Light emitting device and measuring device

Abstract

The present invention reduces the number of components of a light emitting device that is capable of adjusting a plurality of light distributions. This light emitting device comprises: a light emitting unit having a first light emitting element that emits first light in a first direction, and a second light emitting element that emits second light in the first direction; and a metalens including a light-transmissive substrate and a plurality of microstructures arranged in an effective region of the substrate. The effective region of the metalens includes: a first region which is disposed in a position where the first light is incident and the second light is not incident, and in which a plurality of the microstructures are configured so as to form a first light distribution; and a second region which is disposed in a position where the first light and the second light are incident, and in which a plurality of the microstructures are configured so as to form a second light distribution different from the first light distribution.

Description

Light-emitting device, measuring device

[0001] The technology disclosed in the present specification relates to a light-emitting device and a measuring device.

[0002] With the development of AD (Autonomous Driving) and ADAS (Advanced Driver-Assistance Systems), research and development of LiDAR (Light Detection And Ranging) has been progressing as one of measuring apparatuses used for grasping the surrounding environment and estimating self-position during traveling of a vehicle. LiDAR includes a light projector that projects (irradiates) a laser beam onto a measurement target, and a light receiver that receives reflected light of the laser beam reflected back from the measurement target. LiDAR outputs information about the measurement target by measuring the distance to the measurement target based on the difference between the light projection timing at which the light projector emits the laser beam and the light reception timing at which the light receiver receives the reflected light.

[0003] Among LiDARs, LiDARs capable of adjusting a plurality of light distributions are known. Specifically, it is a LiDAR including a plurality of light projection optical systems and a plurality of light-emitting elements that emit light to each of the light projection optical systems.

[0004] Japanese Patent Application Laid-Open No. 2023-116279

[0005] Conventional LiDAR has room for improvements such as reducing the number of components.

[0006] The present specification discloses a technology capable of solving the above-described problems.

[0007] The technology disclosed in the present specification can be implemented, for example, as the following aspects.

[0008] (1) The light-emitting device disclosed herein is a light-emitting device comprising: a light-emitting unit having a first light-emitting element that emits first light in a first direction and a second light-emitting element that emits second light in the first direction; a light-transmitting substrate and a plurality of microstructures arranged in an effective region of the substrate, wherein the effective region of the metalens has a first region where the plurality of microstructures are configured to form a first light distribution, and where the first light is incident on the metalens but the second light is not incident on the first region; and a second region where the plurality of microstructures are configured to form a second light distribution different from the first light distribution, and where the first light and the second light are incident on the metalens. According to this light-emitting device, the first light emitted from the first light-emitting element and the light emitted from both the first light-emitting element and the second light-emitting element (first light and second light) pass through each region of the metalens, and the light distribution of each light emitted from each region of the metalens is different, so the light distribution of the light emitted from the light-emitting device can be easily changed.

[0009] (2) The light-emitting device may also have a third region in the effective region of the metalens, which is positioned so as to not receive the first light but receive the second light, and in which a plurality of the microstructures are configured to form a third light distribution that is different from at least one of the first light distribution and the second light distribution. With this configuration, the second light emitted from the second light-emitting element passes through the third region of the metalens, and the third light distribution of the emitted light is different from at least one of the first light distribution and the second light distribution, thereby making it possible to easily change the light distribution of the light emitted from the light-emitting device.

[0010] (3) In the above-mentioned light-emitting device, the light-emitting device described in claim 1 may be configured such that, in a second direction perpendicular to the first direction, the first light distribution angle of the first light emitted from the first region of the metalens and the second light distribution angle of the first and second light emitted from the second region of the metalens are different. With this configuration, in the second direction, the light distribution angle of the first light emitted from the first region of the metalens and the first and second light emitted from the second region of the metalens are different, making it easy to change the light distribution of the light emitted from the light-emitting device.

[0011] (4) In the above-mentioned light-emitting device, the light-emitting device according to claim 1 may have a configuration in which the light-emitting unit has a first group of light-emitting elements arranged in a third direction perpendicular to the first direction, and a second group of light-emitting elements arranged in a third direction perpendicular to the first direction, and the first region and the second region of the metalens extend in the third direction. With this configuration, by having a first light emission composed of a plurality of first light-emitting elements and a second group of light-emitting elements composed of a plurality of second light-emitting elements, a plurality of light emission patterns can be selected.

[0012] (5) The above measuring device may be configured to include a light-emitting device as described in any one of (1) to (4) above, a light-receiving receiver, and a controller. With this configuration, the measurement environment can be easily changed by mounting such a light-emitting device on the measuring device.

[0013] Furthermore, the technologies disclosed herein can be implemented in various forms, for example, in the form of a light-emitting device, a measuring device, and the like.

[0014] A block diagram schematically showing the measuring device in the embodiment. A schematic diagram showing the metalens of the first embodiment. An explanatory diagram of the light emitted from the light-emitting device in the embodiment. An explanatory diagram of the light emitted from the light-emitting device in the embodiment. An explanatory diagram of the light emitted from the light-emitting device in the embodiment.

[0015] A. Embodiments: Embodiments will be described with reference to Figures 1 to 4. Figure 1 shows mutually orthogonal X, Y, and Z axes for specifying directions. The positive X-axis direction is forward, and the negative X-axis direction is backward. The positive Y-axis direction is left, and the negative Y-axis direction is right. The positive Z-axis direction is upward, and the negative Z-axis direction is downward. Note that the positive (negative) X-axis direction is an example of a "first direction".

[0016] A-1. Configuration of the measuring device 10: Figure 1 is a schematic block diagram showing the measuring device 10 in an embodiment. The measuring device 10 in this embodiment is a LiDAR. The measuring device 10 is installed, for example, in a vehicle equipped with AD (automated drive) or ADAS (advanced driver assistance system). The measuring device 10 assists in detecting objects such as people and other vehicles while the vehicle is in motion, and provides various types of information useful for ensuring the safety of the vehicle driver and those around the vehicle, and for reducing damage to objects in the surrounding area while the vehicle is in motion, to other devices and users.

[0017] As shown in Figure 1, the measuring device 10 includes a light emitter 100, a light receiver 400, an information processing device 500, a communication interface 600, and a cover 50.

[0018] (Floodlight) The floodlight 100 comprises a light-emitting device 110 and a control circuit board 210. The light-emitting device 110 is a device that emits light. The configuration of the light-emitting device 110 will be described in detail later.

[0019] The control circuit board 210 is a circuit board on which electronic components for controlling the light emission of the light-emitting device 110 are mounted. The control circuit board 210 controls the power supply circuit (not shown) of the light-emitting device 110.

[0020] (Photodetector, etc.) As shown in Figure 1, the photodetector 400 includes a photodetecting optical system 410, a photodetector 420, and a TOF measuring device 430.

[0021] The light-receiving optical system 410 is an optical system for receiving reflected laser light Lre, which is light that has been reflected back from the measurement target W after being emitted from the light-emitting device 110 (for example, a light beam (laser light), hereinafter referred to as "emitted light Lout"), into the light-receiving unit 420. The light-receiving optical system 410 may be various lenses such as focusing lenses, various filters such as wavelength filters, or reflective mirrors.

[0022] The light-receiving unit 420 is equipped with a light-receiving element. The light-receiving element is, for example, a photodiode. The light-receiving unit 420 receives reflected laser light Lre incident from the light-receiving optical system 410, converts it into a received signal corresponding to the intensity and reception timing of the reflected laser light Lre, and outputs it.

[0023] The cover 50 protects the light-emitting device 110 and the light-receiving device 400 from the external environment. The cover 50 transmits the emitted light Lout from the light-emitting device 110. The cover 50 transmits the transmitted emitted light Lout to the outside and the reflected laser light Lre reflected from the object to be measured W. The cover 50 is positioned in front of the light-emitting device 110 and the light-receiving device 400 (positive X-axis direction). The cover 50 is, for example, a flat plate oriented in the up, down, left, and right directions (YZ plane). The cover 50 is made of a material that transmits the light emitted from the light-emitting device 110 and the reflected laser light Lre. The cover 50 is made of, for example, a transparent material (e.g., plastic).

[0024] The TOF measuring device 430 has, for example, a time measurement IC (integrated circuit) equipped with a TDC (time-to-digital converter) circuit. The TOF measuring device 430 is communicatively connected to the control circuit board 210 and the light receiving unit 420. The TOF measuring device 430 receives a timing signal indicating the light emission timing output from the control circuit board 210 and a light receiving signal output from the light receiving unit 420, and based on these, it determines the difference between the timing at which the emitted light Lout was emitted and the timing at which the reflected laser light Lre was received, that is, the time of flight (TOF) of the laser light. The TOF measuring device 430 outputs a signal corresponding to the determined TOF and the light receiving signal received from the light receiving unit 420.

[0025] The information processing device 500 has a processor. The processor may be, for example, a CPU (central processing unit), an MPU (microprocessing unit), an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), a DSP (digital signal processor), etc. The information processing device 500 is communicatively connected to the TOF measuring device 430. The information processing device 500 receives the signal corresponding to TOF output by the TOF measuring device 430 and the received signal, and generates various information such as the distance to the measurement target W based on these. This information may be, for example, a histogram used in time-correlated single photon counting, the distance to each point of the measurement target W, point cloud information, etc. The information generated by the information processing device 500 is transmitted via the communication interface 600 to an external device 700 that uses this information. The information processing device 500 is a controller.

[0026] The external device 700 may be, for example, a device that creates an environmental map using a point cloud, or a device that performs self-localization (SLAM: Simultaneous Localization and Mapping) using scan matching algorithms such as NDT (Normal Distributions Transform) and ICP (Iterative Closest Point).

[0027] A-2. Configuration of the light-emitting device 110: As shown in Figure 1, the light-emitting device 110 includes a light-emitting array 20 and a metalens 30.

[0028] (Light-emitting array 20) The light-emitting array 20 is composed of a plurality of light-emitting elements or a plurality of light-emitting element arrays (for example, in which light-emitting elements are arranged linearly (one-dimensionally) or planarly (two-dimensionally)). Each light-emitting element is, for example, a laser diode or a surface-emitting type laser light-emitting element (for example, a VCSEL (Vertical Cavity Surface Emitting Laser, hereinafter referred to as "surface-emitting element"). In this embodiment, the light-emitting array 20 is composed of a plurality of surface-emitting type laser light-emitting elements. The light-emitting elements of the light-emitting array 20 are, for example, a surface-emitting element array (for example, a VCSEL array) in which a plurality of surface-emitting elements are arranged two-dimensionally on a substrate (semiconductor substrate, ceramic substrate, etc.). Note that the light-emitting array 20 is an example of a light-emitting unit.

[0029] The light-emitting array 20 is composed of multiple rows of light-emitting elements. Each light-emitting element group has multiple light-emitting elements. The multiple light-emitting elements constituting each light-emitting element group are arranged in a line along one direction (up and down direction (Z-axis direction), hereinafter referred to as the "element arrangement direction"). The multiple rows of light-emitting elements are arranged along a direction perpendicular to the above-mentioned one direction (left and right direction (Y-axis direction), hereinafter referred to as the "group arrangement direction"). Figure 1 and Figure 3, described later, illustrate a configuration in which the light-emitting array 20 has six rows of light-emitting element groups 21, 22, 23, 24, 25, and 26.

[0030] (Metalens 30) Figure 2 is a schematic representation of the metalens 30. As shown in Figure 1, the metalens 30 is positioned between the light-emitting array 20 and the cover 50 on the optical axis of the light (L11, L21) emitted from the light-emitting array 20. As shown in Figure 2, the metalens 30 comprises a substrate 32 and a plurality of metaatoms 34 arranged on the surface of the substrate 32. Various optical properties (e.g., diffusion function, focusing function, collimation function, etc.) can be realized by appropriately designing the shape and size of the metaatoms 34 and the arrangement pattern of the metaatoms 34 on the substrate 32 (hereinafter sometimes simply referred to as "shape of metaatoms 34, etc."). In other words, a single metalens 30 can realize specific optical properties. The metaatoms 34 are an example of a microstructure.

[0031] The substrate 32 is a rectangular plate. The substrate 32 allows light emitted from the light-emitting array 20 to pass through. The surface of the substrate 32 includes a flat emission surface SO (the surface of the metalens) and a flat incidence surface SI (the surface of the metalens) located on the opposite side of the emission surface SO. An effective region Ab is provided on the emission surface SO. The material of the substrate 32 is, for example, glass, TiO ２ SiO ２ It is a synthetic resin. In this embodiment, the substrate 32 is made of glass. The thickness of the substrate 32 may be, for example, 100 nm or more and 3 mm or less.

[0032] The metaatoms 34 are positioned in the effective region Ab of the substrate 32. The metaatoms 34 are fine protrusions that project from the surface of the substrate 32. In this embodiment, the shape of the metaatoms 34 is adjusted so that the metalens 30 functions as a diffusion lens that diffuses light. The distance between adjacent metaatoms 34 is set to be sufficiently small compared to the wavelength of light incident on the metalens 30. The material of the metaatoms 34 is, for example, silicon (Si), glass, or TiO ２ SiO ２ In this embodiment, the material of the metaatom 34 is silicon with a refractive index of about 1.5 to 4. The height of the metaatom 34 from the exit surface SO may be about 1 μm or more and 2 μm or less.

[0033] The effective region Ab of the metalens 30 has multiple divided regions. The multiple divided regions are arranged along the group arrangement direction (left-right direction). The shape of each divided region is rectangular, extending in the element arrangement direction (up-down direction). In this embodiment, the shape of the metaatom 34 in each divided region is designed such that the angle of light distribution of the light incident on the divided region is converted into expanded light that is extended in one direction (for example, left-right direction) and emitted from the metalens 30. The multiple divided regions differ in at least one of the shape, size, and arrangement pattern of the metaatoms 34 placed in each divided region, such that the degree of expansion of the angle of light distribution of the light incident on each divided region differs from one another.

[0034] Figure 2 illustrates a configuration in which the effective region Ab has 11 divided regions Ab1 to Ab11. For example, the first divided region Ab1 and the second divided region Ab2 differ in at least one of the shape, size, and arrangement pattern of the metaatoms 34 placed in each divided region, such that the degree of expansion of the light distribution angle of the light incident on each divided region is different from that of the first divided region Ab1 and the second divided region Ab2.

[0035] (Relationship between the light-emitting array 20 and the metalens 30) Figure 3 is a schematic diagram showing the optical path of the first light L11 emitted from the first light-emitting group 21 in a vertical view of the light-emitting device 110. Figure 4 is a schematic diagram showing the optical path of the second light L21 emitted from the second light-emitting group 22 in a vertical view of the light-emitting device 110. Figure 5 is a schematic diagram of the optical paths of the first light L11 emitted from the first light-emitting group 21 and the second light L21 emitted from the second light-emitting group 22 in a vertical view of the light-emitting device 110. Note that Figures 3 to 5 show only the light used by the measuring device 10 when generating various information such as the distance to the measurement target W.

[0036] The multiple division regions of the metalens 30 include single division regions and overlapping division regions. A single division region is one division region corresponding to any single row (single) of light-emitting elements. Each single division region is positioned to receive light emitted from the row of light-emitting elements corresponding to that single division region. An overlapping division region is one division region corresponding to multiple adjacent light-emitting elements. Each overlapping division region is positioned to receive multiple beams of light emitted from the multiple adjacent light-emitting elements corresponding to that overlapping division region.

[0037] For example, as shown in Figure 3, the first divided region Ab1 of the metalens 30 is a single divided region and is positioned to receive only the first light L11 emitted from the first light-emitting group 21 of the light-emitting array 20. As shown in Figure 4, the third divided region Ab3 is a single divided region and is positioned to receive only the second light L21 emitted from the second light-emitting group 22. As shown in Figure 5, the second divided region Ab2 is a duplicate divided region and is positioned to receive both the first light L11 emitted from the first light-emitting group 21 and the second light L21 emitted from the second light-emitting group 22. The same relationship applies to other light-emitting groups and other divided regions. As described above, the positional relationship between the light-emitting array 20 and the metalens 30 is adjusted. Note that the first light-emitting group 21 is an example of the first light-emitting element. The second light-emitting group 22 is an example of the second light-emitting element. The first divided region Ab1 is an example of the first region. The second partitioned region Ab2 is an example of the second region. The third partitioned region Ab3 is an example of the third region.

[0038] A-3. Operation of the light-emitting device 110: For example, when the measuring device 10 is activated, the light-emitting device 110 causes the light-emitting array 20 to perform either single-shot emission or simultaneous emission. Single-shot emission means that multiple rows of light-emitting elements are emitted sequentially at different timings. Simultaneous emission means that multiple adjacent rows (two rows in this embodiment) of light-emitting elements are emitted simultaneously. The light distribution angles of the light emitted by each light-emitting element are assumed to be approximately the same.

[0039] As shown in Figure 3, for example, the light-emitting device 110 causes only the first group of light-emitting elements 21 of the light-emitting array 20 to emit light independently. The first light L11 emitted only from the first group of light-emitting elements 21 is incident on the first divided region Ab1 of the metalens 30. The first light L11 is converted by a plurality of metaatoms 34 arranged in the first divided region Ab1 to have a first light distribution. The converted first light L11 is emitted from the metalens 30 (hereinafter, the emitted light is referred to as the "first emitted light L12"). The light distribution angle of the first emitted light L12 is more diffuse than the emission angle of the first light L11. The light distribution angle of the first emitted light L12 is an example of the "first light distribution angle".

[0040] As shown in Figure 4, for example, the light-emitting device 110 causes only the second light-emitting element group 22 of the light-emitting array 20 to emit light independently. The second light L21 emitted only from the second light-emitting element group 22 is incident on the third divided region Ab3 of the metalens 30. The second light L21 is converted by a plurality of meta-atoms 34 arranged in the third divided region Ab3 to have a second light distribution. The converted second light L21 is emitted from the metalens 30 (hereinafter, the emitted light is referred to as the "second emitted light L22"). The light distribution angle of the second emitted light L22 is more diffuse than the emission angle of the second light L21. Note that the light distribution angle of the second emitted light L22 is an example of the "second light distribution angle".

[0041] As shown in FIG. 5, for example, the light-emitting device 110 causes the first light-emitting element group 21 and the second light-emitting element group 22 of the light-emitting array 20 to emit light simultaneously. The first light L11 emitted from the first light-emitting element group 21 and the second light L21 emitted from the second light-emitting element group 22 enter the second divided region Ab2 of the metalens 30. The first light L11 and the second light L21 are converted into a third light distribution by the plurality of meta-atoms 34 arranged in the second divided region Ab2. The converted first light L11 and second light L21 are emitted from the metalens 30 (hereinafter, the emitted light is referred to as "third emitted light L32"). The light distribution angle of the third emitted light L32 is more diffused than both the emission angle of the first light L11 and the emission angle of the second light L21. The light distribution angle of the third emitted light L32 is an example of the "third light distribution angle". The first emitted light L12, the second emitted light L22, and the third emitted light L32 are the aforementioned output light Lout.

[0042] The horizontal light distribution angle of the first emitted light L12, which is single-emission light, is larger than the horizontal light distribution angle of the third emitted light L32, which is simultaneous emission light. On the cover 50, the horizontal width W1 of the irradiation range of the first emitted light L12 is longer than the horizontal width W3 of the irradiation range of the third emitted light L32. On the other hand, the vertical light distribution angle of the first emitted light L12 and the vertical light distribution angle of the third emitted light L32 are the same. On the cover 50, the vertical width of the irradiation range of the first emitted light L12 is the same as the vertical width of the irradiation range of the third emitted light L32 (not shown). That is, on the cover 50, the irradiation range of the first emitted light L12 extends in the horizontal direction beyond the irradiation range of the third emitted light L32. As described above, the aspect ratio of the irradiation range of the first emitted light L12 of the light-emitting device 110 is different from the aspect ratio of the irradiation range of the third emitted light L32.

[0043] Furthermore, the left-right beam angle of the first emitted light L12, which is a single emission, is greater than the left-right beam angle of the second emitted light L22, which is also a single emission. In cover 50, the left-right width W1 of the irradiation range of the first emitted light L12 is longer than the left-right width W2 of the second emitted light L22. On the other hand, the up-down beam angle of the first emitted light L12 is the same as the up-down beam angle of the second emitted light L22. In cover 50, the up-down width of the irradiation range of the first emitted light L12 is the same as the up-down width of the irradiation range of the second emitted light L22 (not shown). That is, in cover 50, the irradiation range of the first emitted light L12 extends more in the left-right direction than the irradiation range of the second emitted light L22. Thus, the aspect ratio of the irradiation range of the first emitted light L12 of the light-emitting device 110 and the aspect ratio of the irradiation range of the second emitted light L22 are different.

[0044] The information processing device 500 of the measuring device 10 selects a light received signal from the light receiver 400 that corresponds to the light distribution pattern of the light emitted from the light emitter 110. Based on the selected light received signal, the information processing device 500 generates various information, such as the distance to the object to be measured W.

[0045] A-4. Effects of this embodiment: As described above, the light-emitting device 110 of this embodiment can form multiple types of light distribution patterns. The light-emitting device 110 forms multiple light distribution patterns from a single light-emitting optical system, the metalens 30, by using a metalens 30 having multiple divided regions. The light-emitting device 110 of this embodiment comprises a light-emitting array 20 having six rows of light-emitting elements and a metalens 30 having eleven divided regions. The light-emitting device 110 can form eleven types of light distribution patterns. As a result, the number of components that make up the light-emitting device 110 can be reduced. The light-emitting device 110 can be miniaturized.

[0046] When the measuring device 10 including the light emitting device 110 is mounted on a vehicle, the light emitting device 110 performs single light emission that emits only the first light L11 from the first light emitting element group 21, for example, when monitoring a wide area. Since the first light distribution of the first light L11 spreads in the left-right direction, the measuring device 10 can measure a wide range. On the other hand, when monitoring a specific area, the light emitting device 110 performs single light emission that emits the second light L21 from the second light emitting element group 22, for example. Since the second light distribution of the second light L21 does not spread in the left-right direction, the measuring device 10 can measure a specific target object in detail. The load on the light receiving side can be reduced, and the power consumption of the measuring device 10 can be suppressed. Furthermore, when monitoring a specific area in detail, the light emitting device 110 emits the first light L11 from the first light emitting element group 21 and emits the second light L21 from the second light emitting element group 22 simultaneously, for example, to perform simultaneous light emission. Since the third light distribution formed by the first light L11 and the second light L21 does not spread further in the left-right direction than the second light distribution, the measuring device 10 can measure a specific target object in detail.

[0047] B. Modifications: The technology disclosed in the present specification is not limited to the above-described embodiments, and can be modified into various forms without departing from the gist thereof. For example, the following modifications are also possible.

[0048] In the above embodiment, a FLASH type LiDAR is taken as an example of the measuring device 10 for description, but the present invention is not limited thereto. For example, a scan type LiDAR may be used, or an optical measuring device 10 other than LiDAR may be used.

[0049] In the above embodiment, the light emitting element is configured to include an LED, but the present invention is not limited thereto, and the light emitting element may be configured to include other semiconductor light emitting elements or light sources such as electric bulbs. Further, although each light emitting element of each light emitting element group is the same light emitting element, they do not have to be the same.

[0050] In the above embodiment, the light emitting array 20 has six rows of light emitting element groups in the left-right direction, but the number of rows is not limited to six. For example, the light emitting array 20 may have five rows of light emitting element groups, seven rows of light emitting element groups, or seven or more rows of light emitting element groups.

[0051] In the above embodiment, the multiple light-emitting element groups are positioned in the left-right direction with respect to the light-emitting array 20, but this does not have to be the case. For example, the multiple light-emitting element groups may be positioned in the up-down direction with respect to the light-emitting array 20. Furthermore, the multiple light-emitting element groups may be positioned in different directions, as long as these directions are perpendicular to the front-back direction. Each of these directions is just one example of a third direction and a fourth direction.

[0052] In the above embodiment, the multiple light-emitting elements of the light-emitting element group are arranged in a single row in the vertical direction relative to the light-emitting array 20, but they do not have to be in a single row. For example, the multiple light-emitting elements may be arranged in two or more rows.

[0053] In the above embodiment, each light-emitting element constituting the group of multiple light-emitting elements is emitted at a different timing, but they may be emitted simultaneously.

[0054] In the above embodiment, the shape and size of the metaatom 34 are adjusted so that the metalens 30 functions as a diffusion lens that diffuses light. However, the shape and size of the metaatom 34 may be adjusted so that it functions as a focusing lens or a collimating lens instead of a diffusion lens. In the above embodiment, the metaatom 34 was placed on the exit surface SO of the substrate 32. However, the metaatom 34 may also be placed on the incident surface SI of the substrate 32.

[0055] In the above embodiment, both the incident surface SI and the exit surface SO of the substrate 32 were flat surfaces. However, one of the incident surface SI and the exit surface SO may be flat, a portion of the incident surface SI may be flat, a portion of the exit surface SO may be flat, and the entire incident surface SI and exit surface SO do not have to be flat. The incident surface SI and the exit surface SO may be curved surfaces, for example. The effective area is not limited to the central region of the substrate 32, but may be a region offset from the center. The effective area is not limited to a portion of the surface of the substrate 32, but may be the entire surface. Among the plurality of metaatoms 34 arranged on the substrate 32, the cross-section of only some of the metaatoms 34 may be elongated in a predetermined direction.

[0056] In the above embodiment, the metalens 30 has six divided regions as shown in Figure 2, but it does not have to have six divided regions. For example, the metalens 30 may have five divided regions, seven divided regions, or seven or more divided regions. Also, the number of light distribution patterns of the measuring device 10 increases depending on the number of divided regions of the metalens.

[0057] In the above embodiment, the overlapping division region of the metalens 30 corresponds to two adjacent rows of light-emitting elements, but it may also correspond to three or more rows of light-emitting elements. In that case, the light-emitting device 110 simultaneously emits light from three or more rows of light-emitting elements in the light-emitting array 20.

[0058] In the above embodiment, the left-right light distribution angle of the first emitted light L12 in the light-emitting device 110 is greater than the left-right light distribution angle of the third emitted light L32, and the up-down light distribution angle of the first emitted light L12 and the up-down light distribution angle of the third emitted light L32 are the same, but the device is not limited to this. Also, in the above embodiment, the aspect ratio of the first light distribution and the aspect ratio of the third light distribution were different, but they may be the same.

[0059] In the above embodiment, in the light-emitting device 110, the left-right beam angle of the first emitted light L12 is greater than the left-right beam angle of the third emitted light L32, and the up-down beam angle of the first emitted light L12 and the up-down beam angle of the third emitted light L32 are the same. However, the up-down beam angle of the third emitted light L32 can be made smaller than the up-down beam angle of the first emitted light L12. As a result, the third beam pattern is narrower than the first beam pattern. On the other hand, the third beam pattern can illuminate a greater distance than the first beam pattern. The measuring device 10 can measure the object W located at a distance by selecting simultaneous emission.

[0060] In the above embodiment, the cover 50 is positioned in front of the light-emitting device 110 and the light-receiving device 400, but it may also be positioned only in front of the light-emitting device 110. In that case, a separate cover may be provided for the light-receiving device 400. Also, in the above embodiment, the cover 50 is made of a transparent material, but it may be made of other materials as long as it transmits the emitted light Lout. Furthermore, the cover 50 has a shape that widens vertically, but it does not have to be flat; it may be curved.

[0061] In the above embodiment, the light-emitting device may be, for example, a LiDAR used in an in-vehicle autonomous driving system (AD) or advanced driver assistance system (ADAS), or a measuring device used in a system other than AD or ADAS. The light-emitting device 110 may be a device provided in a different device or component than the measuring device 10, for example, a light-emitting device 110 provided in an in-vehicle camera. The light-emitting device 110 may be a device provided in a component for a different purpose than that of a vehicle, for example, a light-emitting device 110 provided in a security camera or a light-emitting device 110 provided in a smartphone camera.

[0062] This international application claims priority based on Japanese Patent Application No. 2025-046583, filed on 21 March 2025, and the entire contents of said Japanese Patent Application No. 2025-046583 are incorporated herein by reference.

[0063] The above description of specific embodiments of the present invention is provided for illustrative purposes only. It is not intended to be exhaustive or to limit the invention to the forms described. Numerous modifications and changes are possible in light of the above description, as will be obvious to those skilled in the art.

[0064] 10: Measuring device 20: Light-emitting array 21: First light-emitting group 22: Second light-emitting group 30: Metalens 32: Substrate 34: Metaatom 50: Cover 100: Light projector 110: Light-emitting device 210: Control circuit board 400: Light receiver 410: Light-receiving optical system 420: Light-receiving unit 430: TOF measuring device 500: Information processing device 600: Communication interface 700: External device Ab1: First divided region Ab2: Second divided region Ab3: Third divided region Ab: Effective region L11: First light L12: First emitted light L21: Second light L22: Second emitted light L32: Third emitted light Lout: Emitted light Lre: Reflected laser light SI: Incident surface SO: Emitting surface W: Target of measurement

Claims

1. A light-emitting device comprising: a light-emitting unit having a first light-emitting element that emits first light in a first direction and a second light-emitting element that emits second light in the first direction; and a metalens having a light-transmitting substrate and a plurality of microstructures arranged in an effective region of the substrate, wherein the effective region of the metalens has a first region arranged at a position where the first light is incident but the second light is not, and where a plurality of the microstructures are configured to form a first light distribution; and a second region arranged at a position where the first light and the second light are incident, and where a plurality of the microstructures are configured to form a second light distribution different from the first light distribution.

2. A light-emitting device according to claim 1, further comprising a third region in the effective region of the metalens, wherein a plurality of the microstructures are configured to form a third light distribution that is different from at least one of the first and second light distributions, and is positioned so as to not receive the first light but receives the second light.

3. A light-emitting device according to claim 1, wherein, in a second direction perpendicular to the first direction, the first beam angle of the first light emitted from the first region of the metalens and the second beam angle of the first and second light emitted from the second region of the metalens are different.

4. A light-emitting device according to claim 1, wherein the light-emitting unit has a first group of light-emitting elements arranged in a plurality of the first light-emitting elements and a second group of light-emitting elements arranged in a plurality of the second light-emitting elements in a third direction perpendicular to the first direction, and the first region and the second region of the metalens extend in the third direction.

5. A measuring device comprising a light-emitting device according to any one of claims 1 to 4, a light-receiving device, and a controller.

Images