Optical system and laser radar

Abstract

The invention provides an optical system and a laser radar, the optical system comprises a light source, a micro lens assembly and a micro prism assembly, and the micro lens assembly is used for collimating light emitted by the light source; the microprism assembly comprises a light-transmitting substrate, a first microprism array, a second microprism array and a third microprism array, the first microprism array is formed on the first surface of the light-transmitting substrate, the second microprism array is formed on the second surface of the light-transmitting substrate, and the third microprism array is formed on the first surface and / or the second surface of the light-transmitting substrate; microprisms in the first microprism array, the second microprism array and the third microprism array correspond to microlenses in the microlens array; the optical system is installed on the laser radar in the horizontal direction, and the pitching field angle of the laser radar is increased through the external reflection effect of the first microprism array, the internal reflection effect of the second microprism array and the refraction effect of the third microprism array.

Description

Technical Field

[0001] The present application relates to the technical field of lidar, and particularly to an optical system and a lidar. Background Art

[0002] With the development and application of lidar technology, the market has an increasing demand for lidars with large vertical and horizontal field of view angles. Currently, in order to increase the vertical and horizontal field of view angles, the optomechanical module of the lidar on the market is integrally inclined on the lidar. Although this inclined setting can increase the vertical and horizontal field of view angles to a certain extent, it also causes the size of the optomechanical module to increase rapidly, making the entire lidar larger and not meeting the requirement of machine miniaturization.

[0003] Therefore, how to enable the lidar to have both a large vertical and horizontal field of view angle and be miniaturized has become a technical problem that urgently needs to be solved. Summary of the Invention

[0004] The main purpose of the present application is to provide an optical system and a lidar, so that the lidar applying the optical system has both a large vertical and horizontal field of view angle and can be miniaturized.

[0005] In a first aspect, an embodiment of the present application provides an optical system, which is applied to a lidar. The optical system includes:

[0006] A light source, the light source including a plurality of light-emitting units;

[0007] A microlens assembly, the microlens assembly including at least one microlens array. Among them, the microlenses in the microlens array correspond to the light-emitting units, the light-emitting units are located at the foci of the microlenses, and the microlens array is used to collimate the light emitted by the light-emitting units;

[0008] A microprism assembly, the microprism assembly including a light-transmitting substrate, a first microprism array, a second microprism array, and a third microprism array. Among them, the first microprism array is formed on the first surface of the light-transmitting substrate, the second microprism array is formed on the second surface of the light-transmitting substrate, the third microprism array is formed on the first surface and / or the second surface of the light-transmitting substrate. The first surface is the surface of the light-transmitting substrate facing the microlens array, the second surface is the surface of the light-transmitting substrate facing away from the microlens array, and the microprisms in the first microprism array, the second microprism array, and the third microprism array correspond to the microlenses in the microlens array;

[0009] The optical system is mounted on the lidar in the horizontal direction, and the light collimated by external reflection of the first micro-prism array, the light collimated by internal reflection of the second micro-prism array, and the light collimated by refraction of the third micro-prism array are used to increase the elevation and depression field of view angles of the lidar.

[0010] In one embodiment, the inclined surface of the micro-prism in the first micro-prism array is coated with an external reflection film, or the inclined surface of the micro-prism in the second micro-prism array is coated with an internal reflection film, or the inclined surface of the micro-prism in the third micro-prism array is coated with an anti-reflection film.

[0011] In one embodiment, the micro-prisms in the first micro-prism array include at least two first micro-prisms, and in the direction from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, the first inclination angles of the inclined surfaces of at least two of the first micro-prisms decrease in sequence, where the first inclination angle is the angle between the inclined surface of the first micro-prism and the first surface of the light-transmitting substrate.

[0012] In one embodiment, the first micro-prism near the edge of the light-transmitting substrate in the first micro-prism array is a triangular micro-prism, and the other first micro-prisms are trapezoidal micro-prisms.

[0013] In one embodiment, the micro-prisms in the first micro-prism array include at least one first micro-prism, the first micro-prism includes at least two of the inclined surfaces, the first inclination angles of at least two of the inclined surfaces are different, and in the direction from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, the first inclination angles of at least two of the inclined surfaces decrease in sequence, where the first inclination angle is the angle between the inclined surface of the first micro-prism and the first surface of the light-transmitting substrate.

[0014] In one embodiment, the micro-prisms in the second micro-prism array include at least one second micro-prism, and the second inclination angle of the inclined surface of the second micro-prism is greater than or equal to the refractive critical angle of the second micro-prism, where the second inclination angle is the angle between the inclined surface of the second micro-prism and the second surface of the light-transmitting substrate.

[0015] In one embodiment, when the number of the second micro-prisms is at least two, in the direction from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, the second inclination angles of at least two of the second micro-prisms increase in sequence.

[0016] In one embodiment, in the micro-lens assembly, there is at least one micro-lens that does not correspond to the micro-prism but corresponds to the light-transmitting substrate, so that the light collimated by the micro-lens directly passes through the light-transmitting substrate and shines out.

[0017] In one embodiment, the optical system satisfies the following relationship:

[0018]

[0019] Wherein, d1 is the diameter of the microlens, d2 is the width of the microprism corresponding to the microlens, and the width is the width of the surface of the 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.

[0020] In a second aspect, an embodiment of the present application further provides a lidar, which includes an optical system provided in any embodiment of the present application.

[0021] An embodiment of the present application provides an optical system, which can be installed on a lidar along the horizontal direction. By the light rays collimated by external reflection of the first microprism array, the light rays collimated by internal reflection of the second microprism array, and the light rays collimated by refraction of the third microprism array in the optical system, the technical effect of increasing the vertical field of view angle of the lidar can be achieved. The optical system does not need to be installed on the lidar obliquely, and a large vertical field of view angle can be achieved. At the same time, since the microlens assembly and the microprism assembly in the optical system can be made very thin, the size of the optical system can be made very small, meeting the miniaturization requirements of the lidar. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 It is a schematic structural diagram of an optical system provided by an embodiment of the present application;

[0024] Figure 2 For Figure 1 It is a schematic structural diagram of the microprism assembly in the optical system shown;

[0025] Figure 3 It is a schematic structural diagram of an optical system provided by an embodiment of the present application;

[0026] Figure 4 It is a schematic structural diagram of an optical system provided by an embodiment of the present application;

[0027] Figure 5 It is a schematic structural diagram of an optical system provided by an embodiment of the present application;

[0028] Figure 6 It is a schematic structural diagram of an optical system provided by an embodiment of the present application;

[0029] Figure 7 A structural schematic diagram of an optical system provided by an embodiment of the present application;

[0030] Figure 8 is Figure 1 A partial structural schematic diagram of the optical system shown;

[0031] Figure 9 is Figure 1 A schematic diagram of the field of view angle range of the optical system shown.

[0032] The realization of the purpose of the present application, functional characteristics and advantages will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0033] Next, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0034] Next, some embodiments of the present application will be described in detail with reference to the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0035] Please refer to Figure 1 and Figure 2 , Figure 1 A structural schematic diagram of an optical system provided by an embodiment of the present application, Figure 2 is Figure 1 A structural schematic diagram of the micro prism assembly in the optical system shown. The optical system 100 can be applied to devices such as lidar, three-dimensional SLAM scanners, and three-dimensional space scanners. The optical system 100 includes a light source 10, a micro lens assembly 20, and a micro prism assembly 30.

[0036] The light source 10 can be a laser light source, which includes a plurality of light emitting units 11. In Figure 1 the structural schematic diagram shown, only ten light emitting units 11 are schematically shown. It can be understood that the number and arrangement of the light emitting units 11 can be set according to actual needs and will not be specifically limited here.

[0037] In one embodiment, the light-emitting unit 11 may be a Vertical-Cavity Surface-Emitting Laser (VCSEL), or may also be other lasers. For example, it may also be an Edge-Emitting Laser (EEL). The specific type of the light-emitting unit 11 may be set according to actual requirements and will not be specifically limited herein.

[0038] The microlens assembly 20 includes a first light-transmitting substrate 21 and at least one microlens array 22. In Figure 1 the shown structural schematic diagram, the number of the microlens arrays 22 is one, and the microlens array 22 is formed on a surface of the first light-transmitting substrate 21 away from the light-emitting unit 11 for collimating the laser emitted by the light-emitting unit 11.

[0039] The microlenses in the microlens array 22 correspond to the light-emitting unit 11, and the light-emitting unit 11 is located at the focal point of the microlens, so that the microlens collimates the laser emitted by the corresponding light-emitting unit 11.

[0040] In one embodiment, when the light-emitting unit 11 is a vertical-cavity surface-emitting laser, the microlens array 22 may be a micro-spherical lens array or a micro-asphere lens array. The microlenses in the microlens array 22 may correspond to the light-emitting unit 11 one by one, and at this time, the number of microlenses is the same as the number of light-emitting units 11. It can be understood that the corresponding relationship between the microlenses and the light-emitting unit 11 is not limited to one-to-one correspondence, and may also be other corresponding relationships, which will not be specifically limited herein.

[0041] In one embodiment, when the light-emitting unit 11 is an edge-emitting laser, at least one of the microlens arrays 22 may be a combination of a fast-axis collimating micro-cylindrical lens array and a slow-axis collimating micro-cylindrical lens array. That is to say, two first light-transmitting substrates 21 are included in the microlens assembly 20, and the fast-axis collimating micro-cylindrical lens array and the slow-axis collimating micro-cylindrical lens array are respectively formed on the surfaces of the two first light-transmitting substrates 21 away from the light-emitting unit 11. In this way, after the laser is emitted from the light-emitting unit 11, it sequentially passes through the first light-transmitting substrate 21, the fast-axis collimating micro-cylindrical lens array, the other first light-transmitting substrate 21, and the slow-axis collimating micro-cylindrical lens array. At this time, one microlens in the microlens array 22 may correspond to multiple light-emitting units 11.

[0042] As Figure 1 and Figure 2 shown, the microprism assembly 30 includes a light-transmitting substrate 31 and a first microprism array 32, a second microprism array 33, and a third microprism array 34 formed on the light-transmitting substrate 31. Among them, the light-transmitting substrate 31 may also be referred to as a second light-transmitting substrate.

[0043] As Figure 1 shown, the first micro - prism array 32 is formed on the first surface of the light - transmissive substrate 31, where the first surface is the surface of the light - transmissive substrate 31 facing the microlens array 22, that is, the surface facing the light source 10. The inclined surfaces of the micro - prisms in the first micro - prism array 32 are coated with an external reflection film, which is used for external reflection of the light collimated by the microlens assembly 20, so as to form a light beam with a negative field of view angle.

[0044] It should be noted that the negative field of view angle refers to the angle between the reflected light and the horizontal plane in the clockwise direction with the plane where the light - transmissive substrate 31 is located as the horizontal plane. That is to say, when the optical system 100 is installed on the lidar in the horizontal direction, laser light rays for scanning can be obtained below the horizontal plane, increasing the elevation field of view angle.

[0045] In one embodiment, the micro - prisms in the first micro - prism array 32 include at least two first micro - prisms 321. In the direction from the edge of the light - transmissive substrate 31 to the center of the light - transmissive substrate 31, the first inclination angles θ1 of the inclined surfaces of at least two of the first micro - prisms 321 decrease in sequence, where the first inclination angle θ1 is the angle between the inclined surface of the first micro - prism 321 and the first surface of the light - transmissive substrate 31. For example, in Figure 1 the two first micro - prisms 321 shown, in the direction from right to left, the first inclination angles θ1 of the inclined surfaces of the two first micro - prisms 321 decrease in sequence. In this way, light beams with different negative field of view angles can be obtained through different first micro - prisms 321.

[0046] In one embodiment, the first micro - prism 321 near the edge of the light - transmissive substrate 31 in the first micro - prism array 32 is a triangular micro - prism, and the other first micro - prisms 321 are trapezoidal micro - prisms. For example, in Figure 1 the two first micro - prisms 321 shown, the heights of the two adjacent side surfaces of the trapezoidal micro - prism and the triangular micro - prism are set to the same value, so as to avoid problems such as the light reflected by the trapezoidal micro - prism 321 being blocked by the triangular micro - prism.

[0047] In one embodiment, the micro - prisms in the first micro - prism array 32 include at least one first micro - prism 321, and the first micro - prism 321 includes at least two inclined surfaces. Among them, the first inclination angles θ1 of at least two inclined surfaces are different, and in the direction from the edge of the light - transmissive substrate 31 to the center of the light - transmissive substrate 31, the first inclination angles θ1 of at least two inclined surfaces decrease in sequence.

[0048] For example, as Figure 3 shown, Figure 3 is a schematic structural diagram of an optical system provided by an embodiment of the present application. In Figure 3In the optical system 100 shown, the first micro - prism array 32 includes a first micro - prism 321, and the first micro - prism 321 has two inclined planes. The first inclination angles θ1 of the two inclined planes are different, and obviously, the first inclination angle θ1 of the inclined plane closer to the edge of the light - transmissive substrate 31 is greater than the first inclination angle θ1 of the other inclined plane. Different inclined planes externally reflect the collimated light to form different light beams with negative field angles.

[0049] It can be understood that Figure 3 The number, shape of the first micro - prism 321 shown, and the number of inclined planes, etc., are just one of many embodiments. The number, shape of the first micro - prism 321, and the number of inclined planes can be designed according to actual needs and are not specifically limited herein.

[0050] As Figure 1 shown, the second micro - prism array 33 is formed on the second surface of the light - transmissive substrate 31, where the second surface is the surface of the light - transmissive substrate 31 facing away from the microlens array 22, that is, the surface facing away from the light source 10. The inclined planes of the micro - prisms in the second micro - prism array 33 are coated with an internal reflection film for internally reflecting the light collimated by the microlens assembly 20, thereby increasing the positive field angle above the horizontal plane.

[0051] In an embodiment, the micro - prisms in the second micro - prism array 33 include at least one second micro - prism 331, and the second inclination angle θ2 of the inclined plane of the second micro - prism 331 is greater than or equal to the refractive critical angle of the second micro - prism 331, where the second inclination angle θ2 is the angle between the inclined plane of the second micro - prism 331 and the second surface of the light - transmissive substrate 31.

[0052] Furthermore, when the number of the second micro - prisms 331 is at least two, in the direction from the edge of the light - transmissive substrate 31 to the center of the light - transmissive substrate 31, the second inclination angles θ2 of at least two second micro - prisms 331 increase in sequence. For example, as Figure 1 shown, Figure 1 shows three second micro - prisms 331. In the direction from right to left, the second inclination angles θ2 of the three second micro - prisms 331 increase in sequence. In this way, through the internal reflection effect, the light beams of the optical system 100 at positive and small - angle field angles can be increased.

[0053] It should be noted that the inclined planes of the micro - prisms in the second micro - prism array 33 may not be coated with an internal reflection film, or may be partially coated with an internal reflection film, which is not specifically limited herein.

[0054] As Figure 1As shown, the third micro - prism array 34 is formed on the first surface and the second surface of the light - transmissive substrate 31. An anti - reflection film is coated on the inclined surface of the micro - prisms in the third micro - prism array 34. Herein, the micro - prisms in the third micro - prism array 34 can be referred to as the third micro - prisms 341. The third micro - prism array 34 is used to refract the collimated light, thereby forming refracted light in different directions.

[0055] It can be understood that in other embodiments, the inclined surface of the third micro - prism 341 may not be coated with an anti - reflection film, as long as its refraction function can be achieved and refracted light at corresponding angles can be obtained.

[0056] In addition, the third micro - prism array 34 is not limited to being formed on the first surface and the second surface of the light - transmissive substrate 31, and can also be formed on the first surface or the second surface of the light - transmissive substrate 31. For example, as Figure 4 shown, Figure 4 is a schematic structural diagram of an optical system provided by an embodiment of the present application. The third micro - prism array 34 is formed on the second surface of the light - transmissive substrate 31. Another example, as Figure 5 shown, Figure 5 is a schematic structural diagram of an optical system provided by an embodiment of the present application. The third micro - prism array 34 is formed on the first surface of the light - transmissive substrate 31.

[0057] In Figure 1 the optical system shown, the micro - prisms in the first micro - prism array 32, the second micro - prism array 33, and the third micro - prism array 34 correspond to the micro - lenses in the micro - lens array 22. Among them, the corresponding relationship between the micro - prism and the micro - lens can include many types. For example, the corresponding relationship between the micro - prism and the micro - lens can be a one - to - one correspondence. As Figure 1 shown, each micro - prism corresponds to a micro - lens. Another example, the corresponding relationship between the micro - prism and the micro - lens can be a one - to - many relationship. As Figure 3 shown, Figure 3 shows a first micro - prism 321, and the first micro - prism 321 corresponds to two micro - lenses. The corresponding relationship between the micro - prism and the micro - lens can be designed according to actual needs and is not specifically limited herein.

[0058] In one embodiment, in the micro - lens assembly 20, there is at least one micro - lens that does not correspond to a micro - prism but corresponds to the light - transmissive substrate 31, so that the light collimated by the micro - lens directly passes through the light - transmissive substrate 31 and shines directly out. For example, in Figure 1Counting from left to right, the third microlens does not correspond to the microprism, but corresponds to the area marked as A in the light-transmitting substrate 31, so that the light collimated by the third microlens can be directly transmitted from the light-transmitting substrate 31 to form a light with a field of view angle of 90° with the horizontal plane, so that the pitch field of view of the optical system 100 has a field of view angle of 90°.

[0059] exist Figures 1 to 5 In the optical system 100 shown, two third microprisms 341 are arranged on the left side of the A area directly corresponding to the microlens in the light-transmitting substrate 31, and the two third microprisms 341 are used to obtain a field of view greater than 90°. When the optical system 100 is mounted on a laser radar in the horizontal direction, a large elevation field of view of less than 0° to greater than 90° can be obtained through the external reflection effect of the first microprism array 32, the internal reflection effect of the second microprism array 33, and the refraction effect of the third microprism array 34.

[0060] Of course, in other embodiments, the optical system 100 may not be provided with microprisms for obtaining a viewing angle greater than 90°. Figure 6 As shown, Figure 6 A schematic diagram of the structure of an optical system provided in an embodiment of the present application. Figure 6 The optical system 100 shown can achieve a large pitch angle of less than 0° to 90°. When the optical system 100 is installed on the rotating motor of the laser radar, the rotating motor can drive the optical system 100 to rotate 360° in all directions, forming a 360° azimuth angle and a large pitch angle of less than 0° to 90°. However, in actual applications, due to factors such as the rotation speed and movement speed of the laser radar, Figure 6 The optical system 100 shown may not have enough time to scan. Figures 1 to 5 The optical system 100 shown in the figure can cover a wider area due to the addition of microprisms for obtaining a field of view angle greater than 90°, avoiding the above-mentioned situation of not having enough time to scan, and improving the scanning quality and scanning accuracy of the laser radar.

[0061] It should be noted that the A region in the light-transmitting substrate 31 directly corresponding to the microlens is not limited to Figures 1 to 5 The position shown in the figure can also be other positions, for example, Figure 1 The A area in the figure is placed on the left side of the microprism for obtaining a field angle greater than 90°.

[0062] In addition, the microprism used to obtain a viewing angle greater than 90° is not limited to the microprism of Figures 1 to 5 The third microprism 341 shown in the figure can also be realized by utilizing the internal reflection effect of the second microprism array 33. Figure 7 As shown,Figure 7 This is a schematic structural diagram of the optical system provided by the embodiment of the present application. In Figure 7 In the optical system 100 shown, the micro prism for obtaining a field of view angle greater than 90° is the second micro prism 331.

[0063] In one embodiment, in order to improve the quality of the field of view spot of the optical system 100, the following relational expression is satisfied between the diameter d1 of the micro lens in the micro lens assembly 20 and the width d2 of the micro prism corresponding to the micro lens:

[0064]

[0065] Wherein, the width of the micro prism is the width of the surface of the micro prism in contact with the light-transmitting substrate 31, f is the focal length of the micro lens, and β is the divergence angle of the light-emitting unit 11.

[0066] In one embodiment, as Figure 1 shown, in the first micro prism array 32, the second micro prism array 33 and the third micro prism array 34, the widths of multiple micro prisms are the same, that is, the widths of the first micro prism 321, the second micro prism 331 and the third micro prism 341 are the same.

[0067] In one embodiment, a material with a high refractive index can be used to make the micro prism assembly 30. For example, the material of the micro prism assembly 30 can be flint glass, specifically, such as, H-ZLAF92.

[0068] In order to verify that when the optical system 100 in this embodiment is installed on the lidar in the horizontal direction, a large downward and upward field of view angle can be obtained, the following gives a specific test.

[0069] In this test, the optical system 100 as Figure 1 shown is adopted, and at the same time referring to Figure 8 , Figure 8 is Figure 1 shown as a partial structural schematic diagram of the optical system. The light-emitting unit 11 is a VCSEL, the optical wavelength is 905 nm, the distance between adjacent two light-emitting units 11 is 2 mm, the light-emitting size of the light-emitting unit 11 is 20 μm, the full-width at half-maximum divergence angle of the light-emitting unit 11 is 16°, and after collimation by the micro lens assembly 20, the divergence angle is required to be reduced to 0.2°; the focal length f of the micro lens is 5.7 mm, the diameter d1 of the micro lens is 1.8 mm, the distance between adjacent two micro lenses is 2 mm, and the thickness of the first light-transmitting substrate 21 is 1.5 mm. The material of the micro prism in the micro prism assembly 30 is H-ZLAF92, and the width d2 of all micro prisms is 1.8 mm. In Figure 1In the micro-lens assembly 30 shown, there are 9 micro-prisms. Counting from right to left, the second micro-prism is a trapezoidal micro-prism. Except for this, the other micro-prisms are triangular micro-prisms. The heights h of the triangular micro-prisms are 1.31 mm, 1.8 mm, 2.38 mm, 3.53 mm, 1.2 mm, 0.584 mm, 0.584 mm, and 0.989 mm in sequence from right to left. The height h1 of the trapezoidal micro-prism is 1.4 mm, and the height h2 is 2.31 mm.

[0070] The laser emitted by the light-emitting unit 11, after being collimated by the lens assembly 20, is incident into the micro-prism assembly 30, and forms light beams with different field angles after internal reflection, external reflection, and refraction. From right to left, the angles of the emitted light beams corresponding to the triangular micro-prisms are -18°, 0°, 18°, 36°, 54°, 72°, 108°, and 120° in sequence, and the angle of the emitted light beam corresponding to the trapezoidal micro-prism is -36°; in addition, Figure 1 In the micro-lens assembly 20 shown, the third micro-lens from left to right does not correspond to a micro-prism, but corresponds to the A area of the light-transmitting substrate 31. The angle of the emitted light beam corresponding to the third micro-lens is 90°. Therefore, Figure 1 The optical system 100 shown can form a large depression and elevation field angle from -36° to 120°; when the optical system 100 is horizontally installed on the rotating motor of the lidar and rotates 360°, it will form a Figure 9 field angle range as shown.

[0071] From Figure 9 it can be seen that the optical system 100 in the embodiment of the present application can achieve a large depression and elevation field angle greater than 150° without being installed obliquely, meeting the requirements of the large depression and elevation field angle of the lidar. At the same time, since the micro-lens assembly 20 and the micro-prism assembly 30 can be made very thin, the size of the optical system 100 can be made very small, which is beneficial to the miniaturization of the lidar. In addition, the manufacturing cost of the optical system 100 is also low, reducing the manufacturing cost of the lidar.

[0072] An embodiment of the present application further provides a lidar, which applies the optical system described in any of the above embodiments. For the sake of simplicity of the specification, the structure and working principle of the optical system adopted by this lidar can refer to the foregoing embodiments and will not be elaborated here.

[0073] Since this lidar applies the optical system provided by the present application, it can not only meet the requirements of a large depression and elevation field angle, but also meet the requirements of miniaturization. At the same time, the manufacturing cost is also low, which is beneficial to marketization.

[0074] The foregoing disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, components and settings of specific examples are described above. Of course, they are merely examples and are not intended to limit the present application. Any non-substantive changes and substitutions made by those skilled in the art based on the present application fall within the scope of protection required by the present application.

[0075] In addition, the present application may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplification and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

Claims

1. An optical system, characterized in that: Applied to laser radar, the optical system includes: A light source, the light source comprising a plurality of light-emitting units; A microlens assembly, the microlens assembly comprising at least one microlens array, wherein the microlenses in the microlens array correspond to the light-emitting units, the light-emitting units are located at the focus of the microlenses, and the microlens array is used to collimate the light emitted by the light-emitting units; A microprism assembly, the microprism assembly comprising a light-transmitting substrate, a first microprism array, a second microprism array and a third microprism array, wherein the first microprism array is formed on a first surface of the light-transmitting substrate, the second microprism array is formed on a second surface of the light-transmitting substrate, the third microprism array is formed on the first surface and / or the second surface of the light-transmitting substrate, the first surface is a surface of the light-transmitting substrate facing the microlens array, the second surface is a surface of the light-transmitting substrate facing away from the microlens array, and the microprisms in the first microprism array, the second microprism array and the third microprism array correspond to the microlenses in the microlens array; The optical system is installed on the laser radar in the horizontal direction, and increases the pitch field angle of the laser radar by externally reflecting the collimated light from the first microprism array, internally reflecting the collimated light from the second microprism array, and refracting the collimated light from the third microprism array.

2. The optical system according to claim 1, characterized in that The inclined surfaces of the microprisms in the first microprism array are coated with an external reflective film, or the inclined surfaces of the microprisms in the second microprism array are coated with an internal reflective film, or the inclined surfaces of the microprisms in the third microprism array are coated with an anti-reflection film.

3. The optical system according to claim 2, characterized in that The microprisms in the first microprism array include at least two first microprisms, and in the direction from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, the first inclination angles of the inclined surfaces of at least two of the first microprisms decrease successively, wherein the first inclination angle is the angle between the inclined surface of the first microprism and the first surface of the light-transmitting substrate.

4. The optical system according to claim 3, characterized in that The first microprisms in the first microprism array close to the edge of the light-transmitting substrate are triangular microprisms, and the other first microprisms are trapezoidal microprisms.

5. The optical system according to claim 2, characterized in that The microprisms in the first microprism array include at least one first microprism, the first microprism includes at least two inclined surfaces, the first inclination angles of at least two inclined surfaces are different, and in the direction from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, the first inclination angles of at least two inclined surfaces decrease successively, wherein the first inclination angle is the angle between the inclined surface of the first microprism and the first surface of the light-transmitting substrate.

6. The optical system according to claim 1, characterized in that The microprisms in the second microprism array include at least one second microprism, and the second inclination angle of the inclined surface of the second microprism is greater than or equal to the critical angle of refraction of the second microprism, wherein the second inclination angle is the angle between the inclined surface of the second microprism and the second surface of the light-transmitting substrate.

7. The optical system according to claim 6, characterized in that When the number of the second microprisms is at least two, in the direction from the edge of the light-transmitting substrate to the center of the light-transmitting substrate, the second inclination angles of at least two of the second microprisms increase sequentially.

8. The optical system according to claim 1, characterized in that In the microlens assembly, there is at least one microlens that does not correspond to the microprism but corresponds to the light-transmitting substrate, so that the light collimated by the microlens directly passes through the light-transmitting substrate and is emitted directly.

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 microprism corresponding to the microlens, the width is the width of the surface of the microprism in contact with the transparent substrate, f is the focal length of the microlens, and β is the divergence angle of the light-emitting unit.

10. A laser radar, characterized in that: The laser radar comprises the optical system according to any one of claims 1 to 9.

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