 arranged in a staggered pattern along the longitudinal direction (direction U in the example of FIG. 11B).

[0122] In FIG. 11C, each of the light-emitting sections 26 to 28 has two or more light-emitting elements 23 arranged in one or more rows along the longitudinal direction (direction U in the example of FIG. 11C).

[0123] The arrangement of the light-emitting elements 23 in Figure 11B is characterized by the fact that defocusing is not required and that there is less loss of light than the arrangement of the light-emitting elements 23 in Figure 11C. On the other hand, the arrangement of the light-emitting elements 23 in Figure 11C is characterized by the fact that slot switching (the timing of emitting irradiation light, described below) is not required and that flare is formed as a mass, making flare processing easy. Note that the longitudinal directions of the light-emitting units 26 to 28 in Figures 11B and 11C may be arranged in a direction inclined with respect to the direction U.

[0124] 11D is a plan view of a light-emitting section according to a third example of a light-emitting device 1b according to a third embodiment of the present disclosure. In FIG. 11D, each of the light-emitting sections 26-28 has two or more light-emitting elements 23 arranged in one or more rows along a direction S inclined relative to the longitudinal direction (direction U in the example of FIG. 11D). The arrangement of the light-emitting elements 23 in FIG. 11D does not require defocusing, has less light loss than the arrangement of the light-emitting elements 23 in FIG. 11C, does not require switching of slots (the timing of emitting irradiation light, described below), and forms flares as clusters, making flare processing easier. Furthermore, flare generation can be suppressed more effectively than the arrangement in FIG. 11B.

[0125] FIG. 11E is a diagram illustrating a first modified example of a light-emitting device 1b according to a third embodiment of the present disclosure. The light-emitting device 1b illustrated in FIG. 11E includes a plurality of light-emitting sections 80 arranged in a staggered pattern along the direction U. Each of the light-emitting sections 80 includes a plurality of light-emitting elements 23. While FIG. 11E illustrates an example in which the plurality of light-emitting elements 23 in each light-emitting section 80 are arranged in a staggered pattern along the direction U, the arrangement of the plurality of light-emitting elements 23 is arbitrary. Furthermore, the light-emitting device 1b includes third anode wirings in the same number as the number of light-emitting sections, and fourth anode wirings in the same number as the number of light-emitting section columns 29. The third anode wirings are either the vertical anode wirings or the horizontal anode wirings of FIG. 1A (e.g., the vertical anode wirings). The fourth anode wirings are either the vertical anode wirings or the horizontal anode wirings of FIG. 1A (e.g., the horizontal anode wirings).

[0126] The light emitting device 1b in FIG. 11E differs from the light emitting device 1b in FIG. 11A in that all the light emitting elements 23 in one light emitting section 80 are connected to the same anode vertical wiring and the same anode horizontal wiring.

[0127] 11E has two horizontal anode wirings extending in one direction U. Six light-emitting units 80 are connected to each horizontal anode wiring. Thus, the light-emitting device 1b has 12 light-emitting units 80. The light-emitting units 80 are arranged in a staggered pattern along the one direction U.

[0128] The light-emitting device 1b has twelve third anode wirings (anode vertical wirings) 81a, 81b, 81c, 81d, 81e, 81f, 81g, 81h, 81k, 81m, 81n, and 81p, and two fourth anode wirings (anode horizontal wirings) 82a and 82b. The third anode wirings and the fourth anode wirings in FIG. 11E are electrically connected (anode electrical connection) by twelve anode contacts. Each of the third anode wirings 81a to 81p is connected to one light-emitting unit 80. Each of the fourth anode wirings 82a and 82b is connected to six light-emitting units 80.

[0129] 11E, the cathode wiring 41 is arranged for each light-emitting element 23 in the light-emitting section 80. This allows the light-emitting device 1b in FIG. 11E to individually select the plurality of light-emitting elements 23.

[0130] Alternatively, in the light emitting device 1b of Fig. 11E, a plurality of light emitting elements 23 may be connected to a common cathode wiring 41. This allows the light emitting device 1b of Fig. 11E to switch whether or not each light emitting section 80 emits light.

[0131] 11F is a diagram illustrating a second modified example of the light-emitting device 1b according to the third embodiment of the present disclosure. In FIG. 11F, the number of third anode wirings is reduced. For example, in FIG. 11F, the same number of third anode wirings 81q and 81r as the number of fourth anode wirings 82a and 82b (i.e., two) are arranged. The third anode wirings and the fourth anode wirings in FIG. 11F are electrically connected at two nodes (Anode electrical connection).

[0132] 11F, the cathode wiring 41 may be arranged for each light-emitting element 23 in the light-emitting section 80. Alternatively, the cathode wiring 41 may be arranged for each of one or more light-emitting sections 80, or multiple light-emitting elements 23 may be connected to a common cathode wiring 41. In this way, the light-emitting device 1b in FIG. 11F can switch between emitting light for each of one or more light-emitting sections 80.

[0133] In the light-emitting device 1b according to the third embodiment, the light-emitting units or light-emitting elements 23 are arranged in a staggered pattern, thereby enabling the distance between two adjacent light-emitting units to be increased without reducing the total number of light-emitting units. Increasing the distance between the light-emitting units eliminates the risk of exceeding the upper output power limit imposed by the laser light safety standards, even when multiple light-emitting units are simultaneously activated. This eliminates the need to individually control the light-emitting elements 23 or selectively activate multiple light-emitting elements 23 that are far apart in order to ensure laser light safety standards, thereby simplifying light-emission control. In the light-emitting device 1b according to the third embodiment, light-emission control may be performed for each of one or more light-emitting units.

[0134] Fourth Embodiment In the first to third embodiments, the light-emitting elements 23 connected to at least one of different anode wiring or cathode wiring are individually driven to emit light (also referred to as individually driven). A plurality of light-emitting elements 23 connected to different anode wiring or cathode wiring may be simultaneously driven to emit light (also referred to as simultaneously driven). Fig. 12 is a circuit diagram showing a light-emitting device 1c according to a fourth embodiment of the present disclosure.

[0135] The light emitting device 1c shown in Fig. 12 has the same structure as the light emitting device 1 shown in Fig. 2A. Here, a method for driving the light emitting elements 23 indicated by the reference characters P1 to P6 will be described.

[0136] The light-emitting element 23 designated by symbol P1 is electrically connected to the first anode wiring 31 and the upper left cathode wiring 41. When only this light-emitting element 23 is to be driven (individual drive), only the first selection circuit 37 of the first to third selection circuits 37 to 39 is turned on, and only the drive circuit E for the upper left cathode wiring 41 is turned on. As a result, charge is accumulated only in the first capacitor 34 of the first to third capacitors 34 to 36, and only the three light-emitting elements 23 electrically connected to the upper left cathode wiring 41 are to be driven. As a result, current flows only through the light-emitting element 23 designated by symbol P1, and only this light-emitting element 23 emits light.

[0137] The light-emitting elements 23 indicated by symbols P2 to P4 are electrically connected to the first anode wiring 31 and are electrically connected to mutually different cathode wirings 41. When only these light-emitting elements 23 are to be driven (simultaneous drive), only the first selection circuit 37 of the first to third selection circuits 37 to 39 is turned on, and only the drive circuit E for these cathode wirings 41 is turned on. As a result, charge is accumulated only in the first capacitor 34 of the first to third capacitors 34 to 36, and only the nine light-emitting elements 23 electrically connected to these cathode wirings 41 are to be driven. As a result, current flows only through the light-emitting elements 23 indicated by symbols P2 to P4, and only these light-emitting elements 23 emit light.

[0138] The light-emitting elements 23 indicated by symbols P5 and P6 are electrically connected to the first and second anode wirings 31 and 32, respectively, and are also electrically connected to the same single cathode wiring 41. When only these light-emitting elements 23 are to be driven (simultaneous drive), only the first and second selection circuits 37 and 38 of the first to third selection circuits 37 to 39 are turned on, and only the drive circuit E for this cathode wiring 41 is turned on. As a result, charge is accumulated only in the first and second capacitors 34 and 35 of the first to third capacitors 34 to 36, and only the three light-emitting elements 23 electrically connected to this cathode wiring 41 are to be driven. As a result, current flows only through the light-emitting elements 23 indicated by symbols P5 and P6, and only these light-emitting elements 23 emit light.

[0139] The individual driving of the light-emitting element 23 designated by reference symbol P1 can also be applied to the other 80 light-emitting elements 23. The same applies to the simultaneous driving of the light-emitting elements 23 designated by reference symbols P2 to P6. Any number of light-emitting elements 23 may be simultaneously driven. The control of these individual driving and simultaneous driving is performed by, for example, the control unit 30.

[0140] The control unit 30 may synchronize and turn on or off the light emitting elements in each of the light emitting units 26 to 28 in Fig. 1. This allows the control unit 30 to individually control the light emission of each of the light emitting units 26 to 28.

[0141] The above-described individual driving and simultaneous driving can also be applied to the light emitting devices 1a and 1b described in the first to third embodiments or their modified examples. For example, the control unit 30 performs these controls.

[0142] Fifth Embodiment [First Example] Various modifications are possible to the circuit structure of the light emitting device 1 described in Fig. 2A etc. Fig. 13 is a circuit diagram showing a first example of a light emitting device 1d according to a fifth embodiment of the present disclosure.

[0143] The light-emitting device 1d of FIG. 13 includes first to third cathode wirings 31' to 33' in the positions of the first to third anode wirings 31 to 33 shown in FIG. 2A, multiple anode wirings 41' in the positions of the multiple cathode wirings 41, and no multiple gate wirings 42. Similarly to the first to third anode wirings 31 to 33, the first to third cathode wirings 31' to 33' each include first to third horizontal wirings 31a' to 33a' and first to third vertical wirings 31b' to 33b'. The first to third cathode wirings 31' to 33' are an example of the first terminal wiring of the present disclosure. The anode wiring 41' is an example of the second terminal wiring of the present disclosure.

[0144] Each light emitting element 23 in FIG. 13 includes a cathode electrically connected to one of the first to third cathode wirings 31' to 33', and an anode electrically connected to one of the plurality of anode wirings 41'.

[0145] The light-emitting device 1d of FIG. 13 further includes first to third transistors 61 to 63 at the positions of the first to third capacitors 34 to 36 shown in FIG. 2A, respectively. The first to third transistors 61 to 63 are, for example, N-type MOS transistors. The gates of the first to third transistors 61 to 63 are electrically connected to the first to third gate wirings 64 to 66, respectively. Each of the first to third transistors 61 to 63 has a drain electrically connected to one of the first to third cathode wirings 31′ to 33′ and a source electrically connected to a ground wiring. Each of the first to third transistors 61 to 63 forms a drive circuit E. The drive circuit E including the first to third transistors 61 to 63 is an example of the first to Rth drive circuits, respectively.

[0146] The light emitting device 1d of Fig. 13 further includes a plurality of capacitors 67 at the positions of the plurality of transistors 24 shown in Fig. 2A. Each of these capacitors 67 has one electrode electrically connected to one of the plurality of anode wirings 41' and the other electrode electrically connected to a ground wiring.

[0147] The light-emitting device 1d of FIG. 13 further includes a plurality of selection circuits 68 instead of the first to third selection circuits 37 to 39. Each selection circuit 68 is electrically connected to a corresponding anode wiring 41′. Each selection circuit 68 includes a transistor 68a having a source electrically connected to a power supply wiring and a transistor 68b having a source electrically connected to a ground wiring. The drain of the transistor 68a and the drain of the transistor 68b are electrically connected to the cathode wiring 41. Each selection circuit 68 is electrically connected to a corresponding capacitor 67 via the anode wiring 41′. The transistor 68a is, for example, a P-type MOS transistor. The transistor 68b is, for example, an N-type MOS transistor. The transistor 68a is an example of a first switch of the present disclosure. The transistor 68b is an example of a second switch of the present disclosure.

[0148] The functions of the capacitor 67, the transistor 68a, and the transistor 68b are similar to those of the first to third capacitors 34 to 36, the transistors 37a to 39a, and the transistors 37b to 39b, respectively. The transistor 68a can store charge in the corresponding capacitor 67. The transistor 68b can discharge charge from the corresponding capacitor 67. The capacitor 67 can supply charge to the light-emitting element 23 via the anode wiring 41′, thereby causing a current to flow through the light-emitting element 23.

[0149] The functions of the first to third transistors 61 to 63 and their drive circuit E are similar to those of the transistor 24 and its drive circuit E. The first to third transistors 61 to 63 can drive the light-emitting elements 23 electrically connected to the first to third cathode wirings 31′ to 33′, respectively.

[0150] The light emitting device 1d of FIG. 13 has a different structure from the light emitting devices 1 according to the first to fourth embodiments, but it is possible to achieve the same control as the light emitting devices 1 according to the first to fourth embodiments.

[0151] Second Example FIG. 14 is a circuit diagram showing a second example of a light emitting device 1d according to the fifth embodiment of the present disclosure.

[0152] The light-emitting device 1d of FIG. 14 includes first to third cathode wirings 31' to 33' at the positions of the first to third anode wirings 31 to 33 shown in FIG. 2A , a plurality of anode wirings 41' at the positions of the plurality of cathode wirings 41, and a plurality of gate wirings 42' at the positions of the plurality of gate wirings 42. Similarly to the first to third anode wirings 31 to 33, the first to third cathode wirings 31' to 33' each include first to third horizontal wirings 31a' to 33a' and first to third vertical wirings 31b' to 33b'. The first to third cathode wirings 31' to 33' are an example of first terminal wirings of the present disclosure. The anode wiring 41' is an example of second terminal wiring of the present disclosure.

[0153] Each light-emitting element 23 in FIG. 14 includes a cathode electrically connected to one of the first to third cathode wirings 31′ to 33′ and an anode electrically connected to one of the plurality of anode wirings 41′. Each transistor 24 in FIG. 14 includes a gate electrically connected to one of the plurality of gate wirings 42′, a drain electrically connected to one of the plurality of anode wirings 41′, and a source electrically connected to a power supply wiring. Each transistor 24 in this modification is, for example, a P-type MOS transistor. The first to third capacitors 34 to 36 and the first to third selection circuits 37 to 39 in FIG. 14 are electrically connected to the first to third cathode wirings 31′ to 33′, respectively.

[0154] The light emitting device 1d of FIG. 14 has a different structure from the light emitting devices 1 according to the first to fourth embodiments, but it is possible to achieve the same control as the light emitting devices 1 according to the first to fourth embodiments.

[0155] Third Example FIG. 15 is a circuit diagram showing a third example of a light emitting device 1d according to the fifth embodiment of the present disclosure.

[0156] The light emitting device 1d in Fig. 15 includes six sets of first to third capacitors 34 to 36 instead of the four sets of first to third capacitors 34 to 36 shown in Fig. 2A. The first to third capacitors 34 to 36 in Fig. 15 are disposed within the LD chip 11 (or within the LDD substrate 12 described below), and are therefore disposed near the light emitting element 23. In the light emitting device 1d in Fig. 15, each first capacitor 34 is electrically connected to one of the horizontal wirings 31a, each second capacitor 35 is electrically connected to one of the horizontal wirings 32a, and each third capacitor 36 is electrically connected to one of the horizontal wirings 33a.

[0157] The light emitting device 1d of FIG. 15 has a different structure from the light emitting devices 1 according to the first to fourth embodiments, but it is possible to achieve the same control as the light emitting devices 1 according to the first to fourth embodiments.

[0158] Fourth Example FIG. 16 is a circuit diagram showing a fourth example of a light emitting device 1d according to the fifth embodiment of the present disclosure.

[0159] The light emitting device 1d in Fig. 16 does not include the first to third capacitors 34 to 36. The light emitting device 1d in Fig. 16 stores the electric charge to be supplied to each light emitting element 23 in a parasitic capacitance, which will be described later, instead of the first to third capacitors 34 to 36.

[0160] FIG. 17 is another circuit diagram showing the structure of a fourth example of a light emitting device 1d according to the fifth embodiment of the present disclosure.

[0161] FIG. 17 shows a pair of light-emitting elements 23 and transistors 24 included in the light-emitting device 1d of FIG. 16. FIG. 17 further shows a parasitic capacitance 23' of the light-emitting element 23 and a parasitic capacitance 24' of the transistor 24. The light-emitting device 1d of FIG. 16 stores charge to be supplied to each light-emitting element 23 in these parasitic capacitances 23', 24'. This allows current to flow through each light-emitting element 23, causing each light-emitting element 23 to emit light. The storage in the parasitic capacitances 23', 24' is controlled by first to third selection circuits 37 to 39.

[0162] According to the light emitting device 1d of Figures 16 and 17, it is possible to achieve the same control as the light emitting device 1 of the first to fourth embodiments, etc., with a structure different from that of the light emitting device 1 of the first to fourth embodiments.

[0163] Fifth Example FIG. 18 is a circuit diagram showing various examples of the structure of a fifth example of a light emitting device 1d according to a fifth embodiment of the present disclosure.

[0164] A light emitting device 1d according to a fifth example of the fifth embodiment has the structure shown in Fig. 2A, similar to the light emitting device 1 according to the first embodiment. However, while each drive circuit E in Fig. 2A has the structure shown in A of Fig. 18, each drive circuit E according to the fifth example of the fifth embodiment has the structure shown in any one of B to D of Fig. 18.

[0165] The drive circuit E shown in Fig. 18B includes three transistors 24 electrically connected to a cathode wiring 41 and three transistors 25 electrically connected to these transistors 24. The transistors 24 and 25 shown in Fig. 18B are, for example, N-type MOS transistors. The gates of these transistors 24 are electrically connected to a common gate wiring 42, and the gates of these transistors 25 are electrically connected to a common gate wiring 43. The transistors 24 and 25 are examples of the first and second transistors of the present disclosure, respectively.

[0166] Each transistor 24 is used to select a light-emitting element 23 that emits light. Each transistor 25 is used as a current source. For example, to generate light from a certain light-emitting element 23, a predetermined signal is applied to the gate wiring 42 of the drive circuit E for that light-emitting element 23, and a predetermined signal (DC bias voltage) is applied to the gate wiring 43 of the drive circuit E for that light-emitting element 23. This causes the source and drain of each transistor 24 in that drive circuit E to become conductive, and also causes the source and drain of each transistor 25 in that drive circuit E to become conductive, allowing current to flow through that light-emitting element 23. In this case, each transistor 25 functions as a current source.

[0167] The drive circuit E shown in Fig. 18C includes three transistors 24 electrically connected to a cathode wiring 41. The transistors 24 shown in Fig. 18C are, for example, NPN-type bipolar transistors. In this case, the wiring 42 is a "base wiring" rather than a "gate wiring." The operation of the drive circuit E shown in Fig. 18C is similar to that of the drive circuit E shown in Fig. 18A.

[0168] The drive circuit E shown in Fig. 18D includes three transistors 24 electrically connected to a cathode wiring 41 and three transistors 25 electrically connected to these transistors 24. The transistors 24 and 25 shown in Fig. 18D are, for example, NPN-type bipolar transistors. In this case, the wirings 42 and 43 are "base wirings" rather than "gate wirings." The operation of the drive circuit E shown in Fig. 18D is similar to that of the drive circuit E shown in Fig. 18B.

[0169] The light emitting device 1d of FIG. 18 has a different structure from the light emitting devices 1 according to the first to fourth embodiments, but it is possible to achieve the same control as the light emitting devices 1 according to the first to fourth embodiments.

[0170] Sixth Example FIG. 19 is a circuit diagram showing the structure of a sixth example of a light emitting device 1d according to the fifth embodiment of the present disclosure.

[0171] 2A, the light-emitting device 1d in Fig. 19 includes first to third voltage detection circuits 71 to 73. The first voltage detection circuit 71 is electrically connected to the first horizontal wiring 31a of the first anode wiring 31 and the gate of the transistor 37a. The second voltage detection circuit 72 is electrically connected to the second horizontal wiring 32a of the second anode wiring 32 and the gate of the transistor 38a. The third voltage detection circuit 73 is electrically connected to the third horizontal wiring 33a of the third anode wiring 33 and the gate of the transistor 39a.

[0172] The first voltage detection circuit 71 detects the voltage of the first anode wiring 31 from the first horizontal wiring 31a of the first anode wiring 31. This voltage indicates the amount of charge stored in the four first capacitors 34. Therefore, the first voltage detection circuit 71 controls the gate voltage of the transistor 37a based on the voltage detected from the first anode wiring 31. For example, if the detected voltage is lower than a predetermined voltage, the transistor 37a is turned on to start storing charge. On the other hand, if the detected voltage is higher than the predetermined voltage, the transistor 37a is turned off to end storing charge. The light-emitting device 1d of FIG. 19 can change its output power by changing the value of this predetermined voltage. The value of this predetermined voltage is adjusted, for example, by the control unit 30.

[0173] Similarly, the second voltage detection circuit 72 detects the voltage of the second anode wiring 32 and controls the gate voltage of the transistor 38 a based on the detected voltage. The third voltage detection circuit 73 detects the voltage of the third anode wiring 33 and controls the gate voltage of the transistor 39 a based on the detected voltage.

[0174] FIG. 20 is a timing chart showing the operation of the light emitting device 1d of FIG.

[0175] Curves A1 and A2 represent the gate voltages of the anode-side PMOS, i.e., transistors 37a to 39a. Curve B represents the gate voltages of the anode-side NMOS, i.e., transistors 37b to 39b. Curve C represents the gate voltage of the cathode-side NMOS, i.e., transistor 24. Curves D1 and D2 represent the voltages (anode voltages) of the first to third anode wirings 31 to 32. Curves E1 and E2 represent the output currents (LDD output currents) from the LDD substrate 12 (described below) to each light-emitting element 23.

[0176] Curve A1 shows the case where the pulse width of the gate voltage of the transistors 37a to 39a is short, in which case the transistors 37a to 39a are turned off at a low anode voltage (curve D1), resulting in low-power emission (curve E1).

[0177] Curve A2 shows the case where the pulse width of the gate voltage of the transistors 37a to 39a is long, in which case the transistors 37a to 39a are turned off at a high anode voltage (curve D2), resulting in high-power emission (curve E2).

[0178] In this way, the light emitting device 1d of FIGS. 19 and 20 can freely change the output power.

[0179] Sixth Embodiment [Configuration of Light-Emitting Device] The light-emitting devices 1, 1a to 1d according to the first to fifth embodiments emit line-shaped light. The light-emitting devices 1, 1a to 1d according to the first to fifth embodiments may include a light scanning unit that scans the line-shaped light to emit light in two-dimensional directions. Fig. 21A is a diagram showing the configuration of a light-emitting device 1e according to a sixth embodiment of the present disclosure. The light-emitting device 1e according to the sixth embodiment has a light-emitting unit array 29, a light-projecting lens 251, and a light scanning unit 252.

[0180] 21B is a diagram showing the configuration of the channels of the light-emitting unit array 29. The light-emitting unit array 29 has light-emitting regions that can individually emit irradiation light for eight channels, for example, ch1 to ch8. These light-emitting regions are made up of one or more light-emitting units 80 or one or more light-emitting elements 23. These light-emitting regions are arranged in one direction U in FIG. 1A.

[0181] The light emitting device 1e can emit the irradiation light of each channel individually, that is, the light emitting device 1e can emit the irradiation light of each channel at different timings, or can emit the irradiation light of multiple channels simultaneously.

[0182] 21C is a diagram showing the light emitted from each channel. The light emitted from each channel from the light-emitting element array 29 is expanded in one direction U by the light-projecting lens 251, becoming an elongated beam of light. The light emitted from each channel is aligned in one direction U.

[0183] 21A is configured by, for example, a polygon mirror. The optical scanning unit 252 scans light emitted from the light-emitting element array 29 via a light-projecting lens 251 in a direction intersecting the one direction U (hereinafter referred to as a scanning direction V).

[0184] The light-emitting device 1e can irradiate light onto a surface extending in one direction U and the scanning direction V by using an array of light-emitting units 29 that irradiates line-shaped light extending in one direction U and an optical scanning unit 252 that scans the light emitted by the array of light-emitting units 29 in the scanning direction V.

[0185] Fig. 22 is a plan view showing a distance measuring device to which a light-emitting device 1e according to a sixth embodiment of the present disclosure is applied. Fig. 22A shows a case where the direction of the irradiated light is 30°, Fig. 22B shows a case where the direction of the irradiated light is 90°, and Fig. 22C shows a case where the direction of the irradiated light is 150°. The direction of the irradiated light in this case is represented by the angle of the emission direction relative to the incident direction of the irradiated light to the optical scanning unit 252.

[0186] The distance measuring device of FIG. 22 includes a light receiving section 261 , a reflecting mirror 262 , an exterior window 263 , and a light receiving lens 264 .

[0187] The illumination light of each channel (only the illumination light of ch1 is shown in FIG. 22 ) emitted from the light-emitting unit array 29 and expanded into a thin strip by the light-projecting lens 251 is reflected by the optical scanning unit 252, passes through the exterior window 263, and is illuminated onto a predetermined illumination range. At this time, the optical scanning unit 252 rotates in the scanning direction V around a predetermined rotation axis, so that the illumination light of each channel is scanned in the scanning direction V.

[0188] Furthermore, when the irradiation light of each channel is emitted simultaneously, the irradiation range of the irradiation light of each channel is at approximately the same position in the scanning direction V and is continuous in one direction U. That is, the irradiation ranges of the irradiation light of ch1 and the irradiation light of ch2 are adjacent in the one direction U, the irradiation ranges of the irradiation light of ch2 and the irradiation light of ch3 are adjacent in the one direction U, the irradiation ranges of the irradiation light of ch3 and the irradiation light of ch4 are adjacent in the one direction U, the irradiation ranges of the irradiation light of ch4 and the irradiation light of ch5 are adjacent in the one direction U, the irradiation ranges of the irradiation light of ch5 and the irradiation light of ch6 are adjacent in the one direction U, the irradiation ranges of the irradiation light of ch6 and the irradiation light of ch7 are adjacent in the one direction U, and the irradiation ranges of the irradiation light of ch7 and the irradiation light of ch8 are adjacent in the one direction U.

[0189] The illumination light of each channel is reflected by the object, and the incident light including the reflected light Lr passes through the exterior window 263, enters the optical scanning unit 252, and is reflected in the opposite direction to the illumination light of each channel. The incident light then passes through the return mirror 262, is collected by the light receiving lens 264, and enters the light receiving unit 261.

[0190] The light receiving unit 261 has, for example, a pixel array unit in which a plurality of pixels are arranged for each channel. For example, in the pixel array unit, eight pixels for each channel are arranged in a direction corresponding to one direction U. Therefore, in the pixel array unit, a total of 64 pixels are arranged in a direction corresponding to one direction U, and the number of unit fields of view in one direction U is 64. Incident light, including reflected light of illumination light of each channel, is incident on the pixel group of the corresponding channel.

[0191] [Control Method of Irradiated Light] FIGS. 23 and 24 are diagrams illustrating a first example of a control method of irradiated light for each channel of the light emitting device 1e.

[0192] Fig. 23 is a graph showing an example of the emission timing of the irradiated light for each channel. The horizontal axis represents time, and the vertical axis represents channel. Fig. 24 schematically shows an example of the irradiating direction of the irradiated light for each channel.

[0193] The illumination light of each channel is emitted a predetermined number of times for each unit field of view in the scanning direction V. In other words, the illumination light of each channel is emitted a predetermined number of times while the illumination light is scanned in the scanning direction V by a predetermined field angle Δθ.

[0194] For example, as shown in FIG. 24, within a unit field of view V1 having a viewing angle Δθ, the illumination light of ch1 to ch8 is emitted twice each, and within a unit field of view V2 having a viewing angle Δθ, the illumination light of ch1 to ch8 is emitted twice each.

[0195] The light receiving unit 261 receives reflected light Lr in each unit visual field in one direction U for each unit visual field in the scanning direction V. For example, the light receiving unit 261 receives reflected light Lr in 64 unit visual fields in one direction U in unit visual field V1, and receives reflected light Lr in 64 unit visual fields in one direction U in unit visual field V2.

[0196] In this example, the step of emitting irradiation light in channel order at time intervals Δt is repeated twice within a unit field of view in the scanning direction V. Specifically, ch1 irradiation light is emitted at time t1, ch2 irradiation light is emitted at time t2, ch3 irradiation light is emitted at time t3, ch4 irradiation light is emitted at time t4, ch5 irradiation light is emitted at time t5, ch6 irradiation light is emitted at time t6, ch7 irradiation light is emitted at time t7, and ch8 irradiation light is emitted at time t8. Next, at time t9, irradiation light from ch1 is emitted, at time t10, irradiation light from ch2 is emitted, at time t11, irradiation light from ch3 is emitted, at time t12, irradiation light from ch4 is emitted, at time t13, irradiation light from ch5 is emitted, at time t14, irradiation light from ch6 is emitted, at time t15, irradiation light from ch7 is emitted, and at time t16, irradiation light from ch8 is emitted.

[0197] The light receiving unit 261 may integrate, for each channel, the intensity of the incident light including the reflected light from the first irradiation light and the intensity of the incident light including the reflected light from the second irradiation light.

[0198] For example, the emission interval of the irradiated light of ch1 is time t9-time t1=8Δt. The emission interval of the irradiated light of the other channels is also 8Δt.

[0199] The longer the interval between the emission of the light from each channel, the greater the deviation in the direction of the first and second emission of the light from each channel. As a result, for example, the first and second emission of the light may be reflected by different objects, which may result in a decrease in resolution in the scanning direction V when the light-emitting device 1e is used for distance measurement. Therefore, it is desirable to shorten the interval between the emission of the light from each channel within each unit field of view in the scanning direction V.

[0200] In the following description, the period Δt that defines the emission timing of the irradiation light is referred to as a “slot.” Therefore, in this example, 16 slots are provided for each unit field of view in the scanning direction V.

[0201] Fig. 25 is a diagram illustrating a second example of a method for controlling the irradiated light of each channel of the light emitting device 1e. Similar to Fig. 23, Fig. 25 is a graph showing an example of the emission timing of the irradiated light of each channel.

[0202] In this example, the irradiation light of each channel is emitted continuously within a unit field of view in the scanning direction V. Specifically, at time t1 and time t2, the irradiation light of ch1 is emitted continuously. At time t3 and time t4, the irradiation light of ch2 is emitted continuously. At time t5 and time t6, the irradiation light of ch3 is emitted continuously. At time t7 and time t8, the irradiation light of ch4 is emitted continuously. At time t9 and time t10, the irradiation light of ch5 is emitted continuously. At time t11 and time t12, the irradiation light of ch6 is emitted continuously. At time t13 and time t14, the irradiation light of ch7 is emitted continuously. At time t15 and time t16, the irradiation light of ch8 is emitted continuously.

[0203] This allows the emission interval of the irradiation light from each channel to be shortened to Δt, and the degradation of the resolution in the scanning direction V is suppressed.

[0204] In this case, the emission interval of the irradiation light between the channels becomes large. For example, the emission interval between the second irradiation light of ch1 and the first irradiation light of ch8 is time t15 - time t2 = 13Δt. However, since the difference in emission timing between the channels is known, for example, when generating a point cloud, the influence of the difference in emission timing between the channels can be eliminated by correcting the position of the point in the scanning direction V for each channel based on the emission interval between the channels.

[0205] 26 and 27 are diagrams illustrating a third example of a method for controlling the light emitted from each channel of the light emitting device 1e.

[0206] Fig. 26 is a graph showing an example of the emission timing of the irradiated light of each channel, similar to Fig. 23. Fig. 27 is a graph showing an example of the irradiation direction of the irradiated light of each channel, similar to Fig. 24.

[0207] In the example of Figure 25, the irradiation light of each channel is emitted continuously. Also, the irradiation light of adjacent channels is emitted continuously. For example, the irradiation light of ch1 and the irradiation light of ch2 are emitted continuously. Therefore, the irradiation light may be concentrated within a narrow range. This increases the possibility that the intensity of the irradiation light per time may be limited due to the constraints of the safety standards for laser light.

[0208] In response to this, for example, as shown in FIGS. 26 and 27, the emission timing of the irradiated light of each channel is controlled.

[0209] Specifically, at times t1 and t3, ch1 irradiation light is emitted. At times t2 and t4, ch3 irradiation light is emitted. At times t5 and t7, ch2 irradiation light is emitted. At times t6 and t8, ch4 irradiation light is emitted. At times t9 and t11, ch5 irradiation light is emitted. At times t10 and t12, ch7 irradiation light is emitted. At times t13 and t15, ch6 irradiation light is emitted. At times t14 and t16, ch8 irradiation light is emitted.

[0210] As a result, compared to the example of FIG. 23, the emission interval of the irradiation light from each channel can be shortened to 2Δt, and the degradation of the resolution in the scanning direction V is suppressed.

[0211] 25, the interval between the emission of the irradiated light from each channel is extended to 2Δt. Furthermore, continuous irradiation of irradiated light from adjacent channels is prevented. As a result, concentrated irradiation of the irradiated light within a narrow range is prevented, and the possibility of limiting the intensity of the irradiated light per time due to the constraints of safety standards for laser light can be reduced.

[0212] In this example, strictly speaking, the irradiation light of adjacent channels is continuously emitted between time t4 and time t5, between time t8 and time t9, and between time t12 and time t13.

[0213] In contrast, the interval between the times when the irradiation light of adjacent channels is successively irradiated (for example, between time t4 and time t5) may be set to be longer than the interval between other times (for example, between time t1 and time t2).

[0214] Fig. 28 is a diagram illustrating a fourth example of a method for controlling the irradiated light of each channel of the light emitting device 1e. Like Fig. 23, Fig. 28 shows an example of the emission timing of the irradiated light of each channel.

[0215] Specifically, at times t1 and t3, ch1 irradiation light is emitted. At times t2 and t4, ch3 irradiation light is emitted. At times t5 and t7, ch5 irradiation light is emitted. At times t6 and t8, ch7 irradiation light is emitted. At times t9 and t11, ch2 irradiation light is emitted. At times t10 and t12, ch4 irradiation light is emitted. At times t13 and t15, ch6 irradiation light is emitted. At times t14 and t16, ch8 irradiation light is emitted.

[0216] This completely prevents the adjacent channels from being continuously irradiated with the irradiating light.

[0217] Fig. 29 is a diagram illustrating a fifth example of a method for controlling the irradiated light of each channel of the light emitting device 1e. Like Fig. 23, Fig. 29 shows an example of the emission timing of the irradiated light of each channel.

[0218] Specifically, at times t1 and t2, ch1 and ch2 irradiation lights are emitted simultaneously. At times t3 and t4, ch3 and ch4 irradiation lights are emitted simultaneously. At times t5 and t6, ch5 and ch6 irradiation lights are emitted simultaneously. At times t7 and t8, ch7 and ch8 irradiation lights are emitted simultaneously.

[0219] This allows the emission interval of the illumination light of each channel to be shortened to Δt, suppressing a decrease in resolution in the scanning direction V. Furthermore, compared to the example of FIG. 25, illumination light of all channels can be emitted in half the time. This makes it possible, for example, to narrow the field of view angle of the unit field of view and increase the resolution in the scanning direction V. Alternatively, for example, it becomes possible to increase the frame rate by increasing the scanning speed in the scanning direction V.

[0220] Fig. 30 is a diagram illustrating a sixth example of a method for controlling the irradiated light of each channel of the light emitting device 1e. Similar to Fig. 23, Fig. 30 shows an example of the emission timing of the irradiated light of each channel.

[0221] Specifically, at time t1 and time t3, ch1 and ch3 irradiation lights are emitted. At time t2 and time t4, ch2 and ch4 irradiation lights are emitted. At time t5 and time t7, ch5 and ch7 irradiation lights are emitted. At time t6 and time t8, ch6 and ch8 irradiation lights are emitted.

[0222] In this way, the irradiation light of two channels that are not adjacent to each other is emitted simultaneously. Also, similar to the examples of Figures 26 and 27, the emission interval of irradiation light of the same channel is set to 2Δt.

[0223] As a result, similarly to the examples of FIGS. 26 and 27, the reduction in resolution in the scanning direction V is suppressed, while the irradiation light is prevented from being concentrated within a narrow range.

[0224] 29, the time required for emitting irradiation light from all channels within a unit field of view in the scanning direction V can be shortened.

[0225] Fig. 31 is a diagram illustrating a seventh example of a method for controlling the irradiated light of each channel of the light emitting device 1e. Similar to Fig. 23, Fig. 31 shows an example of the emission timing of the irradiated light of each channel.

[0226] Specifically, at time t1 and time t3, ch1 and ch3 irradiation lights are emitted. At time t2 and time t4, ch5 and ch7 irradiation lights are emitted. At time t5 and time t7, ch2 and ch4 irradiation lights are emitted. At time t6 and time t8, ch6 and ch8 irradiation lights are emitted.

[0227] This prevents the adjacent channels from being continuously irradiated with light, as compared with the example of FIG.

[0228] [Modifications of Light-Emitting Device] Various modifications are possible for the configuration of the light-emitting device 1e and the method of controlling the emitted light described in Figures 21A to 31. For example, the number of channels of the light-emitting device 1e can be changed as appropriate. However, in order to achieve the effects of the sixth embodiment of the present disclosure, it is desirable that the number of channels of the light-emitting device 1e be four or more.

[0229] In the third to fourth examples and the sixth to seventh examples (Figures 26 to 31) of the irradiation light control method, examples are shown in which the emission interval of irradiation light for the same channel is set to 2Δt, but it is also possible to set the emission interval to a value other than 2Δt.

[0230] For example, if the number of channels in the light-emitting device 1e is n, by setting the emission interval of the irradiation light of each channel to be shorter than nΔt, the emission interval of the irradiation light of each channel can be shortened compared to the example of Fig. 23. Furthermore, by setting the emission interval of the irradiation light of each channel to be 2Δt or more, the irradiation light of each channel can be prevented from being emitted in a concentrated manner compared to the example of Fig. 25. That is, by setting the emission interval of the irradiation light of each channel to be 2Δt or more and less than nΔt, the light-emitting device 1e according to the sixth embodiment can achieve the effect of shortening the emission interval of the irradiation light of each channel while preventing the irradiation light of each channel from being emitted in a concentrated manner.

[0231] The sixth embodiment can also be applied to a case where the irradiation light of each channel is emitted three or more times within a unit field of view. In this case, for example, in the first to seventh examples of the irradiation light control method, the same emission method as the first two emission methods of the irradiation light of each channel may be repeatedly executed.

[0232] For example, in the examples of Figures 25 and 29, the irradiated light of each channel may be emitted m times in succession. For example, in the examples of Figures 26 to 28, 30, and 31, the irradiated light of each channel may be emitted m times, every other slot.

[0233] 26 to 28 show examples in which the channel of the irradiation light emitted in the next slot (emission timing) is set to a channel two channels away from the channel of the irradiation light emitted in the previous slot (emission timing). For example, an example is shown in which irradiation light on ch1 is emitted at time t1, and then irradiation light on ch3, which is two channels away from ch1, is emitted at time t2. However, it is also possible to emit irradiation light on a channel three or more channels away from the channel of the irradiation light emitted in the previous slot.

[0234] 29 shows an example in which two adjacent channels of irradiation light are emitted simultaneously, but it is also possible to emit three or more adjacent channels of irradiation light simultaneously.

[0235] 30 and 31 show an example in which the interval between the channels of the simultaneously emitted irradiation light is two channels. For example, at time t1, an example is shown in which irradiation light from ch1 and ch3, which is two channels away from ch1, is simultaneously emitted. However, irradiation light from channels that are three or more channels away from each other may also be emitted.

[0236] For example, in the examples of FIGS. 30 and 31, irradiation light of three or more channels that are not adjacent to each other may be emitted simultaneously.

[0237] The light emitting device 1e according to the sixth embodiment may be configured to emit the irradiation light of each channel once within a unit field of view.

[0238] The scanning method of the irradiation light is not limited to the above-mentioned example, and other methods may also be applied. For example, the light scanning unit 252 may be configured by one or more of a rotating mirror, a galvanometer mirror, a Risley prism, an MMT (Micro Motion Technology), a head spin, a MEMS (Micro-Electro-Mechanical Systems) mirror, an OPA (Optical Phased Array), a liquid crystal, and a VCSEL array scan.

[0239] In this way, the light-emitting device 1e according to the sixth embodiment can be provided with a plurality of light-emitting regions that emit irradiation light using one or more light-emitting units, etc., as shown in FIG. 1A. As shown in the first to fifth embodiments, the light-emitting device 1e can uniformize the intensity of the irradiation light of each light-emitting unit (i.e., the irradiation light of each channel). Furthermore, by controlling the emission timing of each of the plurality of light-emitting regions, the light-emitting device 1e can shorten the emission interval of the irradiation light and improve the resolution in the scanning direction V while satisfying the constraints of the safety standards for laser light.

[0240] Seventh Embodiment [Configuration of Range Finder] The light emitting devices 1, 1a to 1e according to the first to sixth embodiments can be applied to a range finder. FIG. 32 is a cross-sectional view of a ToF sensor. The ToF sensor of FIG. 32 is composed of the light emitting devices 1, 1a to 1e (hereinafter referred to as light emitting device 1) according to the first to sixth embodiments. The ToF sensor of FIG. 32 can be provided with a light receiving device, which will be described later, on the same support member. Specifically, the light emitting device 1 and the light receiving device are mounted on a common mounting substrate 13.

[0241] The light-emitting device 1 in Fig. 32 includes the LD (Laser Diode) chip 11 of Fig. 6, an LDD (Laser Diode Driver) substrate 12 including the above-described drive unit 3, a mounting substrate 13, a heat dissipation substrate 14, a correcting lens holder 15, one or more correcting lenses 16, and wiring 17. The LD chip 11 is also called a VCSEL substrate. The LD chip 11 is an example of a first substrate of the present disclosure, and the LDD substrate 12 is an example of a second substrate of the present disclosure. As shown in Fig. 32, the LD chip 11 and the LDD substrate 12 can also be arranged side by side without being stacked.

[0242] The LD chip 11 is disposed on a mounting substrate 13 via a heat dissipation substrate 14, and the LDD substrate 12 is also disposed on the mounting substrate 13. The mounting substrate 13 is, for example, a printed circuit board. A light receiving unit and a signal processing unit may also be disposed on the mounting substrate 13. The heat dissipation substrate 14 is, for example, a ceramic substrate such as an aluminum oxide substrate or an aluminum nitride substrate.

[0243] The correction lens holding portion 15 is disposed on the heat dissipation substrate 14 so as to surround the LD chip 11, and holds one or more correction lenses 16 above the LD chip 11. These correction lenses 16 are included in the above-mentioned light-emitting side optical system 5. Light emitted from the light-emitting region 2 in the LD chip 11 is corrected by these correction lenses 16 and then irradiated onto the above-mentioned subject H. Figure 32 shows, as an example, two correction lenses 16 held by the correction lens holding portion 15.

[0244] The wiring 17 is provided on the front, back, or inside of the mounting substrate 13, and electrically connects the LD chip 11 and the LDD substrate 12. The wiring 17 is, for example, a printed wiring provided on the front or back of the mounting substrate 13, or a via wiring that penetrates the mounting substrate 13. In this embodiment, the wiring 17 also passes through the inside or near the heat dissipation substrate 14.

[0245] FIG. 33 is a block diagram showing an example of the configuration of a distance measuring device 40 as an example of implementation of the light emitting device 1 according to this embodiment.

[0246] As shown in the figure, the distance measuring device 40 includes an optical emission processing unit (light emission unit) 51, a drive unit 52, a power supply circuit 53, an optical emission side optical system 54, an optical reception side optical system 55, an optical reception processing unit (light reception unit) 56, a signal processing unit 57, a control unit 58, and a temperature detection unit 59.

[0247] The light-emitting unit 51 emits light from a plurality of light sources. The light-emitting unit 51 and the light-emitting side optical system 54 correspond to the above-described light-emitting device 1. The light-emitting side optical system 54 also includes a light-projecting lens 251 and a light scanning unit 252 shown in FIG. 21A.

[0248] The driving unit 52 is configured to have a power supply circuit 53 for driving the light emitting unit 51. The power supply circuit 53 generates a power supply voltage (a driving voltage Vd, which will be described later) for the driving unit 52 based on an input voltage (an input voltage Vin, which will be described later) from, for example, a battery (not shown) or the like provided in the distance measuring device 40. The driving unit 52 drives the light emitting unit 51 based on the power supply voltage.

[0249] Light emitted from the light-emitting unit 51 is irradiated onto a subject (object) H, which is the object of distance measurement, via a light-emitting side optical system 54. The light thus irradiated is reflected from the subject H and enters the light-receiving surface of the light-receiving unit 56 via a light-receiving side optical system 55.

[0250] The light receiving unit 56 is a light receiving element such as a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor, and receives reflected light from the subject H that enters through the light receiving side optical system 55 as described above, converts the light into an electrical signal, and outputs the electrical signal. The light receiving side optical system 55 and the light receiving unit 56 are configured, for example, with a light receiving unit 261, a folding mirror 262, an exterior window 263, and a light receiving lens 264 shown in FIG. 22 . The light receiving unit 56 may be configured, for example, with a SPAD (Single Photon Avalanche Diode), an APD (Avalanche Photodiode), a high-sensitivity photodiode, or the like. The light receiving side optical system 55 and the light receiving unit 56 are collectively referred to as a light receiving device.

[0251] The light receiving unit 56 performs processes such as CDS (Correlated Double Sampling) and AGC (Automatic Gain Control) on the electrical signal obtained by photoelectrically converting the received light, and then performs A / D (Analog / Digital) conversion on the electrical signal, and outputs the resulting digital data to the signal processing unit 57 at the subsequent stage.

[0252] Furthermore, the light receiving unit 56 in this example outputs a frame synchronization signal Fs to the driving unit 52. This enables the driving unit 52 to cause the light emitting element 23 in the light emitting unit 51 to emit light at a timing according to the frame period of the light receiving unit 56.

[0253] The signal processing unit 57 is configured as a signal processor, for example, a DSP (Digital Signal Processor), etc. The signal processing unit 57 performs various signal processes on the digital signal input from the light receiving unit 56.

[0254] The control unit 58 is configured with, for example, a microcomputer having a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), etc., or an information processing device such as a DSP, and controls the drive unit 52 for controlling the light-emitting operation by the light-emitting unit 51, and controls the light-receiving operation by the light-receiving unit 56.

[0255] The control unit 58 has a function as a distance measuring unit 58a. The distance measuring unit 58a measures the distance to the subject H based on a signal input via the signal processing unit 57 (i.e., a signal obtained by receiving reflected light from the subject H). The distance measuring unit 58a in this example measures the distance to each part of the subject H in order to be able to identify the three-dimensional shape of the subject H.

[0256] The specific distance measurement method used by the distance measuring device 40 will be explained later.

[0257] The temperature detection unit 59 detects the temperature of the light emitting unit 51. The temperature detection unit 59 may be configured to detect the temperature using, for example, a diode.

[0258] In this example, information about the temperature detected by the temperature detection unit 59 is supplied to the drive unit 52, which enables the drive unit 52 to drive the light emitting unit 51 based on the temperature information.

[0259] [Range Measurement Method] The distance measurement method used in the distance measurement device 40 may be, for example, a STL (Structured Light) method or a ToF (Time of Flight) method.

[0260] The STL method is a method for measuring distance based on an image of a subject H illuminated with light having a predetermined light / dark pattern, such as a dot pattern or a grid pattern.

[0261] Fig. 34A is an explanatory diagram of the STL method. In the STL method, patterned light Lp having a dot pattern such as that shown in Fig. 22A is irradiated onto a subject H. The patterned light Lp is divided into a plurality of blocks BL, and a different dot pattern is assigned to each block BL (dot patterns are arranged not to overlap between blocks BL).

[0262] FIG. 34B is an explanatory diagram of the distance measurement principle of the STL system.

[0263] In this example, a wall W and a box BX placed in front of it are taken as subject H, and pattern light Lp is irradiated onto subject H. "G" in the drawing schematically represents the angle of view of the light receiving unit 56.

[0264] In addition, "BLn" in the figure denotes the light of a certain block BL in the pattern light Lp, and "dn" denotes the dot pattern of the block BLn projected on the light-receiving image by the light-receiving unit 56.

[0265] Here, if there is no box BX in front of the wall W, the dot pattern of the block BLn is projected at the position "dn'" in the figure in the received light image. In other words, the position at which the pattern of the block BLn is projected in the received light image differs depending on whether the box BX is present or not, and specifically, the pattern is distorted.

[0266] The STL method is a method for determining the shape and depth of the subject H by utilizing the fact that the irradiated pattern is distorted by the object shape of the subject H. Specifically, it is a method for determining the shape and depth of the subject H from the way the pattern is distorted.

[0267] When the STL system is adopted, for example, a global shutter type IR (Infrared) light receiving unit is used as the light receiving unit 56. In the case of the STL system, the distance measuring unit 58a controls the driving unit 52 so that the light emitting unit 51 emits pattern light, detects distortion of the pattern in the image signal obtained via the signal processing unit 57, and calculates the distance based on the distortion of the pattern.

[0268] Next, the ToF method is a method for measuring the distance to an object by detecting the time of flight (time difference) of light emitted from the light-emitting unit 51, reflected by the object, and reaching the light-receiving unit 56.

[0269] When the so-called direct ToF (dTOF) method is adopted as the ToF method, a SPAD (Single Photon Avalanche Diode) is used as the light receiving unit 56, and the light emitting unit 51 is pulse-driven. In this case, the distance measuring unit 58a calculates the time difference between the light emitted from the light emitting unit 51 and the light received by the light receiving unit 56, based on a signal input via the signal processing unit 57, and calculates the distance to each part of the subject H based on the time difference and the speed of light.

[0270] When the so-called indirect ToF (iTOF) method (phase difference method) is adopted as the ToF method, a light receiving unit capable of receiving, for example, IR light is used as the light receiving unit 56 .

[0271] (Application Example to a Mobile Body) The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of mobile body, such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, personal mobility, an airplane, a drone, a ship, or a robot.

[0272] FIG. 35 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a mobile object control system to which the technology according to the present disclosure can be applied.

[0273] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in Fig. 35, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside-vehicle information detection unit 12030, an inside-vehicle information detection unit 12040, and an integrated control unit 12050. Also shown as functional components of the integrated control unit 12050 are a microcomputer 12051, an audio / video output unit 12052, and an in-vehicle network I / F (interface) 12053.

[0274] The drivetrain control unit 12010 controls the operation of devices related to the drivetrain of the vehicle in accordance with various programs. For example, the drivetrain control unit 12010 functions as a control device for a drive force generating device for generating a drive force of the vehicle, such as an internal combustion engine or a drive motor, a drive force transmission mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating a braking force of the vehicle.

[0275] The body system control unit 12020 controls the operation of various devices equipped in the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as headlamps, backup lamps, brake lamps, turn signals, and fog lamps. In this case, radio waves transmitted from a portable device that serves as a key or signals from various switches can be input to the body system control unit 12020. The body system control unit 12020 receives these radio waves or signals and controls the vehicle's door lock device, power window device, lamps, etc.

[0276] The outside-vehicle information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 12031 is connected to the outside-vehicle information detection unit 12030. The outside-vehicle information detection unit 12030 causes the imaging unit 12031 to capture images outside the vehicle and receives the captured images. The outside-vehicle information detection unit 12030 may perform object detection processing or distance detection processing for people, cars, obstacles, signs, characters on the road surface, etc. based on the received images.

[0277] The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal corresponding to the amount of light received. The imaging unit 12031 can output the electrical signal as an image or as distance measurement information. The light received by the imaging unit 12031 may be visible light or invisible light such as infrared light.

[0278] The in-vehicle information detection unit 12040 detects information inside the vehicle. For example, a driver state detection unit 12041 that detects the state of the driver is connected to the in-vehicle information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that captures an image of the driver, and the in-vehicle information detection unit 12040 may calculate the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 12041, or may determine whether the driver is dozing off.

[0279] The microcomputer 12051 can calculate control target values ​​for the driving force generating device, steering mechanism, or braking device based on the information inside and outside the vehicle acquired by the outside-vehicle information detection unit 12030 or the inside-vehicle information detection unit 12040, and output control commands to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of an ADAS (Advanced Driver Assistance System), including vehicle collision avoidance or impact mitigation, following driving based on the inter-vehicle distance, vehicle speed maintenance driving, vehicle collision warning, vehicle lane departure warning, etc.

[0280] In addition, the microcomputer 12051 can perform cooperative control for the purpose of autonomous driving, which allows the vehicle to travel autonomously without relying on driver operation, by controlling the driving force generating device, steering mechanism, braking device, etc. based on information about the surroundings of the vehicle obtained by the outside vehicle information detection unit 12030 or the inside vehicle information detection unit 12040.

[0281] Furthermore, the microcomputer 12051 can output a control command to the body system control unit 12020 based on the information outside the vehicle acquired by the outside information detection unit 12030. For example, the microcomputer 12051 can control the headlamps according to the position of a preceding vehicle or an oncoming vehicle detected by the outside information detection unit 12030, and perform cooperative control aimed at preventing glare, such as switching from high beams to low beams.

[0282] The audio / video output unit 12052 transmits at least one of audio and video output signals to an output device capable of visually or audibly notifying the passengers of the vehicle or the outside of the vehicle of information. In the example of Fig. 35, the output devices are exemplified by an audio speaker 12061, a display unit 12062, and an instrument panel 12063. The display unit 12062 may include, for example, at least one of an on-board display and a head-up display.

[0283] FIG. 36 is a diagram showing an example of the installation position of the imaging unit 12031.

[0284] In FIG. 36 , a vehicle 12100 has imaging units 12101, 12102, 12103, 12104, and 12105 as the imaging unit 12031.

[0285] The imaging units 12101, 12102, 12103, 12104, and 12105 are provided, for example, at positions such as the front nose, side mirrors, rear bumper, back door, and the top of the windshield inside the vehicle cabin of the vehicle 12100. The imaging unit 12101 provided on the front nose and the imaging unit 12105 provided on the top of the windshield inside the vehicle cabin mainly acquire images of the front of the vehicle 12100. The imaging units 12102 and 12103 provided on the side mirrors mainly acquire images of the sides of the vehicle 12100. The imaging unit 12104 provided on the rear bumper or back door mainly acquires images of the rear of the vehicle 12100. The forward images acquired by the imaging units 12101 and 12105 are mainly used to detect preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, lanes, etc.

[0286] 36 shows an example of the imaging ranges of the imaging units 12101 to 12104. Imaging range 12111 indicates the imaging range of the imaging unit 12101 provided on the front nose, imaging ranges 12112 and 12113 indicate the imaging ranges of the imaging units 12102 and 12103 provided on the side mirrors, respectively, and imaging range 12114 indicates the imaging range of the imaging unit 12104 provided on the rear bumper or back door. For example, by overlaying the image data captured by the imaging units 12101 to 12104, an overhead image of the vehicle 12100 viewed from above can be obtained.

[0287] At least one of the image capturing units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the image capturing units 12101 to 12104 may be a stereo camera made up of multiple image capturing elements, or may be an image capturing element having pixels for phase difference detection.

[0288] For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 can calculate the distance to each three-dimensional object within the imaging ranges 12111 to 12114 and the change in this distance over time (relative speed with respect to the vehicle 12100), thereby extracting as a preceding vehicle, in particular, the three-dimensional object that is the closest three-dimensional object on the path of the vehicle 12100 and traveling in approximately the same direction as the vehicle 12100 at a predetermined speed (e.g., 0 km / h or higher). Furthermore, the microcomputer 12051 can set a vehicle-to-vehicle distance to be maintained in advance in front of the preceding vehicle, and perform automatic braking control (including follow-up stop control), automatic acceleration control (including follow-up start control), etc. In this way, cooperative control can be performed for the purpose of autonomous driving, which runs autonomously without relying on driver operation.

[0289] For example, the microcomputer 12051 classifies and extracts three-dimensional object data regarding three-dimensional objects into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects based on distance information obtained from the imaging units 12101 to 12104, and can use the data for automatic obstacle avoidance. For example, the microcomputer 12051 distinguishes obstacles around the vehicle 12100 into obstacles that are visible to the driver of the vehicle 12100 and obstacles that are difficult to see. The microcomputer 12051 then determines a collision risk that indicates the risk of collision with each obstacle, and when the collision risk is equal to or greater than a set value and a collision is possible, the microcomputer 12051 can provide driving assistance for collision avoidance by outputting an alarm to the driver via the audio speaker 12061 or the display unit 12062, or by performing forced deceleration or avoidance steering via the drive system control unit 12010.

[0290] At least one of the image capturing units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether a pedestrian is present in the images captured by the image capturing units 12101 to 12104. Such pedestrian recognition is performed, for example, by extracting feature points from the images captured by the image capturing units 12101 to 12104 as infrared cameras and performing pattern matching on a series of feature points that indicate the outline of an object to determine whether the object is a pedestrian. When the microcomputer 12051 determines that a pedestrian is present in the images captured by the image capturing units 12101 to 12104 and recognizes the pedestrian, the audio / image output unit 12052 controls the display unit 12062 to superimpose a rectangular outline on the recognized pedestrian for emphasis. The audio / image output unit 12052 may also control the display unit 12062 to display an icon or the like indicating the pedestrian at a desired position.

[0291] The above describes an example of a vehicle control system to which the technology according to the present disclosure can be applied. The technology according to the present disclosure can be applied to, for example, the image capture unit 12031 among the components described above. Specifically, a light-emitting device 1 according to the present disclosure can be provided together with the image capture unit 12031. By applying the technology according to the present disclosure to the image capture unit 12031, it is possible to improve the resolution of a distance image while satisfying the constraints of the safety standards for laser light, thereby enhancing the functionality and safety of the vehicle 12100.

[0292] The present technology may be configured as follows: (1) A light-emitting device comprising: a plurality of light-emitting sections arranged in one direction; a plurality of light-emitting elements, at least one of which is provided in each of the plurality of light-emitting sections, each having a first and a second terminal; M first wirings (M is an integer of 2 or more) and N second wirings (N is an integer of 2 or more), each of which intersects the M first wirings and is electrically connected to at least one of the M first wirings, a plurality of first terminal wirings electrically connected to the first terminals of the plurality of light-emitting elements; a plurality of second terminal wirings electrically connected to the second terminals of the plurality of light-emitting elements, each of which is electrically connected to P (P is an integer of 2 or more) of the light-emitting elements; a plurality of selection circuits respectively connected to one of the plurality of first terminal wirings and the plurality of second terminal wirings and selecting a corresponding one of the light-emitting elements; and a plurality of drive circuits respectively connected to the other of the plurality of first terminal wirings and the plurality of second terminal wirings and driving a corresponding one of the light-emitting elements. (2) The light-emitting device according to (1), wherein N is an integer that is the same as or different from M, and wherein P is an integer that is the same as or different from at least one of M and N. (3) The light-emitting device according to (1) or (2), further comprising a plurality of capacitors that are electrically connected to one of the first and second terminal wirings and that store electric charges for causing current to flow to the plurality of light-emitting elements. (4) The light-emitting device according to any one of (1) to (3), wherein the plurality of light-emitting units are arranged in one row or multiple rows along the one direction. (5) The light-emitting device according to (4), wherein the plurality of light-emitting units are arranged in a staggered pattern along the one direction. (6) The light-emitting device according to any one of (1) to (3), wherein the plurality of light-emitting units are arranged in a direction inclined with respect to the one direction. (7) The light-emitting device according to any one of (1) to (6), wherein the longitudinal direction of each of the plurality of light-emitting units is arranged in a direction inclined with respect to the one direction. (8) The light emitting device according to (7), wherein each of the plurality of light emitting sections has two or more of the light emitting elements arranged in one or more rows along the longitudinal direction.(9) The light-emitting device according to (8), wherein each of the plurality of light-emitting sections has two or more of the light-emitting elements arranged in a staggered pattern along the longitudinal direction. (10) The light-emitting device according to (7), wherein each of the plurality of light-emitting sections has two or more of the light-emitting elements arranged in one or more rows along a direction inclined with respect to the longitudinal direction. (11) The light-emitting device according to any one of (1) to (10), wherein the extending direction of the N second wirings is the one direction. (12) The light-emitting device according to (11), wherein each of the plurality of light-emitting sections is arranged at regular intervals along the extending direction of the N second wirings. (13) The light-emitting device according to (12), wherein the N second wirings are arranged so as to be alternately bent in a first direction inclined with respect to the one direction and a second direction intersecting the first direction, and each of the plurality of light-emitting sections is arranged in accordance with the period in which the N second wirings are bent. (14) The light-emitting device according to any one of (1) to (13), wherein each of the M first wirings is arranged so as to intersect with one or more of the light-emitting units arranged along the one direction. (15) The light-emitting device according to any one of (1) to (14), wherein each of the plurality of second terminal wirings is arranged so as to intersect with one or more of the light-emitting units arranged along the one direction. (16) The light-emitting device according to (15), wherein each of the plurality of second terminal wirings is provided corresponding to one of the plurality of light-emitting units and is connected to the second terminal of the light-emitting element in the corresponding light-emitting unit. (17) The light-emitting device according to any one of (1) to (16), further comprising a control unit that individually controls light emission of each of the plurality of light-emitting units. (18) The light-emitting device according to (17), wherein, when each of the plurality of light-emitting units has a plurality of the light-emitting elements, the control unit synchronously turns on or off the plurality of light-emitting elements.(19) A distance measuring device comprising: a light emitting device that emits light toward an object; and a distance measuring unit that receives light reflected by the object and measures the distance to the object, wherein the light emitting device comprises: a plurality of light emitting units arranged in one direction; a plurality of light emitting elements, at least one of which is provided in each of the plurality of light emitting units, each having a first and a second terminal; M first wirings (M is an integer of 2 or more) and N second wirings (N is an integer of 2 or more), each of which intersects with the M first wirings and is electrically connected to at least one of the M first wirings, a plurality of first terminal wirings electrically connected to the first terminals of the plurality of light emitting elements; a plurality of second terminal wirings electrically connected to the second terminals of the plurality of light emitting elements, each of which is electrically connected to P (P is an integer of 2 or more) of the light emitting elements; and a plurality of selection circuits respectively connected to one of the plurality of first terminal wirings and the plurality of second terminal wirings and selecting a corresponding light emitting element. a plurality of drive circuits connected to the other of the plurality of first terminal wirings and the plurality of second terminal wirings, respectively, and driving the corresponding light emitting elements, and an optical scanning unit that scans the one-directional light emitted from the plurality of light emitting units in a direction intersecting the one direction.

[0293] The aspects of the present disclosure are not limited to the individual embodiments described above, but include various modifications that may be conceived by those skilled in the art, and the effects of the present disclosure are not limited to the above-described contents. In other words, various additions, modifications, and partial deletions are possible within the scope of the conceptual idea and spirit of the present disclosure, which is derived from the contents defined in the claims and their equivalents.

[0294] REFERENCE SIGNS LIST 1, 1a, 1b, 1c, 1d, 100, 150 light emitting device, 2 light emitting region, 3 drive unit, 5 light emitting side optical system, 11 LD chip, 12 LDD substrate, 13 mounting substrate, 14 heat dissipation substrate, 15 correction lens holding unit, 16 correction lens, 17 wiring, 20 mesa portion, 21 substrate, 22 laminated film, 23, 23A1, 23A2, 23A3, 23B1, 23B2, 23B3, 23C1, 23C2, 23C3, 23D1, 23D2, 23D3 light emitting element, 23', 24' parasitic capacitance, 24, 24a, 24b, 24c, 25, 37a, 37b, 38a, 38b, 39a, 39b, 68a, 68b Transistors, 26, 27, 28, 80: light-emitting section, 29, 29a, 29b: light-emitting section row, 29x: light-emitting element row, 30: control section, 31: first anode wiring, 31': first cathode wiring, 31a, 31a': first horizontal wiring, 31b, 31b': first vertical wiring, 32: second anode wiring, 32': second cathode wiring, 32a, 32a': second horizontal wiring, 32b, 32b': second vertical wiring, 33: third anode wiring, 33': third cathode wiring, 33a, 33a': third horizontal wiring, 33b, 33b': third vertical wiring, 34: first capacitor, 35: second capacitor, 36: third capacitor, 37: first selection circuit, 38: second selection circuit, 39: third selection circuit, 40: distance measuring device, 41, 41a, 41b, 41c: cathode wiring, 41' Anode wiring, 42, 42', 43 Gate wiring, 47 Anode electrode, 48 Cathode electrode, 49 Pad, 50 Bonding layer, 51 Light-emitting processing section, 52 Drive section, 53 Power supply circuit, 54 Light-emitting side optical system, 55 Light-receiving side optical system, 56 Light-receiving processing section, 57 Signal processing section, 58 Control section, 58a Distance measuring section, 59 Temperature detection section, 61 First transistor, 62 Second transistor, 63 Third transistor, 64 First gate wiring, 65 Second gate wiring, 66 Third gate wiring, 67 Capacitor, 68 Selection circuit, 71 First voltage detection circuit, 72 Second voltage detection circuit, 73 Third voltage detection circuit, 81a, 81b, 81c, 81d, 81e, 81f, 81g, 81h, 81k, 81m, 81n, 81p, 81q, 81r Third anode wiring, 82a, 82b fourth anode wiring, 251 light projection lens, 252 optical scanning unit, 261 light receiving unit, 262 mirror, 263 exterior window, 264 light receiving lens

Claims

1. A light-emitting device comprising: a plurality of light-emitting sections arranged in one direction; a plurality of light-emitting elements, at least one of which is provided on each of the plurality of light-emitting sections, each of which has a first and a second terminal; M first wirings (M is an integer of 2 or more), and N second wirings (N is an integer of 2 or more), each of which intersects the M first wirings and is electrically connected to at least one of the M first wirings, wherein the plurality of first terminal wirings are electrically connected to the first terminals of the plurality of light-emitting elements; a plurality of second terminal wirings electrically connected to the second terminals of the plurality of light-emitting elements, each of which is electrically connected to P (P is an integer of 2 or more) of the light-emitting elements; a plurality of selection circuits respectively connected to one of the plurality of first terminal wirings and the plurality of second terminal wirings, and selecting a corresponding one of the light-emitting elements; and a plurality of drive circuits respectively connected to the other of the plurality of first terminal wirings and the plurality of second terminal wirings, and driving a corresponding one of the light-emitting elements.

2. The light emitting device according to claim 1, wherein N is an integer that is the same as or different from M, and P is an integer that is the same as or different from at least one of M and N.

3. The light emitting device according to claim 1, further comprising a plurality of capacitors electrically connected to said one of said first and second terminal wirings, said capacitors storing electric charge for causing a current to flow through said plurality of light emitting elements.

4. The light emitting device according to claim 1, wherein the plurality of light emitting sections are arranged in one row or in multiple rows along the one direction.

5. The light emitting device according to claim 4, wherein the plurality of light emitting sections are arranged in a staggered pattern along the one direction.

6. The light emitting device according to claim 1, wherein the plurality of light emitting portions are arranged along a direction inclined with respect to the one direction.

7. The light emitting device according to claim 1, wherein the longitudinal direction of each of the plurality of light emitting sections is arranged in a direction inclined with respect to the one direction.

8. The light emitting device according to claim 7, wherein each of the plurality of light emitting sections has two or more of the light emitting elements arranged in one or more rows along the longitudinal direction.

9. The light emitting device according to claim 8, wherein each of the plurality of light emitting sections has two or more of the light emitting elements arranged in a staggered pattern along the longitudinal direction.

10. The light emitting device according to claim 7, wherein each of the plurality of light emitting sections has two or more of the light emitting elements arranged in one or more rows along a direction inclined with respect to the longitudinal direction.

11. The light emitting device according to claim 1, wherein the N second wirings extend in the one direction.

12. The light emitting device according to claim 11, wherein each of the plurality of light emitting sections is arranged at regular intervals along an extension direction of the N second wirings.

13. The light-emitting device according to claim 12, wherein the N second wirings are arranged so as to be alternately bent in a first direction inclined with respect to the one direction and in a second direction intersecting the first direction, and each of the plurality of light-emitting sections is arranged in accordance with the period in which the N second wirings are bent.

14. The light emitting device according to claim 1, wherein each of the M first wirings is arranged so as to intersect with one or more of the light emitting portions arranged along the one direction.

15. The light emitting device according to claim 1, wherein each of the plurality of second terminal wirings is arranged so as to intersect with one or more of the light emitting portions arranged along the one direction.

16. The light-emitting device according to claim 15, wherein each of the plurality of second terminal wirings is provided corresponding to one of the plurality of light-emitting sections and is connected to the second terminal of the light-emitting element in the corresponding light-emitting section.

17. The light emitting device according to claim 1, further comprising a control unit that controls the light emission of each of the plurality of light emitting units individually.

18. The light-emitting device according to claim 17, wherein, when each of the plurality of light-emitting sections has a plurality of the light-emitting elements, the control section causes the plurality of light-emitting elements to light up or turn off in synchronization with each other.

19. A distance measuring device comprising: a light emitting device which emits light towards an object; and a distance measuring section which receives light reflected by the object and measures the distance to the object, the light emitting device comprising: a plurality of light emitting sections arranged in one direction; a plurality of light emitting elements, at least one of which is provided in each of the plurality of light emitting sections, each having a first and a second terminal; M first wirings (M is an integer of 2 or more) and N second wirings (N is an integer of 2 or more), each of which intersects with the M first wirings and is electrically connected to at least one of the M first wirings, a plurality of first terminal wirings electrically connected to the first terminals of the plurality of light emitting elements; a plurality of second terminal wirings electrically connected to the second terminals of the plurality of light emitting elements, each of which is electrically connected to P (P is an integer of 2 or more) of the light emitting elements; and a plurality of selection circuits respectively connected to one of the plurality of first terminal wirings and the plurality of second terminal wirings, and which select a corresponding one of the light emitting elements. a plurality of drive circuits each connected to the other of the plurality of first terminal wirings and the plurality of second terminal wirings, and each driving a corresponding one of the light-emitting elements; and a light scanning unit that scans the one-directional light emitted from the plurality of light-emitting units in a direction intersecting the one direction.

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