Optical system and laser radar
By using microlens and microprism components in lidar, a panoramic pitch field of view can be achieved, solving the problem of limited measurement range of lidar and realizing miniaturization and cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-06
- Publication Date
- 2026-04-03
AI Technical Summary
Existing lidar has a limited pitch field of view, which cannot achieve a panoramic view (0° to 180°), thus limiting the measurement range.
By employing microlens and microprism components, a panoramic pitch field of view is achieved through the reflection of light within the microprism and the refraction of light by the microprism. Combined with the miniaturized design of the microlens and microprism components, manufacturing costs are reduced.
It achieves a panoramic pitch field of view of 0° to 180° for lidar, increasing the measurement range and applicability, while meeting the requirements of miniaturization and cost reduction.
Smart Images
Figure CN224081840U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of lidar technology, and more particularly to an optical system and lidar. Background Technology
[0002] With the development and application of lidar technology, the market demand for lidar with a large pitch field of view is increasing. However, the pitch field of view of lidar currently on the market is limited, for example, the pitch field of view range is 0° to 150°, and it cannot achieve a panoramic pitch field of view (0° to 180°), which limits the measurement range of lidar.
[0003] Therefore, how to enable lidar to have a panoramic pitch field of view has become an urgent technical problem to be solved. Utility Model Content
[0004] The main objective of this application is to provide an optical system and a lidar, such that the lidar using the optical system has a panoramic pitch field of view, thereby increasing the measurement range of the lidar.
[0005] In a first aspect, one embodiment of this application provides an optical system applied to lidar, the optical system comprising:
[0006] A microlens assembly, comprising at least one microlens array, wherein the microlenses in the microlens array correspond to the light-emitting unit or the receiving sensing unit of the lidar, the light-emitting unit or the receiving sensing unit is located at the focal point of the microlens, and the microlens array is used to collimate or converge the light emitted by the light-emitting unit to the receiving sensing unit.
[0007] A microprism assembly includes a light-transmitting substrate and a microprism array formed on a surface of the light-transmitting substrate away from the microlens assembly. The microprism array includes reflective microprisms and refractive microprisms. The reflective microprisms are disposed near the edge of the light-transmitting substrate, and the refractive microprisms are disposed near the center of the light-transmitting substrate. The microprisms in the microprism array correspond to the microlenses in the microlens array.
[0008] The optical system is mounted vertically on the lidar. By reflecting light through the reflective microprism and refracting light through the refracting microprism, the lidar can achieve a panoramic pitch field of view.
[0009] In one embodiment, the bevel of the reflective microprism is coated with an internal reflective film.
[0010] In one embodiment, the tilt angle of the reflective microprism increases sequentially from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, wherein the tilt angle of the reflective microprism is the angle between the inclined surface of the reflective microprism and the surface of the light-transmitting substrate.
[0011] In one embodiment, the tilt angle of the reflective microprism is greater than or equal to the critical angle of refraction of the reflective microprism, wherein the tilt angle of the reflective microprism is the angle between the inclined surface of the reflective microprism and the surface of the light-transmitting substrate.
[0012] In one embodiment, the bevel of the refractive microprism is coated with an antireflective film.
[0013] In one embodiment, the tilt angle of the refractive microprism decreases sequentially from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, wherein the tilt angle of the refractive microprism is the angle between the inclined surface of the refractive microprism and the surface of the light-transmitting substrate.
[0014] In one embodiment, in the microlens assembly, at least one of the microlenses does not correspond to a microprism in the microprism array but corresponds to the direct-light region of the light-transmitting substrate, so that light can directly pass through the direct-light region and be emitted directly.
[0015] In one embodiment, the direct-light region is located near the center of the light-transmitting substrate, and the reflective microprism and the refractive microprism are symmetrically arranged about the direct-light region.
[0016] In one embodiment, the optical system satisfies the following relationship:
[0017]
[0018] Wherein, d1 is the diameter of the microlens, d2 is the width of the reflecting or refracting microprism corresponding to the microlens, the width being the width of the surface of the reflecting or refracting microprism in contact with the light-transmitting substrate, f is the focal length of the microlens, and β is the divergence angle of the light-emitting unit.
[0019] Secondly, one embodiment of this application also provides a lidar, which includes an optical system provided in any embodiment of this application.
[0020] This application provides an optical system that can be vertically mounted on a lidar. By reflecting light through reflective microprisms and refracting light through refractive microprisms within the optical system, the lidar using this optical system can achieve a panoramic pitch field of view from 0° to 180°, increasing the measurement range and applicability of the lidar. Simultaneously, because the microlens and microprism components can be made very thin, the size of the optical system can be made very small, meeting the miniaturization requirements of lidar. Furthermore, the low manufacturing cost of the microlens and microprism components also reduces the manufacturing cost of the lidar with a panoramic pitch field of view. Attached Figure Description
[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a partial structural schematic diagram of a lidar provided in one embodiment of this application;
[0023] Figure 2 for Figure 1 The diagram shows the field of view range of the lidar.
[0024] Figure 3 This is a partial structural schematic diagram of a lidar provided in one embodiment of this application;
[0025] Figure 4 for Figure 1 The diagram shows a partial structural schematic of a lidar.
[0026] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0028] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0029] Please refer to Figure 1 , Figure 1 This is a partial structural schematic diagram of a lidar provided in one embodiment of this application. Figure 1 The diagram only shows a portion of the structure of the lidar 100. It is understood that the actual lidar 100 also includes other components or structures not shown in the diagram.
[0030] The lidar 100 includes an optical system 10, a light source 20, a rotary motor 30, and a housing 40. The optical system 10, the light source 20, and the rotary motor 30 are mounted inside the housing 40. It is understood that in order for the light emitted by the light source 20 to reach the object under test after passing through the optical system 10, the housing 40 needs to be able to transmit light; for example, the housing 40 can be a transparent housing.
[0031] The optical system 10 and the light source 20 are mounted vertically on the rotary motor 30 of the lidar 100, such as... Figure 1 As shown. The optical system 10 includes a microlens assembly 11 and a microprism assembly 12. The light source 20 can be a laser light source, which includes multiple light-emitting units.
[0032] In one embodiment, the light-emitting unit can be a vertical-cavity surface-emitting laser (VCSEL), or other lasers, such as an edge-emitting laser (EEL). The specific type of the light-emitting unit can be set according to actual needs, and no specific limitation is made here.
[0033] The light-emitting unit is located at the focal point of the microlens in the microlens assembly 11, so that the microlens collimates the light emitted by the light-emitting unit.
[0034] After collimation, the light rays are incident on the microprism assembly 12. The reflected light from the reflecting microprisms and the refracted light from the refracting microprisms within the assembly 12 increase the pitch field of view of the lidar 100, allowing it to range from 0° to 180°, thus achieving a panoramic pitch field of view. When the rotary motor 30 drives the optical system 10 and the light source 20 to rotate 360°, the lidar 100 can perform a comprehensive scan of its surroundings, forming a panoramic view. Figure 2 The field of view range is shown.
[0035] exist Figure 1 In the lidar 100 shown, the optical system 10 is used in the transmitting system of the lidar 100. Of course, the optical system 10 can also be used in the receiving system of the lidar 100. Figure 3 As shown, Figure 3This is a partial structural schematic diagram of a lidar provided in one embodiment of this application. It should be noted that... Figure 3 The lidar 100 shown only illustrates a portion of its structure. In an actual lidar 100, the lidar 100 may include other structures or components.
[0036] exist Figure 3 The lidar 100 also includes a sensor 50, which includes multiple receiving sensing units for receiving light reflected back from the object under test.
[0037] In one embodiment, the sensor 50 may be an avalanche photodiode (APD).
[0038] When the optical system 10 is used in the receiving system, the microlens in the microlens assembly 11 corresponds to the receiving sensing unit of the lidar 100. The receiving sensing unit is located at the focal point of the microlens in the microlens assembly 11, so that the microlens can converge the light reflected back from the object under test and converge it onto the receiving sensing unit.
[0039] The light reflected back by the object under test passes through the internal reflection of the reflecting microprism and the refraction of the refracting microprism in the optical system 10, and then enters the microlens assembly 11. After the converging effect of the microlens assembly 11, the light is focused onto each receiving and sensing unit in the sensor 50, thereby realizing the reception of signals in the panoramic range of 0° to 180°.
[0040] The optical system 10 in various embodiments of this application will now be described in detail with reference to the accompanying drawings.
[0041] Please refer to Figure 4 As shown, Figure 4 for Figure 1 The diagram shows a partial structural schematic of the lidar. In this embodiment, the optical system 10 is applied to the lidar 100. It is understood that the optical system 10 can also be applied to devices such as 3D SLAM scanners and 3D spatial scanners.
[0042] The optical system 10 includes a microlens assembly 11 and a microprism assembly 12.
[0043] The microlens assembly 11 includes a first light-transmitting substrate 111 and at least one microlens array 112, wherein the microlenses in the microlens array 112 correspond to the light-emitting unit or the receiving sensing unit of the lidar 100, the light-emitting unit or the receiving sensing unit is located at the focal point of the microlens, and the microlens array 112 is used to collimate the light emitted by the light-emitting unit or to converge the light to the receiving sensing unit.
[0044] In one embodiment, when the light-emitting unit is a vertical cavity surface-emitting laser, the microlens array 112 can be a microspherical lens array or a microaspherical lens array.
[0045] In one embodiment, when the light-emitting unit is a side-emitting laser, the microlens assembly 11 includes two first transparent substrates 111 and two microlens arrays 112, wherein the two microlens arrays 112 are a fast-axis collimating microcylindrical lens array and a slow-axis collimating microcylindrical lens array, respectively, and the two microlens arrays 112 are formed on the surfaces of the two first transparent substrates 111 that are away from the light-emitting unit. In this way, after the laser is emitted from the light-emitting unit, it passes sequentially through the first transparent substrate 111, the fast-axis collimating microcylindrical lens array, the other first transparent substrate 111, and the slow-axis collimating microcylindrical lens array.
[0046] like Figure 4 As shown, the microprism assembly 12 includes a light-transmitting substrate 121 and a microprism array 122 formed on the surface of the light-transmitting substrate 121 away from the microlens assembly 11. The light-transmitting substrate 121 may also be referred to as a second light-transmitting substrate.
[0047] It should be noted that, Figure 4 The number of microprisms, microlenses, and light-emitting units in the lidar 100 shown is just an example; the specific number can be set according to actual needs.
[0048] In this embodiment, the microprisms in the microprism array 122 correspond to the microlenses in the microlens array 112. The microprisms in the microprism array 122 include a reflecting microprism 1221 and a refractive microprism 1222. The reflecting microprism 1221 is disposed near the edge of the light-transmitting substrate 121, and the refractive microprism 1222 is disposed near the center of the light-transmitting substrate 121.
[0049] In other words, such as Figure 4 As shown, from the edge of the light-transmitting substrate 121 to the center direction (i.e. Figure 4 (As indicated by arrows A and B), the reflecting microprism 1221 is closer to the edge of the light-transmitting substrate 121 than the refractive microprism 1222, and the refractive microprism 1222 is closer to the center of the light-transmitting substrate 121 than the reflecting microprism 1221.
[0050] In one embodiment, the inclined surface of the reflective microprism 1221 is coated with an internal reflective film. Of course, in other embodiments, the inclined surface of the reflective microprism 1221 may not be coated with an internal reflective film, or may be partially coated with an internal reflective film; no specific limitations are imposed here.
[0051] like Figure 4As shown, in the direction from the edge of the light-transmitting substrate 121 to the center of the light-transmitting substrate 121 (i.e. Figure 4 (As indicated by arrows A and B), the tilt angle α of the reflective microprism 1221 increases sequentially, wherein the tilt angle α of the reflective microprism 1221 is the angle between the inclined surface of the reflective microprism 1221 and the surface of the light-transmitting substrate 121.
[0052] In one embodiment, the tilt angle α of the reflecting microprism 1221 is greater than or equal to the critical refraction angle of the reflecting microprism 1221.
[0053] In one embodiment, the inclined surface of the refractive microprism 1222 is coated with an antireflective film. Of course, in other embodiments, the inclined surface of the refractive microprism 1222 may not be coated with an antireflective film, as long as its refractive function can be achieved and refracted light at the corresponding angle can be obtained.
[0054] like Figure 4 As shown, in the direction from the edge of the light-transmitting substrate 121 to the center of the light-transmitting substrate 121, the tilt angle θ of the refractive microprism 1222 decreases sequentially, wherein the tilt angle θ of the refractive microprism 1222 is the angle between the inclined surface of the refractive microprism 1222 and the surface of the light-transmitting substrate 121.
[0055] like Figure 4 As shown, in the microlens assembly 11, there is at least one microlens that does not correspond to the microprisms in the microprism array 122 but corresponds to the direct-light region C of the light-transmitting substrate 121, so that light can directly pass through the direct-light region C and be directly emitted, thereby forming a light with a 90° pitch field of view.
[0056] In one embodiment, the direct-light region C is located near the center of the light-transmitting substrate 121, so that both the reflective microprism 1221 and the refractive microprism 1222 can be symmetrically arranged about the direct-light region C. For example, as Figure 4As shown, the reflecting microprisms 1221 located on the left and right sides of the direct-light region C are symmetrically arranged about the direct-light region C. Similarly, the refractive microprisms 1222 located on the left and right sides of the direct-light region C are symmetrically arranged about the direct-light region C. In this way, the reflecting microprism 1221 and the refractive microprism 1222 located on the right side of the direct-light region C perform internal reflection and refraction of the laser beam after it is aligned with the direct-light region C, respectively. The elevation field of view of the emitted light beam can be achieved from 0° to 90°. The reflecting microprism 1221 located on the left side of the direct-light region C... 1221 and the refractive microprism 1222 respectively perform internal reflection and refraction of the laser beam after it is directly aligned with the laser. The elevation field of view of the emitted light can be from 90° to 180°. At the same time, since the light beam after it is directly aligned with the laser does not refract, the elevation field of view of the light beam emitted from the light beam after it is directly aligned with the laser can be 90°. Therefore, the lidar 100 using this optical system 10 can achieve a panoramic elevation field of view from 0° to 180°, which increases the measurement range and applicability of the lidar 100.
[0057] In one embodiment, the optical system 10 must satisfy the following relationship:
[0058]
[0059] Wherein, d1 is the diameter of the microlens, d2 is the width of the reflecting microprism 1221 or the refractive microprism 1222 corresponding to the microlens, the width of the surface of the reflecting microprism 1221 or the refractive microprism 1222 in contact with the light-transmitting substrate 121, f is the focal length of the microlens, and β is the divergence angle of the light-emitting unit.
[0060] In one embodiment, the microprism assembly 12 can be made of a high refractive index material, for example, the material of the microprism assembly 12 can be flint glass, specifically, such as H-ZLAF92.
[0061] from Figure 2 As can be seen, the optical system 10 in this embodiment enables the lidar 100 to achieve a panoramic pitch field of view from 0° to 180°, meeting the large pitch field of view requirement of the lidar 100 and increasing the measurement range and applicability of the lidar 100. At the same time, since the microlens assembly 11 and the microprism assembly 12 can be made very thin, the size of the optical system 10 can be made very small, which is beneficial to the miniaturization of the lidar 100. In addition, the manufacturing cost of the optical system 100 is also low, reducing the manufacturing cost of the lidar 100.
[0062] The foregoing disclosure provides many different implementations or examples for carrying out different structures of this application. To simplify the disclosure, the components and arrangements of specific examples are described above. Of course, these are merely examples and are not intended to limit the scope of this application. Any non-substantial changes and substitutions made by those skilled in the art based on this application are within the scope of protection claimed by this application.
[0063] Furthermore, reference numerals and / or reference letters may be repeated in different examples in this application. Such repetition is for simplification and clarity purposes and does not in itself indicate a relationship between the various embodiments and / or settings discussed. In addition, this application provides examples of various specific processes and materials; however, those skilled in the art will recognize the application of other processes and / or the use of other materials.
Claims
1. An optical system characterized by comprising: The optical system is applied to a laser radar, and the optical system comprises: a microlens assembly comprising at least one microlens array, wherein the microlenses in the microlens array correspond to light-emitting units or receiving sensing units of the laser radar, the light-emitting units or receiving sensing units are located at the focal points of the microlenses, and the microlens array is used for collimating light rays emitted by the light-emitting units or converging the light rays onto the receiving sensing units; a microlens assembly comprising at least one microlens array, wherein the microlenses in the microlens array correspond to light-emitting units or receiving sensing units of the laser radar, the light-emitting units or receiving sensing units are located at the focal points of the microlenses, and the microlens array is used for collimating light rays emitted by the light-emitting units or converging the light rays onto the receiving sensing units; the optical system is mounted on the laser radar in a vertical direction, and light rays are internally reflected by the reflective microlenses and refracted by the refractive microlenses, so that the laser radar achieves a panoramic elevation field of view.
2. The optical system of claim 1, wherein The slope of the reflective microlenses is coated with an internal reflection film.
3. The optical system of claim 1, wherein, In a direction from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, the tilt angles of the reflective microlenses gradually increase, wherein the tilt angle of the reflective microlenses is the included angle between the slope of the reflective microlenses and the surface of the light-transmitting substrate.
4. The optical system of claim 1, wherein The tilt angle of the reflective microlenses is greater than or equal to the critical angle of refraction of the reflective microlenses, wherein the tilt angle of the reflective microlenses is the included angle between the slope of the reflective microlenses and the surface of the light-transmitting substrate.
5. The optical system of claim 1, wherein, The slope of the refractive microlenses is coated with an anti-reflection film.
6. The optical system of claim 1, wherein, In a direction from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, the tilt angles of the refractive microlenses gradually decrease, wherein the tilt angle of the refractive microlenses is the included angle between the slope of the refractive microlenses and the surface of the light-transmitting substrate.
7. The optical system of claim 1, wherein In the microlens assembly, at least one microlens does not correspond to a microlens in the microlens array but corresponds to a direct transmission area of the light-transmitting substrate, so that light rays directly transmit out through the direct transmission area.
8. The optical system of claim 7, wherein, The direct transmission area is located near the center of the light-transmitting substrate, and the reflective microlenses and the refractive microlenses are symmetrically arranged about the direct transmission area.
9. The optical system according to any one of claims 1 to 8, characterized in that The optical system satisfies the following relationship: wherein d1 is the diameter of the microlens, d2 is the width of the reflective microlenses or the refractive microlenses corresponding to the microlenses, the width is the width of the surface of the reflective microlenses or the refractive microlenses in contact with the light-transmitting substrate, f is the focal length of the microlens, and β is the divergence angle of the light-emitting units.
10. A lidar, comprising: The laser radar comprises the optical system according to any one of claims 1 to 9.