Lidar system, optical component, reflection amplification light guide element, position detecting sensor, and mobile body

Abstract

The objective of the present technology is to improve measuring accuracy in a light detection and ranging (LiDAR) system that utilizes light to measure the distance to an object or the shape of an object. As a result of extensive research, the inventors of the present invention found that by providing a reflection amplification light guide element between a light source and an optical system in a LiDAR system, the distribution of light can be made uniform without being limited by the distance to the target object. This was found to reduce variation in signal strength between measurement points and improve measuring accuracy.

Description

LiDAR system, optical component, reflective amplification light guide element, position detection sensor, and moving object

[0001] The present technology relates to a LiDAR system, an optical component, a reflection-amplifying light-guiding element, a position detection sensor, and a moving object. More particularly, the present technology relates to a LiDAR system including a light source, a collimating optical element, a focusing optical element, and a photodetector.

[0002] Conventionally, technology relating to a LiDAR system including a light source, a collimating optical element, a focusing optical element, and a photodetector has been known.

[0003] For example, Non-Patent Document 1 below discloses a technology related to a LiDAR system that includes a light source, a collimating optical element, a focusing optical element, and a photodetector.

[0004] Temporal and Spatial Focusing in SPAD-Based Solid-State Pulsed Time-of-Flight Laser Range Imaging (Sensors 2020, 20, 5973; doi:10.3390 / s20215973)

[0005] The main purpose of this technology is to improve the measurement accuracy in a LiDAR (light detection and ranging) system that uses light to measure the distance to an object and the shape of the object.

[0006] As a result of extensive research, the inventors discovered that by providing a reflective amplification light-guiding element between the light source and the optical system in a LiDAR system, the light distribution can be made uniform regardless of the distance to the target object, thereby reducing the variation in signal strength at each measurement point and improving measurement accuracy.

[0007]

[0006] In other words, the present technology provides a LiDAR system including: a light source having a light-emitting surface composed of one or more light-emitting elements; a collimating optical element arranged on an optical axis of the light source; a reflective amplifying light-guiding element arranged on the optical axis of the light source between the light source and the collimating optical element, the reflective amplifying light-guiding element having an incident surface, a light guide path, and an output surface; a focusing optical element that focuses reflected light from an object to be measured; and a photodetector arranged on the optical axis of the focusing optical element, the photodetector having a light detection surface composed of one or more light-receiving elements, the reflective amplifying light-guiding element reflecting light incident on the incident surface within the light guide path to guide the light to the collimating optical element. In the LiDAR system of the present technology, it is preferable that the tilt angle formed by the normal to the incident surface of the reflective amplifying light-guiding element and the side surface of the light guide path is smaller than the diffraction angle of the light incident on the incident surface. Furthermore, it is preferable that the reflective amplifying light-guiding element has two or more regions made of materials with different refractive indices, and the two or more regions may be formed continuously over at least a portion of the longitudinal range of the light guide along the light guiding direction. In this case, it is preferable that at least one of the two or more regions comprises two or more cylindrical portions over at least a portion of the longitudinal range of the light guide along the light guiding direction. Also, at least one of the two or more regions may be formed continuously over the entire longitudinal range of the light guide. In the LiDAR system of the present technology, the light guide may be formed by connecting two or more portions along the light guiding direction, the inclination angle formed between the normal to the incident surface and the side surface of the light guide being different from each other. Also, the inclination angle formed between the normal to the incident surface and the side surface of the light guide may change along the light guiding direction. In the LiDAR system of the present technology, the output surface of the reflective amplifying light-guiding element may be disposed at a focal point of the collimating optical element. In the LiDAR system of the present technology, the light source and the reflective-amplifying light-guiding element may be in contact with each other at the incident surface. In the LiDAR system of the present technology, one or more adjustment media having the same refractive index may be filled between the light source and the incident surface of the reflective-amplifying light-guiding element on the optical axis of the light source.In this case, it is preferable that the refractive index of the adjustment medium is between the equivalent refractive index of the light source and the refractive index of a material that forms the light guide path and that has the lowest refractive index. In the LiDAR system of the present technology, the area of ​​the light-emitting surface that emits light from the light source and the area of ​​the incident surface may be approximately the same.

[0008] In the LiDAR system of the present technology, the area of ​​the output surface of the reflective amplifying light-guiding element may be larger than the area of ​​the incident surface. In this case, the area of ​​the light-emitting surface that emits light from the light source and the area of ​​the incident surface may be approximately the same. In this case, the area of ​​the output surface may be designed so that the range over which the reflected light is collected by the collecting optical element is approximately the same as the area of ​​the light detection surface. In the LiDAR system of the present technology, when the area of ​​the output surface of the reflective amplifying light-guiding element is larger than the area of ​​the incident surface, the reflective amplifying light-guiding element may have a tapered shape.

[0009] Next, the present technology provides an optical component for use in a LiDAR system, including a light source having a light-emitting surface composed of one or more light-emitting elements, and a reflective amplifying light-guiding element arranged on the optical axis of the light source, the reflective amplifying light-guiding element having an incident surface, a light guide path, and an output surface, where the reflective amplifying light-guiding element guides light in a specific direction by reflecting light incident on the incident surface from the light source within the light guide path. The present technology also provides a reflective amplifying light-guiding element for use in a LiDAR system, having an incident surface, a light guide path, and an output surface, where the reflective amplifying light-guiding element guides light in a specific direction by reflecting light incident on the incident surface within the light guide path. The present technology also provides a position detection sensor including the LiDAR system of the present technology. The present technology also provides a mobile object including the position detection sensor of the present technology.

[0010] 1 is an image diagram of a LiDAR system according to the present technology. FIG. 1 is an image diagram of a LiDAR system according to a conventional technology. FIG. 2 is a diagram schematically illustrating an example of the overall configuration of a LiDAR system according to the present technology. FIG. 2 is an image diagram showing an example of a LiDAR system according to a first embodiment. FIG. 3 is an image diagram showing an example of a LiDAR system according to a second embodiment. FIG. 4 is an image diagram showing how a reflection-amplifying light-guiding element used in the LiDAR system according to the second embodiment guides light. FIG. 4 is an image diagram showing a modified example of the LiDAR system according to the second embodiment. FIG. 5 is an image diagram showing an example of a LiDAR system according to a third embodiment. FIG. 6 is an image diagram showing an example of a LiDAR system according to a fourth embodiment. FIG. 7 is an image diagram showing light guiding within a light guide path taking into account the relationship between the diffraction angle of light incident on an incident surface of a reflection-amplifying light-guiding element of the present technology and the inclination angle formed between a normal to the incident surface and a side surface of the light guide path. FIG. 8 is an image diagram showing the relationship between the range of light focused by a focusing optical element provided in the LiDAR system and the area of ​​the light detection surface of a photodetector. FIG. 9 is an image diagram showing an example of a LiDAR system according to a fifth embodiment. 10 is an image diagram showing a modified example of a LiDAR system according to a fifth embodiment. FIG. 10 is an image diagram showing an example of a LiDAR system according to a sixth embodiment. FIG. 10 is an image diagram showing a modified example of a LiDAR system according to a sixth embodiment. FIG. 10 is an image diagram showing a modified example of a LiDAR system according to a seventh ... state in which a reflection-amplifying light-guiding element used in a LiDAR system according to a seventh embodiment guides light. FIG. 10 is an image diagram showing an example of an embodiment of a position detection sensor including a LiDAR system of the present technology. FIG. 10 is an image diagram showing the periphery of a light source in a position detection sensor including a LiDAR system of the present technology when an output surface of a reflection-amplifying light-guiding element is disposed at the focus of a collimating optical element. FIG. 10 is an image diagram showing an emission surface of a light source and an optical detection surface of a photodetector in a position detection sensor including a LiDAR system of the present technology. FIG. 10 is a block diagram showing an example of a schematic configuration of a vehicle control system. FIG. 10 is an explanatory diagram showing an example of installation positions of an outside vehicle information detection unit and an imaging unit.

[0011] Preferred embodiments of the present technology will be described below. However, the embodiments shown below are examples of typical embodiments of the present technology, and the present technology is not limited to only the preferred embodiments below and can be freely modified within the scope of the present technology.

[0012] [LiDAR System] The LiDAR system according to the present technology includes a light source having a light-emitting surface consisting of one or more light-emitting elements, a collimating optical element arranged on the optical axis of the light source, a reflective amplifying light-guiding element arranged on the optical axis of the light source between the light source and the collimating optical element and having an incident surface, a light guide path, and an output surface, a focusing optical element that focuses reflected light from an object to be measured, and a photodetector arranged on the optical axis of the focusing optical element and having a light detection surface consisting of one or more light-receiving elements (Toruume), and (Toruume).

[0013] The LiDAR system of the present technology arranges a reflective amplification light-guiding element between the light source and the collimating optical element on the optical axis of the light source, and reflects light incident on the incident surface of the reflective amplification light-guiding element within the light guide path of the reflective amplification light-guiding element, thereby suitably guiding light with a uniform intensity distribution to the collimating optical element. This makes it possible to uniformize the light distribution without being limited by the distance between, for example, a position detection sensor using the LiDAR system and the object to be measured, thereby reducing variations in signal strength at each measurement point corresponding to the light receiving element of the photodetector and improving measurement accuracy.

[0014] The "LiDAR system" according to the present technology is not limited to a method for measuring an object to be measured, but also includes a device such as a position detection sensor that realizes the measurement. The LiDAR system according to the present technology may be in a form in which the control system is integrally incorporated into a finished product such as a device, or may be in a form in which the control system is detachably incorporated into the finished product like a component to be incorporated into the device.

[0015] In this technology, the "optical axis of the light source" refers to a normal line passing through the center of the light-emitting element on the light-emitting surface, and the "optical axis of the optical element" refers to a normal line passing through the center of the optical element. When the direction of light is changed using a beam splitter or the like, the "optical axis" includes the main axis along which light passing through the optical axis before the change in direction of travel travels after the change in direction of travel. For example, when the direction of light from a light-emitting element in a light source is changed, the "optical axis of the light source" also includes the straight line along which light emitted from the center line of the light-emitting element in the light source passes after being changed by the beam splitter or the like.

[0016] In the present technology, "arranged on the optical axis" refers to a state in which an optical element to be arranged is arranged on the optical axis, and unless otherwise specified, refers to an arrangement in which the center of the optical element is located on the optical axis.

[0017] FIG. 2 is a conceptual diagram of a conventional LiDAR system. The conventional LiDAR system 10b includes a light source 19 and a light-receiving condensing optical element 14, and the virtual object plane 17 represents the object to be measured. The light source 19 has a light-emitting surface composed of multiple light-emitting elements 11, and the photodetector also has a light-detecting surface composed of multiple light-receiving elements 16. If the ratio of the focal lengths of the lens (collimating optical element) 13 on the light source side and the lens (condensing optical element) 14 on the light-receiving side is equal to the ratio of the pitch of the light-emitting elements of the light source 19 to the pitch of the light-receiving elements of the condensing optical element 14, the light emitted from each light-emitting element and scattered on the virtual object plane 17 can be collected by each light-receiving element. However, the ratio of the dimensions of the light-emitting elements to the light-receiving elements is not generally equal to the ratio of the pitch of the light-emitting elements to the light-receiving elements. FIG. 2 shows a schematic diagram of the case where the image size of the light source is smaller than the light detection surface when the ratio of the lens focal lengths is matched to the pitch ratio, i.e., the ratio of the light emitting surface size to the light detection surface size is smaller than the ratio of the light emitting element pitch to the light receiving element pitch.

[0018] In this case, light is received only in a portion of the light receiving element 16, and not in the other portions of the light receiving element 16. If the optical density of the light focused on the light receiving element 16 becomes high, the response speed of the light receiving element 16 will decrease and distortion will occur, resulting in a decrease in sensing sensitivity. Therefore, an optical design that allows light to be received by the entire light receiving element is desirable.

[0019] 2 is scattered on the virtual object plane 17 and collected on multiple light receiving elements 16, some light receiving elements receive light and some light receiving elements do not. Since no signal is detected in the pixels of the light receiving elements that do not receive light, it is assumed that the virtual object 17 does not exist, which causes problems in measurement.

[0020] 1 is a conceptual diagram of a LiDAR system according to the present technology. In addition to the configuration of the LiDAR system of the above-described conventional technology, a LiDAR system 10 according to the present technology includes a reflective amplifying light-guiding element 12 having an incident surface, a light-guiding path, and an output surface, which is located on an optical axis A of a light-emitting element 11 included in a light source 19 and between the light source 19 and a collimating optical element 13.

[0021] Light emitted from the light-emitting element 11 of the light source 19 and incident on the incident surface of the reflective amplifying light-guiding element 12 is reflected multiple times within the light-guiding path of the reflective amplifying light-guiding element 12, resulting in light with a uniformly distributed intensity. The light is then guided along the light-guiding path to the collimating optical element. This allows for a uniform distribution of light, regardless of the distance between the object being measured and a position detection sensor, such as a LiDAR system, and prevents a decrease in sensing sensitivity. Furthermore, in a configuration in which multiple light-receiving surfaces correspond to one light-emitting surface, light is received by all of the light-receiving surfaces, preventing a decrease in the number of pixels being sensed.

[0022] 3 is a schematic diagram of an optical system showing an example of the overall configuration required for a LiDAR system of the present technology. The LiDAR system 10 of the present technology includes, as an essential component, a reflective amplification light-guiding element 12 in addition to the configuration of a conventional LiDAR system including a light source 19, a collimating optical element 13, a focusing optical element 14, and a photodetector 15 having a light detection surface including a light receiving element 16.

[0023] As described above, the LiDAR system 10 of the present technology includes a reflective amplifying light-guiding element 12 in addition to the configuration of a conventional LiDAR system. Light incident on the incident surface of the reflective amplifying light-guiding element 12 is reflected multiple times within the light-guiding path of the reflective amplifying light-guiding element 12, resulting in light with a uniform intensity distribution. This allows the light distribution to be uniform, regardless of the distance between the LiDAR system and the object being measured, preventing a decrease in sensing sensitivity. Furthermore, in a configuration in which multiple light-receiving surfaces correspond to one light-emitting surface, light is received by all light-receiving surfaces, preventing a decrease in the number of sensing pixels.

[0024] The elements that make up the LiDAR system of the present technology will be described in more detail below.

[0025] <Light Source> The light source that can be used in the LiDAR system of the present technology can be any light-emitting element that generates light of a single wavelength or a specific wavelength band suited to the purpose of measurement. For example, as a light source having a two-dimensional light-emitting surface consisting of one or more light-emitting elements, it may be an edge-emitting laser with the end surface as a resonator mirror, or a VCSEL (Vertical Cavity Surface Emitting Laser). In addition, the light source may be operated in pulsed mode or directly modulated. VCSELs are preferable because they do not require a scanning device.

[0026] The number of light-emitting elements included in the light source used in the LiDAR system of the present technology may be one or more, but may also be two or more. For example, the light source may be an array light source having one or more light-emitting elements.

[0027] Furthermore, when a VCSEL is used as a light source that can be used in the LiDAR system of the present technology, for example, a VCSEL array can be constructed by combining VCSEL devices in a two-dimensional arrangement, and can be used as an array light source having multiple light-emitting elements in a compact design.

[0028] Furthermore, in the LiDAR system according to the present technology, the method of irradiating light from the light source to the object to be measured is not particularly limited, and light may be irradiated from any position depending on the characteristics of the object to be measured and the purpose of the measurement. For example, the path of the light can be changed using a beam splitter or the like.

[0029] <Photodetector> The photodetector included in the LiDAR system according to the present technology has one or more photodetectors to detect reflected light from the object to be measured. Here, the term "photodetector" refers to an optical sensor that detects light incident on the photodetector's photodetection surface. Examples of the photodetector include a photomultiplier tube (PMT), a photodiode, a charge-coupled device (CCD), and a complete metal oxide semiconductor (CMOS).

[0030] The light receiving element can convert the detected light into an analog electrical signal by photoelectric conversion, and can further convert the analog electrical signal into a digital electrical signal by AD conversion.

[0031] The number of light receiving elements in the photodetector used in the LiDAR system of the present technology may be one or more, but may also be two or more. Using multiple light receiving elements improves data redundancy and improves measurement accuracy and reliability. Furthermore, as the number of light receiving elements increases, detection at multiple measurement points becomes possible, which may enable multi-directional observation, etc.

[0032] The photodetector used in the LiDAR system of the present technology is disposed on the optical axis of the focusing optical element described below. Note that, if the traveling direction of the reflected light focused by the focusing optical system is changed by a beam splitter or the like as described above, the photodetector is disposed on a straight line along which the reflected light passes after being changed by the beam splitter or the like.

[0033] In addition, by using a light-receiving element array, such as a CCD array or a CMOS image sensor array, as a photodetector that can be used in the LiDAR system of the present technology, the LiDAR system can be designed compactly.

[0034] <Collimating optical element> The collimating optical element provided in the LiDAR system according to the present technology is arranged on the optical axis of the light source provided in the LiDAR system, and can shape the light output from the light source into parallel rays, control the direction of travel of the light in a specific direction, and irradiate the light toward the object to be measured.

[0035] The collimating optical element that can be used in the LiDAR system according to the present technology is not particularly limited as long as it is an optical element that can shape specific light rays or light output from a light source into parallel light rays.

[0036] <Concentrating optical element> The focusing optical element included in the LiDAR system according to the present technology focuses reflected light from an object to be measured that is present in the traveling direction of light from the collimating optical element in the LiDAR system, and guides the light to the photodetector described above.

[0037] The focusing optical element that can be used in the LiDAR system according to the present technology is not particularly limited as long as it is an optical element that can focus light from the object to be measured and form an image.

[0038] <Object to be Measured> As described above, the LiDAR system according to the present technology irradiates light emitted from a light source onto an object to be measured, detects the light reflected from the object to be measured using a light-receiving element of a photodetector, and calculates the distance from the LiDAR system to the object to be measured, the position of the object to be measured, the shape of the object to be measured, etc. based on the time until the detection. Note that if the object to be measured is present in the direction of travel of light emitted from the light source provided in the LiDAR system, the LiDAR system of the present technology can detect the object to be measured. On the other hand, if the object to be measured is not present in the direction of travel of the light, the LiDAR system of the present technology does not detect the object to be measured. In other words, it detects that the object to be measured does not exist.

[0039] The objects to be detected by the LiDAR system of the present technology are not particularly limited, and by adjusting the combination of light sources and photodetectors used depending on the intended use of the LiDAR system, objects of any size can be measured.

[0040] The reflective-amplifying light-guiding element of the LiDAR system according to the present technology is disposed on the optical axis of the light source of the LiDAR system, between the light source and the collimating optical element. The reflective-amplifying light-guiding element has an incident surface onto which light emitted from the light source can be incident, a light guide path that guides the light, and an output surface from which the light that has traveled through the light guide path is output.

[0041] The reflective amplifying light-guiding element adjusts light incident on the incident surface from the light source to light with a uniform intensity distribution by reflecting the light multiple times along the light guide path. The adjusted light is then output from the output surface and guided to a collimating optical element. By including this reflective amplifying light-guiding element, the LiDAR system according to the present technology can uniformize the light distribution regardless of the distance between the LiDAR system and the object to be measured, reducing variation in signal strength at each measurement point corresponding to the light receiving element of the photodetector and improving measurement accuracy.

[0042] (Light guide path) The shape of the light guide path of the reflection-amplifying light guide element included in the LiDAR system according to the present technology is not particularly limited as long as it is a shape that can reflect light incident on the incident surface multiple times along the light guide path. In consideration of increasing the number of times that the incident light is reflected within the light guide path, it is preferable that the length of the longitudinal direction of the light guide path, which is the direction in which the light incident on the incident surface is guided, is longer than the size of the width direction of the incident surface.

[0043] The reflection within the light guide path of light incident on the incident surface of the reflection-amplifying light guide element occurs at the interface (boundary where the refractive index changes) of the region where the material forming the light guide path exists, including the side surface of the light guide path.

[0044] From the viewpoint of efficiently reflecting light incident on the incident surface of the reflective amplifying light-guiding element at the side of the light guide path of the reflective amplifying light-guiding element, it is preferable that the inclination angle formed by the normal to the incident surface and the side of the light guide path of the reflective amplifying light-guiding element provided in the LiDAR system according to the present technology is smaller than the diffraction angle of light incident on the incident surface.

[0045] Here, the diffraction angle of light incident on the incident surface refers to the angle between the normal to the incident surface (corresponding to the direction of travel of the light incident on the incident surface) and the straight line along which the diffracted light travels. Also, the tilt angle formed by the normal to the incident surface and the side surface of the light guide path refers to the angle between the normal to the incident surface and the tangent to the side surface of the light guide path.

[0046] For example, if the light guide has a trumpet-like shape and the shape of the light guide changes along the longitudinal direction of the light guide, the inclination of the tangent to the side surface of the light guide may change depending on the position of the side surface of the light guide. However, in this case as well, from the viewpoint of efficiently reflecting the light incident on the incident surface of the reflective amplifying light guide element by the side surface of the light guide of the reflective amplifying light guide element, it is preferable that the inclination angle formed by the normal to the incident surface and the side surface of the light guide be smaller than the diffraction angle of the light incident on the incident surface over all or a major part of the longitudinal direction of the light guide.

[0047] Furthermore, in the present technology, the "light guide path" of a reflective amplifying light-guiding element refers to a portion where light incident on the incident surface of the reflective amplifying light-guiding element is reflected and allowed to travel in a specific direction. If the side surface of the reflective amplifying light-guiding element is covered with a protective film or the like that does not contribute to the reflection of light incident on the incident surface, the protective film is not included in the light guide path, and the "side surface of the light guide path" refers to the side surface of the portion where light incident on the incident surface of the reflective amplifying light-guiding element is reflected and allowed to travel in a specific direction.

[0048] The shape of the light guide of the reflection-amplifying light guide element included in the LiDAR system according to the present technology may be, for example, a columnar shape such as a cylinder or a polygonal prism, a tapered shape, a curved shape like a trumpet, etc. Two or more of these shapes may also be combined and connected in series in the longitudinal direction of the light guide.

[0049] When the light guide path of the reflection-amplifying light guide element included in the LiDAR system according to the present technology has a columnar shape such as a cylinder or a polygonal prism, the inclination angle formed by the normal to the incident surface and the side surface of the light guide path is 0 degrees. When the light guide path has a tapered shape, the inclination angle formed by the normal to the incident surface and the side surface of the light guide path is greater than 0 degrees, but as described above, this angle is preferably smaller than the diffraction angle of light incident on the incident surface.

[0050] The material forming the light guide path of the reflection-amplifying light guide element included in the LiDAR system according to the present technology is not particularly limited as long as it is a material that can propagate incident light. For example, glass including optical glass such as quartz glass and BK7, and highly transparent resins such as polycarbonate resin (PC), cycloolefin resin (COP), acrylic resin (PMMA), polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polystyrene (PS) can be suitably used. Furthermore, two or more of these materials can also be used in combination.

[0051] The reflective-amplifying light-guiding element included in the LiDAR system according to the present technology may have two or more regions made of materials with different refractive indices. Because the refractive index changes at the interface between the two or more regions made of materials with different refractive indices, light incident in the light guide path is reflected at the interface. Note that, as the materials with different refractive indices, for example, a combination of materials that can form the light guide path of the reflective-amplifying light-guiding element described above can be suitably used, but is not limited thereto.

[0052] In the reflection-amplifying light-guiding element included in the LiDAR system according to the present technology, the interface between two or more regions made of materials with different refractive indices may be set arbitrarily. For example, a laminated structure, a sea-island structure, or a structure in which at least one of the two or more regions forms two or more cylindrical portions along the light-guiding direction may be adopted.

[0053] Here, an example of a structure in which at least one of two or more regions made of materials with different refractive indices forms two or more tubular sections along the light-guiding direction is a structure in which one material is arranged in a fiber-like manner over a certain range inside the other material, such as a bundle fiber.

[0054] From the viewpoint of efficiently increasing the number of reflections per unit length in the longitudinal direction of the light guide and adjusting light with a uniform intensity distribution, it is preferable to increase the area of ​​the interfaces of the two or more regions per unit length in the longitudinal direction of the light guide, because this increases the area of ​​the surface where the refractive index changes (the surface where light is reflected). In this case, it is preferable that the two or more regions are formed continuously over at least a part of the longitudinal range of the light guide along the light guiding direction.

[0055] Here, the above-mentioned "continuously formed along the light guiding direction" is not limited to being continuously formed parallel to the optical axis of the light source, but also includes cases where the angle with respect to the optical axis changes, such as when the light is continuously formed at a constant angle to the optical axis or when the light is continuously formed in a meandering pattern.

[0056] In the reflection-amplifying light-guiding element provided in the LiDAR system according to the present technology, examples of specific structures in which two or more regions made of materials with different refractive indices are formed continuously along the light-guiding direction over at least a portion of the longitudinal direction of the light-guiding path include, for example, a stacked structure and a structure in which at least one of the two or more regions forms two or more cylindrical sections along the light-guiding direction.

[0057] The range in which the two or more regions made of materials with different refractive indices are continuously formed along the light guiding direction may be continuously formed over at least a portion of the longitudinal range of the light guide path, or may be continuously formed over the entire longitudinal range of the light guide path.

[0058] When the reflective amplifying light-guiding element provided in the LiDAR system according to the present technology is made of a laminated structure of materials with different refractive indices, the laminated structure includes a structure in which multiple layers of side walls of approximately the same shape made of one or more materials are stacked from the center of the longitudinal cross section of the light guide path of the reflective amplifying light-guiding element toward the outer edge (side surface of the light guide path), a structure in which layers having laminated surfaces of approximately the same area are stacked in one direction on the laminated surface, and a structure in which layers having laminated surfaces of approximately the same shape are stacked in two or more directions on the laminated surface.

[0059] When the reflection-amplifying light-guiding element has the above-described laminated structure, the cross-sectional shape of the laminated portion may be adjusted appropriately depending on the measurement target expected by the LiDAR system. Furthermore, the number of layers in the laminated structure is not particularly limited, but the greater the number of layers, the more efficiently the number of reflections per unit length in the longitudinal direction of the light guide path can be increased. Based on this, the number of layers in the laminated structure can be suitably selected depending on the measurement target expected by the LiDAR system. Additionally, when the laminated structure is stacked in two or more directions, different numbers of layers may be selected for each stacking direction, or the same number of layers may be selected.

[0060] Furthermore, as described above, the laminated structure may be formed continuously over at least a portion of the longitudinal range of the light guide path of the reflective amplification light guide element provided in the LiDAR system according to the present technology, or may be formed continuously over the entire longitudinal range of the light guide path.

[0061] When the reflection-amplifying light-guiding element included in the LiDAR system according to the present technology has a structure in which at least one of two or more regions made of materials with different refractive indices forms two or more cylindrical portions along the light-guiding direction, an example of the structure is, for example, a bundle fiber structure having two or more cylindrical portions. The two or more cylindrical portions may be formed from a single material or multiple different materials.

[0062] When the reflection-amplifying light-guiding element has the above structure, the cross-sectional shape of the cylindrical portion may be adjusted as appropriate depending on the measurement target intended by the LiDAR system. Furthermore, the number of cylindrical portions formed is not particularly limited, but the more the number of cylindrical portions formed, the more efficiently the number of reflections per unit length in the longitudinal direction of the light guide path can be increased. Based on this, the number of cylindrical portions formed can be suitably selected depending on the measurement target intended by the LiDAR system.

[0063] When the reflective-amplifying light-guiding element has a structure that forms two or more cylindrical portions, the cylindrical portions may be regularly arranged along the light-guiding direction of the light guide path of the reflective-amplifying light-guiding element, or may be randomly arranged. In particular, from the viewpoint of efficiently increasing the number of reflections per unit length in the longitudinal direction of the light guide path, it is preferable that the cylindrical portions be randomly arranged.

[0064] Furthermore, in cases where the reflective amplifying light-guiding element has a structure that forms two or more tubular sections, for example, a tubular section having an end located at the outer edge of the incident surface of the reflective amplifying light-guiding element can be formed so that its end is located at the center on the output surface, while a tubular section having an end located at the center of the incident surface can be formed so that its end is located at the outer edge on the output surface. This increases the interface area per unit length in the longitudinal direction of the light guide path, and efficiently increases the number of reflections per unit length in the longitudinal direction of the light guide path.

[0065] Furthermore, as described above, the structure may be formed continuously over at least a portion of the longitudinal range of the light guide path of the reflective amplification light guide element provided in the LiDAR system according to the present technology, or may be formed continuously over the entire longitudinal range of the light guide path.

[0066] Furthermore, the reflective amplifying light-guiding element provided in the LiDAR system according to the present technology has two or more regions made of materials with different refractive indices, and the inclination angle formed by the normal to the incident surface and the side surface of the light-guiding path is smaller than the diffraction angle of the light incident on the incident surface. This further increases the number of reflections per unit length in the longitudinal direction of the light-guiding path of the reflective amplifying light-guiding element, thereby effectively adjusting the light to have a uniformly distributed intensity.

[0067] The reflective amplification light-guiding element provided in the LiDAR system according to the present technology may be formed by connecting two or more parts along the light-guiding direction, in which the inclination angles formed by the normal to the incident surface and the side surface of the light-guiding path are different from each other.

[0068] In this case, the number of the two or more parts is not particularly limited, and any integer number of two or more parts can be formed by connecting them along the light-guiding direction, depending on the target to be measured by the LiDAR system.

[0069] Furthermore, as described above, in the reflective-amplifying light-guiding element included in the LiDAR system according to the present technology, the inclination angle formed by the normal to the incident surface and the side surface of the light guide path may change along the light guiding direction. However, in this case as well, from the viewpoint of efficiently reflecting light incident on the incident surface of the reflective-amplifying light-guiding element by the side surface of the light guide path of the reflective-amplifying light-guiding element, it is preferable that the inclination angle formed by the normal to the incident surface and the side surface of the light guide path be smaller than the diffraction angle of light incident on the incident surface over the entire or main portion of the longitudinal direction of the light guide path.

[0070] The inclination angle of the reflection-amplifying light-guiding element provided in the LiDAR system according to the present technology can be suitably formed by any method, such as oblique polishing, to achieve the desired inclination angle.

[0071] Furthermore, the reflection-amplifying light-guiding element included in the LiDAR system according to the present technology may include a highly reflective film on the side surface of the light guide path, thereby enabling the light incident on the incident surface to be more effectively reflected by the side surface of the light guide path.

[0072] The highly reflective film on the side of the optical path can be suitably formed using known materials and known methods depending on the intended use of the LiDAR system.

[0073] (Arrangement of Reflective Amplification Light-Guiding Element) The reflective amplification light-guiding element included in the LiDAR system according to the present technology is arranged on the optical axis of the light source, between the light source and the collimating optical element, and it is particularly preferable that the output surface of the reflective amplification light-guiding element is arranged at the focal point of the collimating optical element. This allows the output surface of the reflective amplification light-guiding element to be regarded as a light source (virtual light source), and its image can be transmitted by the collimating optical element. At a sufficiently far distance, the image of the virtual light source can be illuminated onto a virtual subject surface to which it is transmitted.

[0074] In the LiDAR system according to the present technology, the light source and the reflective amplifying light-guiding element are in contact at the incident surface of the reflective amplifying light-guiding element, thereby preventing multiple reflections due to returned light and reducing the number of mounted components.

[0075] The contact between the light source and the reflective amplification light-guiding element is not limited to the case where the two are in contact without being fixed, but also includes the case where the two are in contact while being fixed (adhered).

[0076] In the LiDAR system according to the present technology, when the light source and the reflective amplifying light-guiding element are not in contact at the incident surface of the reflective amplifying light-guiding element, it is preferable that the space between the light source and the incident surface of the reflective amplifying light-guiding element on the optical axis of the light source is filled with one or more adjustment media having the same refractive index.

[0077] The adjustment medium that can be used in the LiDAR system according to the present technology is not particularly limited as long as it has the same refractive index and can fill the space between the light source and the incident surface of the reflective-amplifying light-guiding element, and may be in any state, such as solid, liquid, or gas. Furthermore, it is preferable that the refractive index of the adjustment medium is higher than the refractive index of vacuum and air.

[0078] The LiDAR system according to the present technology may use one type of adjustment medium or a combination of two or more types of adjustment mediums. When two or more types of adjustment mediums are used, materials in multiple states may be combined, such as a solid material and a liquid material.

[0079] In the LiDAR system according to the present technology, when the space between the light source and the incident surface of the reflective amplification light-guiding element is filled with one or more adjustment media having the same refractive index, it is preferable that the refractive index of the adjustment media has a value between the equivalent refractive index of the light source and the refractive index of the material with the lowest refractive index among the materials forming the light-guiding path.

[0080] Here, the material with the lowest refractive index refers to the material with the lowest refractive index among the materials forming the reflective amplifying light-guiding element.

[0081] (Incident surface and output surface) The incident surface of the reflective amplification light-guiding element used in the LiDAR system of the present technology is preferably approximately the same size as or smaller than the light-emitting surface that emits light from the light source, in order to effectively reflect the light incident from the light source within the light-guiding path.

[0082] Here, the expression "substantially the same" for the area of ​​the light-emitting surface that emits light from the light source and the area of ​​the incident surface of the reflective amplifying light-guiding element does not necessarily mean that the areas of the two are completely the same, but also means that the areas are substantially the same to the extent that light incident from the light source along the optical axis direction can be incident.

[0083] Furthermore, the area of ​​the output surface of the reflective-amplifying light-guiding element used in the LiDAR system according to the present technology may be larger than the area of ​​the input surface. As a result, even if the area of ​​the light detection surface of a photodetector consisting of one or more light receiving elements is larger than the area of ​​the light emitting surface of the light source, the area of ​​the light collected by the focusing optical element can be made approximately the same as or larger than the area of ​​the light detection surface of the photodetector. This allows light to be detected by all of the light receiving elements on the light detection surface of the photodetector, and the increased number of light detection points improves the accuracy and reliability of the measurement.

[0084] In this case, the expression "substantially the same" between the area of ​​the light-detecting surface of the light detector and the area of ​​the light-detecting surface of the light-detector does not necessarily mean that the areas of the two are completely the same, but also means that the areas are substantially the same to the extent that substantially all of the reflected light collected by the light-detecting optical element can be received.

[0085] When the area of ​​the output surface of the reflective amplifying light-guiding element is made larger than the area of ​​the incident surface, the shape of the reflective amplifying light-guiding element is not particularly limited, and may be, for example, a shape in which the cross-sectional area changes along the longitudinal direction, such as a tapered shape or a curved shape like a trumpet, or a shape in which a shape with a constant cross-sectional area, such as the aforementioned cylindrical shape or polygonal prism, is combined with a plurality of the above shapes and connected along the direction in which the light guide path guides light.

[0086] The shapes of the incident surface and the output surface of the reflective-amplifying light-guiding element are not particularly limited, and may be, for example, substantially the same as the shape of the light-emitting surface of the light source used in the LiDAR system of the present technology.

[0087] Even when a reflective amplifying light-guiding element in which the area of ​​the output surface is larger than the area of ​​the incident surface is used in the LiDAR system of the present technology, it is preferable that the incident surface of the reflective amplifying light-guiding element be approximately the same size as or smaller than the light-emitting surface that emits light from the light source, in order to effectively reflect the light incident from the light source within the light guide path.

[0088] In the above case, by designing the area of ​​the output surface of the reflective-amplifying light-guiding element so that the area of ​​the light collected by the collecting optical element is approximately the same as the area of ​​the light-detecting surface, light can be detected by all of the light-receiving elements on the light-detecting surface of the photodetector, which increases the number of light-detecting points and can improve the accuracy and reliability of the measurement.

[0089] The incident surface and the output surface of the reflective amplifying light guide element may be coated with an anti-glare (AR) coating, which can reduce unintended reflection of light.

[0090] The manufacturing method of the reflection-amplifying light-guiding element that can be used in the LiDAR system according to the present technology is not particularly limited, and it can be suitably manufactured by a known method.

[0091] <Other Configurations> The LiDAR system according to the present technology may include other configurations in addition to the above-described configurations as needed, as long as the desired physical properties are not significantly impaired.

[0092] [Optical Components and Reflective Collateral Light-Guiding Elements Used in LiDAR Systems] The reflective amplifying light-guiding elements described in this specification can be suitably used as reflective amplifying light-guiding elements used in LiDAR systems of the present technology.

[0093] Furthermore, an optical component (light source side optical component) comprising a light source having a light emitting surface consisting of one or more light emitting elements and the reflective amplification light-guiding element can be suitably used as an optical component for use in the LiDAR system of the present technology.

[0094] [Position Detection Sensor] The LiDAR system of the present technology can be used as a position detection sensor.

[0095] Here, the term "position detection sensor" refers to a sensing device for measuring the presence or absence of an object in the vicinity of an area targeted by the position detection sensor, the position of the object, and the distance to the object. The position detection sensor according to the present technology may be incorporated as an integral part of a finished product such as a device, or may be incorporated separably into the finished product like a component to be incorporated into a device.

[0096] The position detection sensor of this technology can be used in any form depending on the usage situation for any application that measures a target area, such as environmental recognition and obstacle detection for moving bodies such as vehicles, ships, and airplanes, three-dimensional scanning of structures such as buildings, surveying, etc.

[0097] Here, the term "mobile body" refers to an object or device with a mobility function. Examples include automobiles, motorcycles, electric vehicles, hybrid electric vehicles, motorcycles, personal mobility devices, bicycles, and other vehicles, as well as trains, ships, airplanes, robots, drones, construction machinery, and agricultural machinery (tractors). The movement of a mobile body includes both manual driving, in which a person is directly or indirectly involved in driving, and automated driving, in which a person is not involved in driving.

[0098] The position detection sensor of the present technology operates stably without being affected by environmental weather conditions and can measure objects with low visibility. Therefore, for example, if the moving body given as an example above is equipped with the position detection sensor of the present technology, it can effectively recognize the surrounding environment and detect obstacles.

[0099] Specific embodiments of a LiDAR system according to the present technology will be described below with reference to the drawings. Note that the embodiments described below are examples of embodiments of the present technology, and the present technology should not be interpreted as being limited to the contents of these embodiments.

[0100] 4 is a conceptual diagram illustrating an example of a LiDAR system according to a first embodiment. A LiDAR system 10 according to this embodiment includes a light source 19 having a light-emitting surface made up of one or more light-emitting elements 11, a reflective-amplifying light-guiding element 12, and a photodetector 15 having a light-detecting surface made up of one or more light-receiving elements 16. The shape of the reflective-amplifying light-guiding element 12 used in the LiDAR system of this embodiment shown in FIG. 4 is a columnar shape such as a cylinder or polygonal prism, and the cross-sectional area of ​​the light guide path 12-2 does not change along the longitudinal direction and is a constant shape.

[0101] 4, in order to provide a detailed description of the shape of the reflective-amplifying light-guiding element, which is a feature of the present technology, the collimating optical element, the focusing optical element, and the object to be measured are omitted. Note that the collimating optical element and the focusing optical element may be any optical element described in this specification, etc., depending on the measurement target of the LiDAR system, etc.

[0102] In the LiDAR system 10 of this embodiment, light emitted from the light-emitting element 11 of the light source 19 is incident on the incident surface 12-1 of the reflective amplification light-guiding element 12 arranged on the optical axis A of the light-emitting element 11 between the light source 19 and the collimating optical element (the collimating optical element is omitted in Figure 4).

[0103] Here, Fig. 4 shows an example in which the light-emitting element 11 and the reflective-amplifying light-guiding element 12 are arranged in contact with each other at the incident surface 12-1 as a preferred example of arrangement, but this embodiment is not limited to the example of arrangement shown in Fig. 4. Similarly, Fig. 4 shows an example in which the area of ​​the light-emitting surface that emits light from the light-emitting element 11 and the area of ​​the incident surface 12-1 are approximately the same as each other as a preferred example, but the relationship between the area of ​​the light-emitting surface and the area of ​​the incident surface in this embodiment is not limited to the example shown in Fig. 4.

[0104] The light incident on the incident surface 12-1 of the reflective amplifying light-guiding element 12 is reflected multiple times inside the light guide path 12-2 of the reflective amplifying light-guiding element 12, thereby becoming light with a uniform intensity distribution, which is then guided along the light guide path 12-2 and output from the output surface 12-3 toward the collimating optical element. The light then has its traveling direction controlled in a specific direction by the collimating optical element.

[0105] When an object to be measured exists in the direction of travel of the light controlled by the collimating optical element, the focusing optical element included in the LiDAR system focuses the reflected light from the object to be measured and directs the light onto a light detection surface consisting of one or more light receiving elements 16 of the photodetector 15. By calculating the time it takes for the light emitted from the light source to be detected as reflected light by the light receiving element, it is possible to measure the presence or absence of the object to be measured, its position, and the distance to it.

[0106] In particular, the LiDAR system of this embodiment includes the reflective amplification light guide element 12, which adjusts the light to have a uniform intensity distribution by reflecting the light multiple times inside the light guide path 12-2. By using light with a uniform intensity distribution, the variation in signal intensity at each measurement point corresponding to the light receiving element of the photodetector is reduced, thereby improving the measurement accuracy of the LiDAR system of this embodiment.

[0107] The reflective amplification light-guiding element that can be used in the LiDAR system of this embodiment may be suitably subjected to any of the processing described in this specification, and can be suitably manufactured using known methods.

[0108] 4 shows an example in which there are three combinations of a light-emitting element 11, a reflection-amplifying light-guiding element 12, and a light detection surface consisting of one or more light-receiving elements 16, but this number is not limited to three, and any number of combinations can be used depending on the intended measurement target of the LiDAR system. Although not specified in FIG. 4, the light detection surface of the photodetector 15 may be formed from one light-receiving element, or may be formed from multiple light-receiving elements. Also, while FIG. 4 shows an example in which the light-emitting element 11 and the light-receiving elements correspond to each other in a one-to-one ratio, multiple light-receiving elements may be associated with one light-emitting element depending on the intended measurement target of the LiDAR system.

[0109] 2 Second Embodiment Figure 5 is a conceptual diagram illustrating an example of a LiDAR system according to a second embodiment. The LiDAR system 10 according to this embodiment has the same configuration as the first embodiment, except that the reflective-amplifying light-guiding element 12 has two or more regions made of two or more materials with different refractive indices, and the regions have a laminated structure formed continuously over at least a portion of the longitudinal direction of the light guide path 12-2. Note that in Figure 5, the collimating optical element, focusing optical element, object to be measured, and photodetector are omitted in order to provide a detailed description of the shape of the reflective-amplifying light-guiding element 12, which is a feature of the present technology.

[0110] 5A in FIG. 5 is an image diagram of the LiDAR system 10 viewed from the side, while 5B is an image diagram showing a cross section of the light guide path 12-2 of the reflective amplifying light guide element 12.

[0111] As shown in FIG. 5B, the reflective amplifying light-guiding element 12 has a structure in which eight sidewall members are stacked one on top of the other, extending from the center member of the longitudinal cross section of the light guide 12-2 of the reflective amplifying light-guiding element 12 toward the outer edge (the side surface of the light guide 12-2). By stacking materials with different refractive indices, the refractive index changes at the interface between the layers, and light incident on the light guide 12-2 is reflected at the interface. This allows the number of reflections per unit length in the longitudinal direction of the light guide 12-2 to be efficiently increased. This will be explained using FIG. 6.

[0112] 6 is a conceptual diagram illustrating how the reflective-amplifying light-guiding element used in the LiDAR system according to the second embodiment guides light. It can be seen that the laminated structure along the longitudinal direction of the light guide 12-2 forms an interface between materials with different refractive indices, and that the reflection at this interface efficiently increases the number of reflections per unit length along the longitudinal direction of the light guide 12-2.

[0113] The layer structure of the reflection-amplifying light-guiding element used in the LiDAR system of the second embodiment is not limited to the example shown in Fig. 5 and may have any layer structure. An example of a layer structure other than the layer structure shown in Fig. 5 is the example shown in Fig. 7.

[0114] 7A and 7B are conceptual diagrams illustrating an example of a LiDAR system according to a second embodiment. 7A is a conceptual diagram illustrating the LiDAR system 10 as viewed from the side, while 7B is a conceptual diagram illustrating a cross section of the light guide path 12-2 of the reflective-amplifying light-guiding element 12.

[0115] The reflective amplifying light-guiding element 12 used in the LiDAR system according to the embodiment shown in Figure 7 has a structure in which two layers of side walls of approximately the same shape made of two different materials are stacked from the center of the longitudinal cross section of the light guide 12-2 of the reflective amplifying light-guiding element 12 toward the outer edge (the side surface of the light guide 12-2), as shown in Figure 7B. By increasing the number of layers made of materials with different refractive indices, the surface area of ​​the interface within the light guide 12-2 can be increased, efficiently increasing the number of reflections per unit length in the longitudinal direction of the light guide 12-2. Furthermore, the number of layers made of materials with different refractive indices can be further increased depending on the measurement target, etc., of the object to be measured that the LiDAR system is intended to measure.

[0116] The materials of the components forming the laminated structure of the reflective amplification light-guiding element used in the LiDAR system of the second embodiment may all have different refractive indices, but it is also possible to efficiently narrow down the types of materials used by using only the materials of the components that come into contact at the interface as components with different refractive indices.

[0117] In the second embodiment, other configurations can be suitably adopted that are similar to those that can be adopted in the first embodiment.

[0118] 3 Third Embodiment Fig. 8 is a conceptual diagram illustrating an example of a LiDAR system according to a third embodiment. The LiDAR system 10 according to this embodiment has the same configuration as the first embodiment, except that the reflective-amplifying light-guiding element 12 includes two or more regions made of two or more materials with different refractive indices, and at least one of the two or more regions has a structure (a bundle fiber-like structure) that forms two or more cylindrical sections along the light-guiding direction. Note that in Fig. 8, the collimating optical element, the focusing optical element, the object to be measured, and the photodetector are omitted in order to provide a detailed description of the shape of the reflective-amplifying light-guiding element 12, which is a feature of the present technology.

[0119] The reflective-amplifying light-guiding element 12 used in the third embodiment has two or more regions made of two or more materials with different refractive indices, at least one of which forms two or more cylindrical sections along the light-guiding direction, so that the refractive index changes at the interface between the cylindrical sections, and the light incident on the light guide path 12-2 is reflected at the interface. As a result, as in the case of the reflective-amplifying light-guiding element having a stacked structure used in the second embodiment, the number of reflections per unit length in the longitudinal direction of the light guide path 12-2 can be efficiently increased.

[0120] The two or more cylindrical portions of the reflective amplifying light-guiding element 12 used in the third embodiment may be arranged regularly as described above, or may be arranged randomly. In particular, from the viewpoint of efficiently increasing the number of reflections per unit length in the longitudinal direction of the light guide, it is preferable that the cylindrical portions are arranged randomly. As an example of the arrangement of the cylindrical portions, for example, a cylindrical portion having an end located at the outer edge of the incident surface 12-1 of the reflective amplifying light-guiding element 12 is formed so that the end is located at the center on the output surface 12-3, while a cylindrical portion having an end located at the center of the incident surface 12-1 is formed so that the end is located at the outer edge on the output surface 12-3. This increases the interface area per unit length in the longitudinal direction of the light guide, and efficiently increases the number of reflections per unit length in the longitudinal direction of the light guide.

[0121] The materials of the cylindrical portions and other components that form the reflection-amplifying light-guiding element used in the LiDAR system according to the third embodiment may all be materials with different refractive indices, or only the materials of the components that contact at the interface may be made of materials with different refractive indices, thereby efficiently narrowing down the types of materials used. Furthermore, the cross-sectional shape of the cylindrical portions may be adjusted appropriately depending on the target to be measured by the LiDAR system, and the number of cylindrical portions to be formed may be suitably selected.

[0122] In the third embodiment, other configurations can be suitably adopted that are similar to the configurations that can be adopted in the first or second embodiment.

[0123] 4 Fourth Embodiment Fig. 9 is a conceptual diagram illustrating an example of a LiDAR system according to a fourth embodiment. The LiDAR system 10 according to this embodiment has the same configuration as the first embodiment, except that the area of ​​the output surface 12-3 of the reflective-amplifying light-guiding element 12 is larger than the area of ​​the incident surface 12-1. Note that in Fig. 9, the collimating optical element, the focusing optical element, and the object to be measured are omitted in order to provide a detailed description of the shape of the reflective-amplifying light-guiding element 12, which is a feature of the present technology.

[0124] The reflection-amplifying light-guiding element 12 used in this embodiment has an output surface 12-3 with an area larger than the incident surface 12-1, so that, for example, even if the area of ​​the light-receiving elements 16 of the photodetector 15 is larger than the area of ​​the light-emitting surface of the light-emitting element 11 of the light source 19, the area over which the reflected light is collected by the light-collecting optical element can be efficiently adjusted to be approximately the same as or larger than the area of ​​the light-receiving elements of the photodetector. This allows light to be detected by all of the light-receiving elements 16 on the light-detecting surface of the photodetector 15, and the increased number of light-detecting points improves the accuracy and reliability of the measurement.

[0125] The shape of the reflective amplifying light-guiding element 12 used in this embodiment is an example of a tapered shape in which the cross-sectional area changes along the longitudinal direction. In this case, the inclination angle formed by the side of the tapered light guide 12-2 and the normal to the incident surface 12-1 is greater than 0 degrees, but by making it smaller than the diffraction angle of the light incident on the incident surface, the light incident on the incident surface of the reflective amplifying light-guiding element can be efficiently reflected by the side of the light guide of the reflective amplifying light-guiding element. This will be explained using FIG. 10.

[0126] FIG. 10 is an image diagram showing the light guide in the light guide path taking into account the relationship between the diffraction angle (hereinafter referred to as the “diffraction angle”) of light incident on the incident surface of the reflective amplifying light guide element of the present technology and the inclination angle (hereinafter referred to as the “inclination angle”) formed between the normal X of the incident surface and the side surface of the light guide path.

[0127] 10A shows the diffraction angle α and the light propagation behavior when light emitted from a light source enters the light guide path. 10B shows the light propagation behavior inside the light guide path 12-2 when the tilt angle β is smaller than the diffraction angle α. 10C shows the light propagation behavior inside the light guide path 12-2 when the tilt angle β is smaller than the diffraction angle α.

[0128] When the tilt angle β is smaller than the diffraction angle α, as shown in 10B, the diffracted light can be reflected by the side surface of the light guide 12-2, and it can be confirmed that the diffracted light can be efficiently reflected by the side surface. Therefore, the diffracted light can be effectively guided. On the other hand, when the tilt angle β is smaller than the diffraction angle α, as shown in 10C, the diffracted light cannot be reflected by the side surface of the light guide 12-2. As a result, the diffracted light cannot be effectively guided.

[0129] Next, using Figure 11, we will explain the effect of efficiently adjusting the range of light focused by the focusing optical element to match the area of ​​the light detection surface of the photodetector by using a reflective amplification light-guiding element to adjust the area of ​​the output surface relative to the area of ​​the incident surface when the area of ​​the light-receiving element 16 of the photodetector 15 is larger than the area of ​​the light-emitting surface of the light-emitting element 11 of the light source 19.

[0130] Figure 11 is an image diagram showing the relationship between the range of light reflected by the focusing optical element provided in the LiDAR system and the area of ​​the light detection surface of the photodetector.

[0131] 11A shows the relationship between the area of ​​the light detection surface of the photodetector and the area of ​​the light collection area of ​​the light collection optical element reflected by the light collection optical element when the cross-sectional area of ​​the light guide path of the reflective amplification light guide element is not changed along the longitudinal direction and the areas of the incident and output surfaces are not changed in the LiDAR system of the present technology. 11B shows the relationship between the area of ​​the light collection area of ​​the light collection optical element reflected by the light collection optical element and the area of ​​the light detection surface of the photodetector when the area of ​​the output surface of the reflective amplification light guide element is made larger than the area of ​​the incident surface. Note that in both cases, the relationship between the area of ​​the light collection area of ​​the light collection optical element reflected by the light collection optical element and the area of ​​the light detection surface of the photodetector is shown when the area of ​​the light detection surface of the photodetector is larger than the area of ​​the light emission surface of the light source.

[0132] If the cross-sectional area of ​​the light guide path of the reflective-amplifying light guide element is not changed along the longitudinal direction and the areas of the incident and output surfaces are not changed, then as shown in 11A, the area L of the light collected by the light collecting optical element will be smaller than the area of ​​the light receiving element 16. As a result, if there are multiple light receiving elements 16 on the light detection surface, it will not be possible to detect light using all of the light receiving elements.

[0133] On the other hand, when the area of ​​the output surface of the reflective-amplifying light-guiding element is made larger than the area of ​​the incident surface, as shown in 11B, it is possible to adjust the range L of the light collected by the collecting optical element to be approximately equal to the area of ​​the light-receiving element 16. As a result, when there are multiple light-receiving elements 16 on the light detection surface, light can be detected by all of the light-receiving elements.

[0134] In the example of the fourth embodiment shown in Figure 9, a tapered shape is shown as an example of the shape of the reflective amplifying light-guiding element that makes the area of ​​the output surface of the reflective amplifying light-guiding element larger than the area of ​​the incident surface, but this shape is not limited to this, and any shape can be adopted depending on the relationship between the area of ​​the light-emitting surface of the light source and the area of ​​the light-detecting surface of the photodetector, the target to be measured by the LiDAR system, etc.

[0135] In the fourth embodiment, other configurations can be suitably adopted that are similar to the configurations that can be adopted in the first to third embodiments.

[0136] 5. Fifth Embodiment FIG. 12 is a conceptual diagram illustrating an example of a LiDAR system according to a fifth embodiment, and FIG. 13 is a conceptual diagram illustrating a modified example thereof. The LiDAR system 10 according to this embodiment has the same configuration as the first embodiment, except that the reflective-amplifying light-guiding element 12 is formed by connecting two or more sections in which the normal to the incident surface 12-1 and the side surface of the light-guiding path 12-2 form different inclination angles along the light-guiding direction of the light guide path 12-2. Note that in FIGS. 12 and 13, the collimating optical element, the focusing optical element, the object to be measured, and the photodetector are omitted in order to provide a detailed description of the shape of the reflective-amplifying light-guiding element 12, which is a feature of the present technology.

[0137] Specifically, the reflective amplifying light-guiding element 12 provided in the LiDAR system according to the fifth embodiment shown in Figures 12 and 13 is formed by connecting the reflective amplifying light-guiding element of the first embodiment and the reflective amplifying light-guiding element of the fourth embodiment along the direction in which the light guide path guides light.

[0138] 12 shows a reflective amplifying light-guiding element 12 according to the fifth embodiment, in which a portion having the shape of the fourth embodiment, in which the cross-sectional area varies along the longitudinal direction, is disposed on a side of the light guide 12-2 closer to the light source 19, and a portion having the shape of the first embodiment, in which the cross-sectional area does not vary along the longitudinal direction, is disposed on a side away from the light source 19, and these two portions are connected together. On the other hand, a reflective amplifying light-guiding element 12 according to a modified example of the fifth embodiment, in which a portion having the shape of the first embodiment, in which the cross-sectional area does not vary along the longitudinal direction, is disposed on a side of the light guide 12-2 closer to the light source 19, and a portion having the shape of the fourth embodiment, in which the cross-sectional area varies along the longitudinal direction, is disposed on a side away from the light source 19, and these two portions are connected together.

[0139] The examples shown in Figures 12 and 13 show an example in which a reflective amplification light-guiding element is used, which is formed by connecting two parts with different inclination angles formed by the normal to the incident surface 12-1 and the side surface of the light-guiding path 12-2 along the direction in which the light is guided by the light-guiding path 12-2.However, depending on the target to be measured by the LiDAR system, or in accordance with the relationship between the area of ​​the light-emitting surface of the light source and the area of ​​the light-detecting surface of the photodetector, a reflective amplification light-guiding element formed by connecting three or more parts with any inclination angle can also be used.

[0140] In the fifth embodiment, other configurations can be suitably adopted that are similar to the configurations that can be adopted in the first to fourth embodiments.

[0141] 6 Sixth Embodiment FIG. 14 is an image diagram illustrating an example of a LiDAR system according to a sixth embodiment, and FIGS. 15 and 16 are image diagrams illustrating modifications thereof. In the LiDAR system 10 according to this embodiment, the reflective-amplifying light-guiding element 12 has the shape of the fourth embodiment, in which the cross-sectional area varies along the longitudinal direction, and the feature of the second embodiment, in which the reflective-amplifying light-guiding element 12 has two or more regions made of two or more materials with different refractive indices, and the regions are a laminated structure formed continuously over at least a portion of the longitudinal direction of the light guide 12-2, or the feature of the third embodiment, in which the reflective-amplifying light-guiding element 12 has two or more regions made of two or more materials with different refractive indices, and at least one of the two or more regions has a structure (a bundle fiber-like structure) forming two or more cylindrical sections along the light-guiding direction. The other configurations are similar to those of the first embodiment. Note that in FIGS. 14 and 15, the collimating optical element, focusing optical element, object to be measured, and photodetector are omitted in order to provide a detailed description of the shape of the reflective-amplifying light-guiding element 12, which is a feature of the present technology. Similarly, in FIG. 16, the collimating optical element, the focusing optical element, and the object to be measured are omitted.

[0142] 14A in Fig. 14 is an image diagram of LiDAR system 10 viewed from the side, while 14B is an image diagram showing a cross section of light guide path 12-2 of reflective amplifying light-guiding element 12. Similarly, 15A in Fig. 15 is an image diagram of LiDAR system 10 viewed from the side, while 15B is an image diagram showing a cross section of light guide path 12-2 of reflective amplifying light-guiding element 12.

[0143] The reflective amplifying light-guiding element 12 used in the LiDAR system shown in Figure 14 has a structure in which the cross-sectional area of ​​the light guide 12-2 changes along the longitudinal direction, and a layer of sidewall members made of eight members is stacked from the center member of the longitudinal cross section of the light guide 12-2 of the reflective amplifying light-guiding element 12 toward the outer edge (side surface of the light guide 12-2). Also, the reflective amplifying light-guiding element 12 used in the LiDAR system shown in Figure 15 has a structure in which the cross-sectional area of ​​the light guide 12-2 changes along the longitudinal direction, and two layers of sidewalls of approximately the same shape made of two types of members are stacked from the center member of the longitudinal cross section of the light guide 12-2 of the reflective amplifying light-guiding element 12 toward the outer edge (side surface of the light guide 12-2).

[0144] The reflection-amplifying light-guiding element of this embodiment has the shape of the fourth embodiment and the features of the second or third embodiment, so even if the area of ​​the light-receiving element 16 of the photodetector 15 is larger than the area of ​​the light-emitting surface of the light-emitting element 11 of the light source 19, the range of light focused by the focusing optical element and the area of ​​the light-detecting surface can be adjusted to be approximately the same, and by adjusting the number of layers made of materials with different refractive indices stacked, the surface area of ​​the interface within the light guide path can be increased, and the number of reflections per unit length in the longitudinal direction of the light guide path can be efficiently increased.

[0145] Furthermore, the tilt angle may be adjusted as desired depending on the intended measurement target of the LiDAR system or the relationship between the area of ​​the light-emitting surface of the light source and the area of ​​the light-detecting surface of the photodetector, and the number of stacked layers made of materials with different refractive indices may be adjusted. In this case, the reflective-amplifying light-guiding element can be used under a suitable combination of conditions similar to those that can be used for the reflective-amplifying light-guiding elements of the second and fourth embodiments.

[0146] The reflective amplification light guide element 12 used in the LiDAR system shown in Figure 16 has a structure in which the cross-sectional area of ​​the light guide path 12-2 changes along the longitudinal direction, and at least one of two or more regions made of two or more materials with different refractive indices forms two or more cylindrical sections along the light guide direction.

[0147] 14 and 15, the reflective-amplifying light-guiding element according to this embodiment shown in Fig. 16 also has the shape of the fourth embodiment and the features of the third embodiment, so that even if the area of ​​the light-receiving element 16 of the photodetector 15 is larger than the area of ​​the light-emitting surface of the light-emitting element 11 of the light source 19, the area where the reflected light is collected by the collecting optical element and the area of ​​the light-detecting surface can be adjusted to be approximately the same, and the surface area of ​​the interface within the light guide can be increased, thereby efficiently increasing the number of reflections per unit length in the longitudinal direction of the light guide. Even in this case, the reflective-amplifying light-guiding element can be used by suitably combining conditions similar to those that can be used for the reflective-amplifying light-guiding elements of the third and fourth embodiments.

[0148] In the sixth embodiment, other configurations can be suitably adopted that are similar to the configurations that can be adopted in the first to fifth embodiments.

[0149] 7 Seventh Embodiment Fig. 17 is an image diagram showing an example of a LiDAR system according to a seventh embodiment, and Fig. 18 is an image diagram showing a modified example thereof. In the LiDAR system 10 according to this embodiment, the reflective-amplifying light-guiding element 12 is formed by connecting two or more different parts having the features or shapes, such as the inclination angle, of the first to sixth embodiments along the light-guiding direction of the light guide path 12-2. It should be noted that Figs. 17 and 18 omit the collimating optical element, the focusing optical element, the object to be measured, and the photodetector in order to provide a detailed description of the shape of the reflective-amplifying light-guiding element 12, which is a feature of the present technology.

[0150] The reflective amplification light-guiding element provided in the LiDAR system of this embodiment is designed by combining the features or shapes such as the inclination angle of the first to sixth embodiments according to the target to be measured by the LiDAR system, or according to the relationship between the area of ​​the light-emitting surface of the light source and the area of ​​the light-detecting surface of the photodetector.

[0151] Specifically, the reflective amplification light guide element 12 used in the LiDAR system shown in Figure 17 is formed by arranging a portion having the shape of the fourth embodiment and the features of the third embodiment on the side of the light guide path 12-2 closer to the light source 19, and arranging a portion having the shape of the first embodiment whose cross-sectional area does not change along the longitudinal direction on the side away from the light source 19, and connecting the two.

[0152] Furthermore, the reflection-amplifying light-guiding element 12 used in the LiDAR system shown in Figure 18 is formed by arranging a first portion having the shape of the fourth embodiment and the features of the third embodiment on the side of the light guide 12-2 closer to the light source 19, along the direction in which the light is guided by the light guide 12-2, next to which is arranged a second portion having the shape of the first embodiment, whose cross-sectional area does not change along the longitudinal direction, next to which is arranged a third portion having the features of the third embodiment, and next to which is arranged a second portion having the shape of the first embodiment, whose cross-sectional area does not change along the longitudinal direction, and these portions are connected together.

[0153] Fig. 19 is an image diagram showing how the reflective-amplifying light-guiding element shown in Fig. 17 guides light. Light emitted from a light source along the longitudinal direction of light guide path 12-2 enters incident surface 12-1, and in a section disposed closer to the light source and having the shape of the fourth embodiment and the features of the third embodiment, the light is repeatedly reflected at the interface between materials with different refractive indices, and then further reflected multiple times within a section disposed adjacent thereto and having the shape of the first embodiment, thereby adjusting the light to have a uniformly distributed intensity, and outputting it from output surface 12-3 toward the collimating optical element.

[0154] The reflective-amplifying light-guiding element used in the LiDAR system according to this embodiment can be formed by connecting two or more different parts having the features or shapes such as inclination angles according to the first to sixth embodiments, depending on the target to be measured that the LiDAR system is intended to measure, or in accordance with the relationship between the area of ​​the light-emitting surface of the light source and the area of ​​the light-detecting surface of the photodetector. In this case, the reflective-amplifying light-guiding element can be used in a suitable combination of conditions similar to those that can be used for the reflective-amplifying light-guiding elements according to the first to sixth embodiments.

[0155] In the seventh embodiment, other configurations can be suitably adopted that are similar to the configurations that can be adopted in the first to sixth embodiments.

[0156] <Embodiment Relating to Position Detection Sensor> FIG. 20 is an image diagram showing an example of an embodiment of a position detection sensor including a LiDAR system of the present technology.

[0157] In a position detection sensor 20 equipped with a LiDAR system according to the present technology, light emitted from a light source included in an optical component 18 (light source-side optical component) used in the LiDAR system according to the present technology includes a light source having a light-emitting surface composed of one or more light-emitting elements and a reflection-amplifying light-guiding element, and the reflection-amplifying light-guiding element adjusts the light to have a uniform intensity distribution, and the light is made incident on a collimating optical element 13 arranged on the optical axis of the light source. The light travels along a path adjusted by the collimating optical element 13, and if an object to be measured 17 is present on the path, the light is irradiated onto the object to be measured 17.

[0158] Thereafter, the light irradiated onto the object 17 to be measured is incident on the focusing optical element 14 as reflected light from the object 17, and the focusing optical element 14 focuses the reflected light onto the light detection surface of the photodetector 15, which has a light detection surface made up of one or more light receiving elements. As a result, by calculating the time it takes for the light emitted from the light source to be reflected from the object 17 to be detected by the light receiving elements on the light detection surface of the photodetector 15, it is possible to calculate the distance to the object 17 to be measured and the position of the object 17. Note that if the object 17 to be measured is not present in the traveling direction of the light from the collimating optical element 13, no reflected light is generated.

[0159] FIG. 21 is an image diagram of the vicinity of the light source in a position detection sensor 20 equipped with a LiDAR system according to the present technology, in which the output surface of the reflective amplification light-guiding element is placed at the focus of the collimating optical element.

[0160] In the position detection sensor equipped with the LiDAR system of the present technology, the reflective amplification light-guiding element 12 is disposed on the optical axis of the light-emitting element 11, between the light-emitting element 11 and the collimating optical element 13. In particular, by disposing the output surface of the reflective amplification light-guiding element 12 at the focal point of the collimating optical element 13, diffracted light generated when light is output from the output surface of the reflective amplification light-guiding element 12 can be suitably output to the collimating optical element, and the LiDAR system can be configured compactly. As a result, the collimating optical element can convert the light output from the output surface into parallel rays and suitably irradiate the light toward the object to be measured.

[0161] Fig. 22 is an image diagram of the light emitting surface ([22A]) of the light source 19 and the light detecting surface ([22B]) of the photodetector 15 in a position detection sensor 20 equipped with the LiDAR system of the present technology. Here, the light detecting surface may be made up of a single light receiving element, or may be made up of multiple light receiving elements 16. Note that Fig. 22 shows an example in which the area of ​​the light receiving element of the photodetector 15 is larger than the area of ​​the light emitting surface of the light emitting element 11, but this is not intended to be limiting.

[0162] In the position detection sensor of the present technology, the LiDAR system of the present technology, which is equipped with a reflective amplification light-guiding element, can use light that has been adjusted to have a uniformly distributed intensity.This means that the position detection sensor, etc., is not limited by the distance between the position detection sensor, etc. and the object to be measured, and the variation in signal strength at each measurement point corresponding to the light-receiving element of the photodetector 15 is reduced, thereby improving measurement accuracy.

[0163] Furthermore, the area of ​​the output surface of the reflective amplification light-guiding element used in the position detection sensor of the present technology may be larger than the area of ​​the incident surface. This allows the area of ​​the light collected by the collecting optical element and the area of ​​the light detection surface to be adjusted to be approximately the same. As a result, even if there are multiple light receiving elements on the light detection surface, light can be detected by all of the light receiving elements.

[0164] In the position detection sensor of the present technology, a reflection-amplifying light-guiding element that can be used in the LiDAR system of the present technology, such as the reflection-amplifying light-guiding elements of the first to seventh embodiments, can be suitably used. Furthermore, other configurations of the LiDAR system can be suitably adopted as described in this specification. Furthermore, the position detection sensor according to the present technology can also be provided with any other configuration as needed, as long as the desired physical properties are not significantly impaired.

[0165] The technology according to the present disclosure 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, a robot, a construction machine, or an agricultural machine (tractor).

[0166] 23 is a block diagram showing a schematic configuration example of a vehicle control system 7000, which is an example of a mobile object control system to which the technology according to the present disclosure can be applied. The vehicle control system 7000 includes a plurality of electronic control units connected via a communication network 7010. In the example shown in FIG. 23 , the vehicle control system 7000 includes a drive system control unit 7100, a body system control unit 7200, a battery control unit 7300, an outside-vehicle information detection unit 7400, an inside-vehicle information detection unit 7500, and an integrated control unit 7600. The communication network 7010 connecting these multiple control units may be an in-vehicle communication network conforming to any standard, such as a control area network (CAN), a local interconnect network (LIN), a local area network (LAN), or FlexRay (registered trademark).

[0167] Each control unit includes a microcomputer that performs arithmetic processing according to various programs, a memory unit that stores the programs executed by the microcomputer or parameters used in various calculations, and a drive circuit that drives various controlled devices. Each control unit includes a network I / F for communicating with other control units via a communication network 7010, and a communication I / F for communicating with devices or sensors inside and outside the vehicle via wired or wireless communication. Figure 23 illustrates the functional configuration of the integrated control unit 7600, including a microcomputer 7610, a general-purpose communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiving unit 7650, an in-vehicle device I / F 7660, an audio / video output unit 7670, an in-vehicle network I / F 7680, and a memory unit 7690. The other control units also include a microcomputer, a communication I / F, a memory unit, and the like.

[0168] The drivetrain control unit 7100 controls the operation of devices related to the drivetrain of the vehicle in accordance with various programs. For example, the drivetrain control unit 7100 functions as a control device for a drive force generating device for generating drive force for the vehicle, such as an internal combustion engine or a drive motor, a drive force transmission mechanism for transmitting drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating braking force for the vehicle. The drivetrain control unit 7100 may also function as a control device for an ABS (Antilock Brake System) or an ESC (Electronic Stability Control), etc.

[0169] A vehicle state detection unit 7110 is connected to the drivetrain control unit 7100. The vehicle state detection unit 7110 includes at least one of a gyro sensor that detects the angular velocity of the axial rotational motion of the vehicle body, an acceleration sensor that detects the acceleration of the vehicle, or a sensor that detects the amount of operation of the accelerator pedal, the amount of operation of the brake pedal, the steering angle of the steering wheel, the engine rotation speed, the rotation speed of the wheels, etc. The drivetrain control unit 7100 performs arithmetic processing using signals input from the vehicle state detection unit 7110, and controls the internal combustion engine, the drive motor, the electric power steering device, the brake device, etc.

[0170] The body system control unit 7200 controls the operation of various devices equipped in the vehicle body according to various programs. For example, the body system control unit 7200 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 7200. The body system control unit 7200 receives these radio waves or signals and controls the vehicle's door lock device, power window device, lamps, etc.

[0171] The battery control unit 7300 controls the secondary battery 7310, which is the power supply source for the drive motor, in accordance with various programs. For example, information such as battery temperature, battery output voltage, or remaining battery capacity is input to the battery control unit 7300 from a battery device equipped with the secondary battery 7310. The battery control unit 7300 performs arithmetic processing using these signals, and controls the temperature regulation of the secondary battery 7310 or a cooling device or the like equipped in the battery device.

[0172] The outside vehicle information detection unit 7400 detects information outside the vehicle equipped with the vehicle control system 7000. For example, at least one of an imaging unit 7410 and an outside vehicle information detection unit 7420 is connected to the outside vehicle information detection unit 7400. The imaging unit 7410 includes at least one of a time-of-flight (ToF) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. The outside vehicle information detection unit 7420 includes at least one of an environmental sensor for detecting the current weather or climate, or a surrounding information detection sensor for detecting other vehicles, obstacles, pedestrians, etc. around the vehicle equipped with the vehicle control system 7000.

[0173] The environmental sensor may be, for example, at least one of a raindrop sensor that detects rain, a fog sensor that detects fog, a sunshine sensor that detects the degree of sunshine, and a snow sensor that detects snowfall. The surrounding information detection sensor may be at least one of an ultrasonic sensor, a radar device, and a LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) device. The imaging unit 7410 and the outside vehicle information detection unit 7420 may each be provided as an independent sensor or device, or may be provided as a device in which multiple sensors or devices are integrated.

[0174] 24 shows an example of the installation positions of the imaging unit 7410 and the vehicle exterior information detection unit 7420. The imaging units 7910, 7912, 7914, 7916, and 7918 are provided, for example, at least one of the front nose, side mirrors, rear bumper, back door, and upper part of the windshield inside the vehicle cabin of the vehicle 7900. The imaging unit 7910 provided on the front nose and the imaging unit 7918 provided on the upper part of the windshield inside the vehicle cabin mainly acquire images of the front of the vehicle 7900. The imaging units 7912 and 7914 provided on the side mirrors mainly acquire images of the sides of the vehicle 7900. The imaging unit 7916 provided on the rear bumper or back door mainly acquires images of the rear of the vehicle 7900. The imaging unit 7918 provided on the upper part of the windshield inside the vehicle cabin is mainly used to detect leading vehicles, pedestrians, obstacles, traffic lights, traffic signs, lanes, etc.

[0175] 24 shows an example of the imaging ranges of the imaging units 7910, 7912, 7914, and 7916. Imaging range a indicates the imaging range of the imaging unit 7910 provided on the front nose, imaging ranges b and c indicate the imaging ranges of the imaging units 7912 and 7914 provided on the side mirrors, respectively, and imaging range d indicates the imaging range of the imaging unit 7916 provided on the rear bumper or back door. For example, by overlaying the image data captured by the imaging units 7910, 7912, 7914, and 7916, a bird's-eye view image of the vehicle 7900 viewed from above can be obtained.

[0176] The outside vehicle information detection units 7920, 7922, 7924, 7926, 7928, and 7930 provided on the front, rear, sides, corners, and above the windshield inside the vehicle cabin of the vehicle 7900 may be, for example, ultrasonic sensors or radar devices. The outside vehicle information detection units 7920, 7926, and 7930 provided on the front nose, rear bumper, back door, and above the windshield inside the vehicle cabin of the vehicle 7900 may be, for example, LIDAR devices. These outside vehicle information detection units 7920 to 7930 are mainly used to detect preceding vehicles, pedestrians, obstacles, etc.

[0177] Returning to FIG. 23 , the explanation will be continued. The outside vehicle information detection unit 7400 causes the imaging unit 7410 to capture an image outside the vehicle and receives the captured image data. The outside vehicle information detection unit 7400 also receives detection information from the connected outside vehicle information detection unit 7420. If the outside vehicle information detection unit 7420 is an ultrasonic sensor, a radar device, or a LIDAR device, the outside vehicle information detection unit 7400 emits ultrasonic waves or electromagnetic waves and receives information on the received reflected waves. Based on the received information, the outside vehicle information detection unit 7400 may perform object detection processing or distance detection processing for people, vehicles, obstacles, signs, text on the road, etc. Based on the received information, the outside vehicle information detection unit 7400 may also perform environment recognition processing for recognizing rainfall, fog, road conditions, etc. Based on the received information, the outside vehicle information detection unit 7400 may also calculate the distance to an object outside the vehicle.

[0178] The outside vehicle information detection unit 7400 may also perform image recognition processing or distance detection processing to recognize people, vehicles, obstacles, signs, or characters on the road surface based on the received image data. The outside vehicle information detection unit 7400 may perform processing such as distortion correction or alignment on the received image data, and may also generate an overhead image or a panoramic image by combining image data captured by different image capturing units 7410. The outside vehicle information detection unit 7400 may also perform viewpoint conversion processing using image data captured by different image capturing units 7410.

[0179] The interior information detection unit 7500 detects information inside the vehicle. A driver state detection unit 7510 that detects the driver's state is connected to the interior information detection unit 7500, for example. The driver state detection unit 7510 may include a camera that captures an image of the driver, a biosensor that detects the driver's biometric information, or a microphone that collects sound from within the vehicle cabin. The biosensor is provided, for example, on the seat or steering wheel, and detects the biometric information of a passenger sitting in the seat or the driver gripping the steering wheel. The interior information detection unit 7500 may calculate the driver's level of fatigue or concentration based on the detection information input from the driver state detection unit 7510, or may determine whether the driver is dozing off. The interior information detection unit 7500 may perform processing such as noise canceling on the collected audio signal.

[0180] The integrated control unit 7600 controls the overall operation of the vehicle control system 7000 according to various programs. An input unit 7800 is connected to the integrated control unit 7600. The input unit 7800 may be implemented by a device that can be operated by a passenger, such as a touch panel, a button, a microphone, a switch, or a lever. Data obtained by voice recognition of a voice input through a microphone may be input to the integrated control unit 7600. The input unit 7800 may be, for example, a remote control device using infrared or other radio waves, or an externally connected device such as a mobile phone or a personal digital assistant (PDA) that can operate the vehicle control system 7000. The input unit 7800 may be, for example, a camera, in which case the passenger can input information using gestures. Alternatively, data obtained by detecting the movement of a wearable device worn by the passenger may be input. Furthermore, the input unit 7800 may include, for example, an input control circuit that generates an input signal based on information input by the passenger using the input unit 7800 and outputs the input signal to the integrated control unit 7600. Passengers and the like operate this input unit 7800 to input various data to the vehicle control system 7000 and to instruct processing operations.

[0181] The storage unit 7690 may include a ROM (Read Only Memory) that stores various programs executed by the microcomputer, and a RAM (Random Access Memory) that stores various parameters, calculation results, sensor values, etc. The storage unit 7690 may also be realized by a magnetic storage device such as an HDD (Hard Disc Drive), a semiconductor storage device, an optical storage device, a magneto-optical storage device, or the like.

[0182] The general-purpose communication I / F 7620 is a general-purpose communication I / F that mediates communication between various devices present in the external environment 7750. The general-purpose communication I / F 7620 may implement a cellular communication protocol such as GSM (Global System of Mobile communications), WiMAX, LTE (Long Term Evolution), or LTE-Advanced (LTE-A), or other wireless communication protocols such as a wireless LAN (also referred to as Wi-Fi (registered trademark)) or Bluetooth (registered trademark). The general-purpose communication I / F 7620 may connect to a device (e.g., an application server or a control server) present on an external network (e.g., the Internet, a cloud network, or an operator-specific network) via, for example, a base station or an access point. The general-purpose communication I / F 7620 may also connect to a terminal present in the vicinity of the vehicle (e.g., a terminal of a driver, a pedestrian, or a store, or an MTC (Machine Type Communication) terminal) using, for example, P2P (Peer to Peer) technology.

[0183] The dedicated communication I / F 7630 is a communication I / F that supports a communication protocol designed for use in vehicles. The dedicated communication I / F 7630 may implement a standard protocol such as WAVE (Wireless Access in Vehicle Environment), which is a combination of a lower layer IEEE 802.11p and an upper layer IEEE 1609, DSRC (Dedicated Short Range Communications), or a cellular communication protocol. The dedicated communication I / F 7630 typically performs V2X communication, which is a concept including one or more of vehicle-to-vehicle communication, vehicle-to-infrastructure communication, vehicle-to-home communication, and vehicle-to-pedestrian communication.

[0184] The positioning unit 7640 performs positioning by receiving, for example, GNSS signals from GNSS (Global Navigation Satellite System) satellites (for example, GPS signals from GPS (Global Positioning System) satellites), and generates position information including the latitude, longitude, and altitude of the vehicle. Note that the positioning unit 7640 may identify the current position by exchanging signals with a wireless access point, or may obtain position information from a terminal such as a mobile phone, PHS, or smartphone that has a positioning function.

[0185] The beacon receiving unit 7650 receives, for example, radio waves or electromagnetic waves transmitted from radio stations or the like installed on the road, and acquires information such as the current location, congestion, road closures, required travel time, etc. The function of the beacon receiving unit 7650 may be included in the dedicated communication I / F 7630 described above.

[0186] The in-vehicle device I / F 7660 is a communication interface that mediates connections between the microcomputer 7610 and various in-vehicle devices 7760 present in the vehicle. The in-vehicle device I / F 7660 may establish a wireless connection using a wireless communication protocol such as a wireless LAN, Bluetooth (registered trademark), NFC (Near Field Communication), or WUSB (Wireless USB). The in-vehicle device I / F 7660 may also establish a wired connection via a connection terminal (and, if necessary, a cable) not shown, such as a Universal Serial Bus (USB), a High-Definition Multimedia Interface (HDMI (registered trademark), or an MHL (Mobile High-Definition Link)). The in-vehicle device 7760 may include, for example, at least one of a mobile device or wearable device owned by a passenger, or an information device carried or installed in the vehicle. The in-vehicle device 7760 may also include a navigation device that searches for a route to a desired destination. The in-vehicle device I / F 7660 exchanges control signals or data signals with these in-vehicle devices 7760 .

[0187] The in-vehicle network I / F 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The in-vehicle network I / F 7680 transmits and receives signals in accordance with a predetermined protocol supported by the communication network 7010.

[0188] The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 in accordance with various programs based on information acquired via at least one of the general-purpose communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the in-vehicle device I / F 7660, and the in-vehicle network I / F 7680. For example, the microcomputer 7610 may calculate control target values ​​for the driving force generating device, the steering mechanism, or the braking device based on the acquired information inside and outside the vehicle, and output control commands to the drivetrain control unit 7100. For example, the microcomputer 7610 may perform cooperative control aimed at realizing functions of an Advanced Driver Assistance System (ADAS), including vehicle collision avoidance or impact mitigation, following driving based on the following distance, vehicle speed maintenance driving, vehicle collision warning, vehicle lane departure warning, etc. In addition, the microcomputer 7610 may perform cooperative control for the purpose of autonomous driving, in which the vehicle travels autonomously without relying on driver operation, by controlling a driving force generating device, a steering mechanism, a braking device, etc. based on information acquired about the vehicle's surroundings.

[0189] The microcomputer 7610 may generate three-dimensional distance information between the vehicle and objects such as surrounding structures and people, and create local map information including information about the vicinity of the vehicle's current location, based on information acquired via at least one of the general-purpose communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the in-vehicle device I / F 7660, and the in-vehicle network I / F 7680. Furthermore, the microcomputer 7610 may predict dangers, such as a vehicle collision, the approach of a pedestrian, or entry into a closed road, based on the acquired information, and generate a warning signal. The warning signal may be, for example, a signal for generating a warning sound or turning on a warning lamp.

[0190] The audio / image output unit 7670 transmits at least one audio and / or image output signal to an output device capable of visually or audibly notifying vehicle occupants or the outside of the vehicle of information. In the example of FIG. 23 , an audio speaker 7710, a display unit 7720, and an instrument panel 7730 are illustrated as output devices. The display unit 7720 may include, for example, at least one of an on-board display and a head-up display. The display unit 7720 may have an AR (Augmented Reality) display function. The output device may also be other devices, such as headphones, a wearable device such as an eyeglass-type display worn by the occupant, a projector, or a lamp. When the output device is a display device, the display device visually displays results obtained by various processes performed by the microcomputer 7610 or information received from other control units in various formats, such as text, images, tables, and graphs. When the output device is an audio output device, the audio output device converts audio signals, such as reproduced audio data or acoustic data, into analog signals and audibly outputs the analog signals.

[0191] In the example shown in FIG. 23 , at least two control units connected via the communication network 7010 may be integrated into a single control unit. Alternatively, each control unit may be composed of multiple control units. Furthermore, the vehicle control system 7000 may include another control unit not shown. In the above description, some or all of the functions performed by one of the control units may be performed by another control unit. In other words, as long as information is transmitted and received via the communication network 7010, predetermined arithmetic processing may be performed by one of the control units. Similarly, a sensor or device connected to one of the control units may be connected to another control unit, and multiple control units may transmit and receive detection information to and from each other via the communication network 7010.

[0192] The present technology can have the following configurations: [1] A LiDAR system including: a light source having a light-emitting surface composed of one or more light-emitting elements; a collimating optical element arranged on the optical axis of the light source; a reflective amplifying light-guiding element arranged on the optical axis of the light source between the light source and the collimating optical element, the reflective amplifying light-guiding element having an incident surface, a light guide path, and an output surface; a focusing optical element that focuses light reflected from an object to be measured; and a photodetector arranged on the optical axis of the focusing optical element and having a light detection surface composed of one or more light-receiving elements, wherein the reflective amplifying light-guiding element guides light incident on the incident surface from the light source to the collimating optical element by reflecting it within the light guide path. [2] The LiDAR system according to [1], wherein an inclination angle formed by a normal to the incident surface and a side surface of the light guide path of the reflective amplifying light-guiding element is smaller than a diffraction angle of light incident on the incident surface. [3] The LiDAR system according to [1] or [2], wherein the reflection-amplifying light-guiding element has two or more regions made of materials with different refractive indices. [4] The LiDAR system according to [3], wherein the two or more regions are formed continuously over at least a portion of the longitudinal range of the light guide along the light guiding direction. [5] The LiDAR system according to [4], wherein at least one of the two or more regions consists of two or more cylindrical sections formed over at least a portion of the longitudinal range of the light guide along the light guiding direction. [6] The LiDAR system according to [4] or [5], wherein at least one of the two or more regions is formed continuously over the entire longitudinal range of the light guide. [7] The LiDAR system according to any of [1] to [6], wherein the light guide is formed by connecting two or more sections along the light guiding direction, in which the inclination angles formed by the normal to the incident surface and the side surface of the light guide are different from each other. [8] The LiDAR system according to any one of [1] to [7], wherein the light guide path has an inclination angle formed between the normal to the incident surface and the side surface of the light guide path along the light guiding direction. [9] The LiDAR system according to any one of [1] to [8], wherein the output surface is disposed at the focal point of the collimating optical element.

[10] The LiDAR system according to any one of [1] to [9], wherein the light source and the reflection-amplifying light-guiding element are in contact at the incident surface.

[11] The LiDAR system according to any one of [1] to

[10] , wherein one or more adjustment media having the same refractive index are filled between the light source and the incident surface of the reflection-amplifying light-guiding element on the optical axis of the light source.

[12] The LiDAR system according to

[11] , wherein the refractive index of the adjustment media is between the equivalent refractive index of the light source and the refractive index of the material with the lowest refractive index among the materials forming the light guide path.

[13] The LiDAR system according to any one of [1] to

[12] , wherein the area of ​​the light-emitting surface that emits light from the light source and the area of ​​the incident surface are approximately the same.

[14] The LiDAR system according to any one of [1] to

[13] , wherein the area of ​​the output surface is larger than the area of ​​the incident surface.

[15] The LiDAR system according to

[14] , wherein the area of ​​the light-emitting surface that emits light from the light source is approximately the same as the area of ​​the incident surface.

[16] The LiDAR system according to

[15] , wherein the area of ​​the output surface is designed so that the range over which the reflected light is collected by the collecting optical element is approximately the same as the area of ​​the light detection surface.

[17] The LiDAR system according to any of

[14] to

[16] , wherein the reflective amplifying light-guiding element has a tapered shape.

[18] An optical component used in a LiDAR system, comprising: a light source having a light-emitting surface made of one or more light-emitting elements; and a reflective amplifying light-guiding element arranged on the optical axis of the light source, the reflective amplifying light-guiding element having an incident surface, a light guide path, and an output surface, wherein the reflective amplifying light-guiding element guides light in a specific direction by reflecting light that has entered the incident surface from the light source within the light guide path.

[19] A reflection-amplifying light-guiding element for use in a LiDAR system, having an incident surface, a light guide path, and an output surface, which guides light in a specific direction by reflecting light incident on the incident surface within the light guide path.

[20] A position detection sensor comprising the LiDAR system described in any of [1] to

[17] .

[21] A moving body comprising the position detection sensor described in

[20] .

[0193] 10, 10b LiDAR system 11 Light-emitting element 12 Reflection-amplifying light-guiding element 12-1 Incident surface 12-2 Light-guiding path 12-3 Output surface 13 Collimating optical element 14 Light-collecting optical element 15 Photodetector 16 Light-receiving element 17 Object to be measured (virtual subject surface, virtual object to be measured) 18 Optical component (light source-side optical component) 19 Light source 20 Position detection sensor A, B Optical axis X Normal to the incident surface α Diffraction angle β Inclination angle L Range of light collected by the light-collecting optical element

Claims

1. A LiDAR system comprising: a light source having a light-emitting surface consisting of one or more light-emitting elements; a collimating optical element arranged on the optical axis of the light source; a reflective amplifying light-guiding element arranged on the optical axis of the light source between the light source and the collimating optical element, the reflective amplifying light-guiding element having an incident surface, a light guide path, and an output surface; a focusing optical element that focuses reflected light from an object to be measured; and a photodetector arranged on the optical axis of the focusing optical element, the photodetector having a light detection surface consisting of one or more light-receiving elements, wherein the reflective amplifying light-guiding element guides light incident on the incident surface from the light source to the collimating optical element by reflecting it within the light guide path.

2. The LiDAR system of claim 1, wherein the inclination angle formed by the normal to the incident surface and the side surface of the light guide path of the reflective amplification light guide element is smaller than the diffraction angle of light incident on the incident surface.

3. The LiDAR system of claim 1 or 2, wherein the reflective amplifying light guide element has two or more regions made of materials with different refractive indices.

4. The LiDAR system of claim 3, wherein the two or more regions are formed continuously along the light guiding direction over at least a portion of the longitudinal range of the light guiding path.

5. The LiDAR system of claim 4, wherein at least one of the two or more regions is composed of two or more cylindrical sections formed along the light guiding direction over at least a portion of the longitudinal range of the light guiding path.

6. The LiDAR system of claim 4, wherein at least one of the two or more regions is formed continuously over the entire longitudinal range of the light guide path.

7. The LiDAR system described in claim 1, wherein the light guide path is formed by connecting two or more sections along the light guiding direction, the sections having different inclination angles formed by the normal to the incident surface and the side surface of the light guide path.

8. The LiDAR system of claim 1, wherein the inclination angle formed between the normal to the incident surface and the side surface of the light guide path changes along the light guiding direction.

9. The LiDAR system of claim 1, wherein the output surface is disposed at a focal point of the collimating optic.

10. The LiDAR system of claim 1, wherein the light source and the reflective amplifying light-guiding element are in contact at the incident surface.

11. The LiDAR system of claim 1, wherein on the optical axis of the light source, the space between the light source and the incident surface of the reflective amplifying light-guiding element is filled with one or more adjustment media having the same refractive index.

12. The LiDAR system of claim 11, wherein the refractive index of the adjustment medium has a value between the equivalent refractive index of the light source and the refractive index of the material with the lowest refractive index among the materials forming the light guide path.

13. The LiDAR system of claim 1, wherein the area of ​​the light-emitting surface from which the light of the light source is emitted is approximately the same as the area of ​​the incident surface.

14. The LiDAR system of claim 1, wherein an area of ​​the output face is greater than an area of ​​the entrance face.

15. The LiDAR system of claim 14, wherein the area of ​​the light-emitting surface from which the light of the light source is emitted and the area of ​​the incident surface are approximately the same.

16. The LiDAR system of claim 15, wherein the area of ​​the output surface is designed so that the range over which the reflected light is collected by the collecting optical element is approximately the same as the area of ​​the light detection surface.

17. The LiDAR system of claim 14, wherein the reflective amplifying light-guiding element is tapered.

18. An optical component used in a LiDAR system, comprising: a light source having a light-emitting surface consisting of one or more light-emitting elements; and a reflective amplifying light-guiding element arranged on the optical axis of the light source, the reflective amplifying light-guiding element having an incident surface, a light guide path, and an output surface, wherein the reflective amplifying light-guiding element guides light in a specific direction by reflecting light that has entered the incident surface from the light source within the light guide path.

19. A reflective amplification light-guiding element for use in a LiDAR system, having an incident surface, a light guide path, and an output surface, which guides light in a specific direction by reflecting light incident on the incident surface within the light guide path.

20. A position detection sensor comprising the LiDAR system of claim 1.

21. A moving object equipped with the position detection sensor according to claim 20.

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