Laser radar

Abstract

The utility model discloses a laser radar, which belongs to the related technical field of laser radars, and comprises an optical system, a laser radar detector and a laser, and the optical system comprises a receiving mirror group and a transmitting mirror group; wherein the receiving mirror group comprises a transmission reflecting mirror, a correction plate, a primary mirror and a secondary mirror which are sequentially arranged along an echo light beam transmission light path, the primary mirror is a concave spherical reflecting mirror, the secondary mirror is a plane reflecting mirror, the correction plate is a plano-convex lens, the spherical aberration during spherical reflection of the primary mirror can be accurately corrected by utilizing the arrangement of the correction plate, and accurate transmission and receiving of echo signals are ensured; meanwhile, the secondary mirror is arranged between the correction plate and the primary mirror, and the central through hole of the primary mirror is arranged, so that the optical path can be effectively folded, and the arrangement size of the receiving mirror group is shortened. The laser radar provided by the utility model is compact in structure and convenient to use, and can effectively reduce the transverse layout size of the laser radar while meeting the echo signal receiving precision, thereby providing assistance for the miniaturization design of products.

Description

Technical Field

[0001] The utility model belongs to the technical field related to laser radars, and specifically relates to a laser radar. Background Art

[0002] LiDAR is a sensing device that detects targets by emitting and receiving laser beams. By measuring the time required for the laser to hit the surface of the detection object and then reflect back, the distance between the LiDAR and the target object is calculated and data points are generated. The entire process usually obtains millions of data points to form a point cloud.

[0003] Based on their scanning methods, LiDAR can be generally categorized as mechanical, semi-solid-state, and fully solid-state. Semi-solid-state LiDAR is the most popular type, where the laser and receiver remain stationary, while scanning is achieved through the movement of moving parts such as rotating mirrors or MEMS galvanometers.

[0004] Currently, the receiving optical systems designed for semi-solid-state lidars mainly include conventional three-piece receiving mirrors and Newtonian telescopes. While both can meet the requirements of semi-solid-state lidars to a certain extent, they still have significant drawbacks. The three-piece receiving mirrors typically have an excessively long focal length, resulting in a long total optical path, excessive size, and difficulty in internal structure layout. In contrast, while the Newtonian telescope uses a reflector, which can shorten the system construction to a certain extent, it still has drawbacks such as a small field of view and spherical aberration on the system axis, which also has certain application limitations. Utility Model Content

[0005] In response to one or more of the above-mentioned defects or improvement needs of the prior art, the present invention provides a laser radar that can accurately realize the convergence and detection of the laser radar echo beam while reducing the layout size of each component of the receiving mirror group, thereby ensuring the accuracy of the laser radar's detection of the echo beam and meeting the miniaturization design requirements of the laser radar.

[0006] To achieve the above-mentioned object, the present invention provides a laser radar, comprising an optical system suitable for the laser radar, a laser radar detector and a laser;

[0007] The optical system includes a receiving mirror group and a transmitting mirror group for transmitting the detection laser; the receiving mirror group includes a transmission reflector, a correction plate, a primary mirror and a secondary mirror arranged in sequence along the transmission optical path of the echo beam;

[0008] The central area of ​​the transmission reflector is provided with a reflective film, thereby forming a reflective mirror in the central area of ​​the transmission reflector; correspondingly, the peripheral area of ​​the transmission reflector is provided with an anti-reflection film, thereby forming a transmission mirror in the peripheral area of ​​the transmission reflector;

[0009] The transmissive reflector is tilted relative to the correction plate, and the correction plate, the primary mirror and the secondary mirror are coaxially arranged; the secondary mirror is arranged between the correction plate and the primary mirror, and a through hole facing the secondary mirror is coaxially opened in the middle of the primary mirror;

[0010] The correction plate is a plano-convex lens, which is an aspheric mirror; the primary mirror is a concave spherical reflector, whose reflective surface is a concave spherical surface facing the secondary mirror; and the secondary mirror is a plane reflector, whose reflective surface faces the reflective surface of the primary mirror and is directly opposite to the through hole; the central axis of the transmission reflector intersects with the central axis of the correction plate and forms an angle of 45° with each other, and the center of the transmission reflector is located on the central axis of the correction plate;

[0011] One end of the transmitting mirror assembly is used to be assembled with a laser that emits a detection laser, and the other end thereof is arranged corresponding to the transmission reflector, so that the detection laser emitted after being transmitted from the transmitting mirror assembly can be reflected by the transmission reflector and then emitted toward the object to be detected; the detection laser emitted from the transmitting mirror assembly and the mirror surface of the transmission reflector are at a 45° angle to each other, and the detection laser emitted by the transmission reflector is parallel to the central axis of the correction plate;

[0012] The laser radar detector is arranged on a side of the primary mirror away from the secondary mirror, and the laser is arranged on an end of the transmitting mirror group away from the transmission reflector.

[0013] As a further improvement of the present invention, the outer diameter of the primary mirror is between 35 and 45 mm, and the inner diameter of the through hole is between 16 and 18 mm;

[0014] Correspondingly, the outer diameter of the secondary mirror is 22-25 mm.

[0015] As a further improvement of the present invention, the outer diameter of the correction plate is equivalent to the outer diameter of the primary mirror, that is, the outer diameter of the correction plate is 35~45mm.

[0016] As a further improvement of the present invention, the field of view of the receiving lens assembly is 20°.

[0017] As a further improvement of the present invention, the laser radar detector is coaxially arranged with the primary mirror.

[0018] The above-mentioned improved technical features can be combined with each other as long as they do not conflict with each other.

[0019] In general, the above technical solutions conceived by the present invention have the following beneficial effects compared with the prior art:

[0020] (1) The laser radar in the present invention has a receiving mirror group including a transmission reflector, a correction plate, a primary mirror and a secondary mirror arranged in sequence along the transmission optical path of the echo light beam, wherein the primary mirror is a concave spherical reflector, the secondary mirror is a plane reflector, and the correction plate is a plano-convex lens. By setting the correction plate, the spherical aberration of the primary mirror during spherical reflection can be accurately corrected, thereby ensuring the utilization rate of the echo signal and improving the use accuracy of the receiving mirror group. At the same time, by coordinating the setting of the secondary mirror between the correction plate and the primary mirror and the setting of the central through hole of the primary mirror, the optical path can be effectively folded, the layout size of the receiving mirror group can be shortened, and conditions are provided for the miniaturization design of the laser radar optical system and the entire machine.

[0021] (2) The laser radar in the present invention can further ensure the reliability and accuracy of the echo light beam transmission by the receiving mirror group by optimizing the size parameters and setting form of each component, thereby achieving high-quality reception and utilization of the echo signal.

[0022] (3) The optical system of the laser radar in the present invention includes a receiving mirror group and a transmitting mirror group that are arranged in combination with each other. The entire optical system has a compact structure and high operating precision, which can fully meet the miniaturization design requirements of the laser radar, optimize the structural design of the laser radar, and promote the development of the laser radar technology.

[0023] (4) The laser radar in the present invention has a compact structure and is easy to set up. It utilizes the optimized design of the receiving mirror group and the transmitting mirror group in the optical system. While ensuring the accuracy of detecting laser emission and transmission as well as echo beam transmission and reception, it fully considers the compactness of the optical system, provides convenience for the miniaturization design of the laser radar, and promotes the development and application of laser radar.

[0024] (5) The laser radar in the utility model has a compact structure and is easy to use. It can fully meet the application requirements of the receiving mirror group in the laser radar. While meeting the echo signal reception accuracy, it effectively reduces the lateral layout size of the laser radar, provides support for the miniaturization design of the product, and has good practical value and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic diagram of the structural composition of a receiving mirror assembly suitable for laser radar in an embodiment of the present utility model;

[0027] Figure 2 This is a schematic diagram of the structure of an optical system suitable for laser radar in an embodiment of the present utility model;

[0028] In all the drawings, the same reference numerals represent the same technical features, specifically:

[0029] 1. Transmitting reflector; 2. Correction plate; 3. Primary mirror; 4. Secondary mirror; 5. Echo beam; 6. LiDAR detector; 7. Transmitting mirror group; 8. Detection laser. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0031] In the description of the present invention, it should be understood that, unless otherwise expressly specified and limited, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this utility model, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0033] In this utility model, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0034] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0035] Example:

[0036] See also Figure 1 In the preferred embodiment of the present invention, the receiving mirror group suitable for the laser radar is used to receive the echo light beam 5 reflected by the object to be detected by the laser radar, and the laser radar detector 6 arranged in the laser radar is used to detect the echo light beam 5 to determine the distance between the object to be detected and the laser radar, thereby completing the working process of the laser radar.

[0037] Specifically, the receiving mirror assembly in the preferred embodiment is as follows Figure 1 As shown in the figure, it includes a transmission reflector 1, a correction plate 2, a primary mirror 3 and a secondary mirror 4 arranged in sequence along the transmission optical path of the echo light beam 5, wherein the secondary mirror 4 is arranged between the correction plate 2 and the primary mirror 3, and the correction plate 2, the secondary mirror 4 and the primary mirror 3 are coaxially arranged.

[0038] Meanwhile, the transmission reflector 1 in the preferred embodiment is arranged on the side of the correction plate 2 away from the secondary mirror 4, with its axis and the central axis of the correction plate 2 forming a certain angle, which is 45° in the preferred embodiment.

[0039] by Figure 1 Taking the preferred embodiment shown as an example, when the axis of the correction plate 2 is horizontally arranged, that is, the correction plate 2 is vertically arranged, the transmission reflector 1 is inclined at 45° relative to the correction plate 2 .

[0040] In more detail, in actual arrangement, the center of the transflector 1 is located on the central axis of the correction plate 2 .

[0041] In the specific setting, the central area of ​​the transmission reflector 1 is set as a reflector, and its peripheral area is set as a transmission mirror; at this time, a reflective film is set for its central area, and an anti-reflection film is set for its peripheral area, so that the detection laser 8 emitted through the transmitting mirror group 7 can be reflected to the target object through the central area of ​​the transmission reflector 1, and the echo light beam 5 reflected back by the target object can be transmitted to the correction plate 2 through the peripheral area of ​​the transmission reflector 1.

[0042] More specifically, in the preferred embodiment, primary mirror 3 is a concave spherical reflector having a concave spherical reflective surface disposed toward the side of secondary mirror 4. A through-hole of a predetermined size is coaxially defined in the center of primary mirror 3 and coaxially aligned with secondary mirror 4, allowing the return beam 5 reflected by secondary mirror 4 to pass through the through-hole toward a lidar detector 6 on the side of primary mirror 3 facing away from secondary mirror 4.

[0043] Furthermore, the secondary mirror 4 in the preferred embodiment is a plane reflector, whose reflective surface faces the reflective surface of the primary mirror 3, and the reflective surface of the secondary mirror 4 is opposite to the through hole in the middle of the primary mirror 3, and is aligned with the laser radar detector 6 arranged on the side of the primary mirror 3 away from the secondary mirror 4 through the through hole.

[0044] Since the primary mirror 3 has a spherical reflective surface, spherical aberration will occur when reflecting the echo beam 5. Therefore, a correction plate 2 is provided between the transmission reflector 1 and the primary mirror 3 to correct the spherical aberration during spherical reflection from the primary mirror 3, thereby improving the echo signal utilization rate of the receiving system.

[0045] Specifically, in a preferred embodiment, the correction plate 2 is a plano-convex lens, which is an aspherical mirror, and its outer diameter preferably corresponds to the outer diameter of the primary mirror 3 .

[0046] In a specific preferred embodiment, the outer diameter of the primary mirror 3 is between 35 and 45 mm, and the inner diameter of the central through hole is preferably between 16 and 18 mm. Meanwhile, the outer diameter of the secondary mirror 4 in this preferred embodiment is preferably between 22 and 25 mm. Accordingly, the outer diameter of the correction plate 2 is also preferably between 35 and 45 mm.

[0047] Furthermore, the field of view of the receiving lens assembly in the preferred embodiment is ±10°. Figure 1 In the preferred embodiment shown, the incident angle of the light beam of the receiving mirror assembly is 0° (relative to the central axis of the primary mirror 3). Thus, for the receiving mirror assembly in the preferred embodiment, the incident angle of the light beam can be relatively Figure 1 The center line shown is deflected 10° upward or downward, thereby forming a 20° field of view.

[0048] The combination of the correction plate 2, primary mirror 3, and secondary mirror 4 in the preferred embodiment allows the echo beam 5 to be directed toward the laser radar detector 6 after "secondary reflection." By utilizing the "secondary folding" of the beam's optical path, the actual layout dimensions of the receiving mirror assembly can be shortened while maintaining the total optical path length, thereby ensuring the accuracy of echo signal reception while achieving a miniaturized design of the receiving mirror assembly. Simultaneously, the corresponding arrangement of the transmission reflector 1 facilitates the integrated arrangement of the transmitting mirror assembly 7 while ensuring the transmission requirements of the echo beam 5, thereby facilitating the optimized design of the laser radar optical system structure.

[0049] In actual settings, the receiving mirror group is assembled with the laser radar detector 6 at one end of which the primary mirror 3 is provided, so that the echo light beam 5 reflected by the secondary mirror 4 and passing through the middle hole of the primary mirror 3 can be focused on the laser radar detector 6, and then the laser radar detector 6 completes the detection of the echo light beam 5.

[0050] Furthermore, as a specific application of the receiving mirror assembly in the preferred embodiment of the present utility model, in the preferred embodiment, an optical system suitable for laser radar is further proposed.

[0051] Specifically, the optical system in the preferred embodiment includes the following Figure 1 In addition to the receiving mirror group, the transmitting mirror group 7 is also included, which is arranged corresponding to the transmission reflector 1 in the receiving mirror group. One end of the transmitting mirror group 7 is preferably arranged corresponding to the laser of the laser radar, and is used to receive and transmit the detection laser 8 emitted by the laser; accordingly, the other end of the transmitting mirror group 7 is arranged corresponding to the transmission reflector 1, so that the detection laser 8 emitted after being transmitted through the transmitting mirror group 7 can be emitted toward the transmission reflector 1, and after being reflected by the transmission reflector 1, it can be emitted toward the object to be detected.

[0052] Correspondingly, the detection laser 8 is reflected by the object to be detected after reaching it, forming an echo beam 5, and then the echo beam 5 passes through the transmission reflector 1, the correction plate 2, the primary mirror 3, and the secondary mirror 4 in sequence and is received by the laser radar detector 6, thereby completing one working process of the laser radar.

[0053] In a specific configuration, the detection laser light 8 emitted from the emission mirror assembly 7 is preferably at a 45-degree angle to the mirror surface of the transmission reflector 1, and the detection laser light 8 reflected by the transmission reflector 1 is parallel to the central axis of the correction plate 2. In this case, the return beam 5 transmitted by the transmission reflector 1 and the detection laser light 8 reflected by the transmission reflector 1 are parallel to each other.

[0054] In a preferred embodiment, the corresponding setting of the transmission reflector 1 in the receiving mirror group is utilized so that the receiving mirror group can be quickly combined with the transmitting mirror group 7 to form an optical system with laser transceiver functions, which provides convenience for the design of the laser radar and makes the optical system of the laser radar more compact.

[0055] As another aspect of a preferred embodiment of the present invention, a laser radar is provided, comprising the aforementioned optical system, with a laser radar detector 6 and a laser correspondingly disposed for the receiving mirror assembly and the transmitting mirror assembly 7 in the optical system. The laser radar detector 6 is disposed on the side of the primary mirror 3 facing away from the secondary mirror 4, and is preferably coaxial with the primary mirror 3 so that the echo beam 5 reflected by the secondary mirror 4 can be projected onto the laser radar detector 6. Accordingly, a laser is disposed on the end of the transmitting mirror assembly 7 facing away from the transflector 1, and is used to generate a detection laser 8 and direct it toward the transmitting mirror assembly 7.

[0056] By utilizing the corresponding settings of the optical system, the laser radar detector 6, and the laser, the generation and transmission process of the detection laser 8 and the transmission and reception process of the echo beam 5 can be accurately completed, thereby completing the laser radar detection of the corresponding object.

[0057] The laser radar in the utility model has a compact structure and is easy to use. It can fully meet the application of the receiving mirror group in the laser radar. While meeting the echo signal reception accuracy, it effectively reduces the lateral layout size of the laser radar, provides support for the miniaturization design of the product, and has good practical value and application prospects.

[0058] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A laser radar, characterized in that: including optical systems, lidar detectors, and lasers suitable for lidar; The optical system includes a receiving mirror group and a transmitting mirror group for transmitting the detection laser; the receiving mirror group includes a transmission reflector, a correction plate, a primary mirror and a secondary mirror arranged in sequence along the transmission optical path of the echo beam; The central area of ​​the transmission reflector is provided with a reflective film, thereby forming a reflective mirror in the central area of ​​the transmission reflector; correspondingly, the peripheral area of ​​the transmission reflector is provided with an anti-reflection film, thereby forming a transmission mirror in the peripheral area of ​​the transmission reflector; The transmissive reflector is tilted relative to the correction plate, and the correction plate, the primary mirror and the secondary mirror are coaxially arranged; the secondary mirror is arranged between the correction plate and the primary mirror, and a through hole facing the secondary mirror is coaxially opened in the middle of the primary mirror; The correction plate is a plano-convex lens, which is an aspheric mirror; the primary mirror is a concave spherical reflector, whose reflective surface is a concave spherical surface facing the secondary mirror; and the secondary mirror is a plane reflector, whose reflective surface faces the reflective surface of the primary mirror and is directly opposite to the through hole; the central axis of the transmission reflector intersects with the central axis of the correction plate and forms an angle of 45° with each other, and the center of the transmission reflector is located on the central axis of the correction plate; One end of the transmitting mirror assembly is used to be assembled with a laser that emits a detection laser, and the other end thereof is arranged corresponding to the transmission reflector, so that the detection laser emitted after being transmitted from the transmitting mirror assembly can be reflected by the transmission reflector and then emitted toward the object to be detected; the detection laser emitted from the transmitting mirror assembly and the mirror surface of the transmission reflector are at a 45° angle to each other, and the detection laser emitted by the transmission reflector is parallel to the central axis of the correction plate; The laser radar detector is arranged on a side of the primary mirror away from the secondary mirror, and the laser is arranged on an end of the transmitting mirror group away from the transmission reflector.

2. The laser radar according to claim 1, characterized in that The outer diameter of the primary mirror is between 35 and 45 mm, and the inner diameter of the through hole is 16 to 18 mm; accordingly, the outer diameter of the secondary mirror is 22 to 25 mm.

3. The laser radar according to claim 2, characterized in that The outer diameter of the correction plate is comparable to that of the primary mirror, that is, the outer diameter of the correction plate is 35-45 mm.

4. The laser radar according to any one of claims 1 to 3, characterized in that The field of view of the receiving lens assembly is 20°.

5. The laser radar according to any one of claims 1 to 3, characterized in that The laser radar detector is coaxially arranged with the primary mirror.

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