A packaging shell for a lidar and its manufacturing method

Abstract

This application relates to the field of lidar technology and provides a lidar packaging shell and its fabrication method. The packaging shell includes: a metal base, a metal wall, multiple ceramic strips, an optical window, and a shaped sealing ring. The metal wall is disposed around the mounting surface of the metal base. The ceramic strips are assembled on a first side and a second side of the metal wall, with the first side opposite to the second side. The optical window, made of a sapphire crystal sheet, is welded to a third side of the metal wall and is adjacent to the first side. The shaped sealing ring is located above the metal wall and is welded to the metal wall and the ceramic strips. The method of this application can solve the problems of eye safety issues associated with lasers, as well as the problems of large packaging structure volume and low device integration.

Description

Technical Field

[0001] This application belongs to the field of lidar technology, and particularly relates to a lidar packaging shell and its manufacturing method. Background Technology

[0002] Currently, the light sources used in vehicle-mounted LiDAR systems are mostly the same as those in robotic vacuum cleaners, employing 905nm EEL lasers. This poses eye safety concerns, especially at working distances exceeding 150m, where the optical power of a 905nm laser exceeds the threshold for human eye safety. Therefore, lasers within the eye-safe wavelength range must be used. 1550nm is a typical representative of the eye-safe wavelength range. Under the same spot size and pulse width conditions, the maximum permissible exposure and maximum permissible peak optical power of a 1550nm laser are several orders of magnitude higher than those of a 905nm laser.

[0003] At the same power level safe for human eyes, a 905nm LiDAR can hardly detect an object about 10cm high on a highway more than 200m away. However, a 1550nm LiDAR can increase the detection distance to over 300m. But 1550nm LiDAR generally uses fiber lasers as its light source. Conventional fiber lasers are mostly packaged in metal shells with round leads, resulting in large size and low device integration. Summary of the Invention

[0004] To overcome the problems existing in related technologies, this application provides a packaging shell for a lidar and its manufacturing method, which can solve the problems of eye safety of lasers, large packaging structure volume, and low device integration.

[0005] This application is achieved through the following technical solution:

[0006] In a first aspect, embodiments of this application provide a packaging shell for a lidar, including: a metal base, a metal wall, multiple ceramic strips, a light window, and an irregularly shaped sealing ring;

[0007] The metal wall is set around the mounting surface of the metal base;

[0008] Ceramic strips are fitted onto the first and second sides of the metal wall; the first and second sides are opposite to each other.

[0009] The light window is welded to the third side of the metal wall and is made of a thin sapphire crystal sheet; the third side is adjacent to the first side.

[0010] The irregularly shaped sealing ring is located above the metal wall and is welded to the metal wall and ceramic strip.

[0011] In one possible implementation, the first side of the metal wall is provided with a first U-shaped opening;

[0012] The first U-shaped opening is used to assemble the first ceramic strip;

[0013] The width of the first U-shaped opening is the same as the width of the first ceramic strip;

[0014] The height of the first U-shaped opening is greater than the height of the first ceramic strip, and the upper surface of the first ceramic strip is a first preset distance away from the upper surface of the first U-shaped opening.

[0015] In one possible implementation, a second U-shaped opening is provided on the second side of the metal wall;

[0016] The second U-shaped opening is symmetrically arranged with respect to the first U-shaped opening;

[0017] The second U-shaped opening is used to assemble the second ceramic strip;

[0018] The width of the second U-shaped opening is the same as the width of the second ceramic strip;

[0019] The height of the second U-shaped opening is greater than the height of the second ceramic strip; the upper surface of the second ceramic strip is a second preset distance away from the upper surface of the first U-shaped opening.

[0020] In one possible implementation, the irregularly shaped sealing ring is welded around the top surface of the metal wall;

[0021] The first side of the irregular sealing ring is provided with a protruding thin sheet of a first preset size; the height of the thin sheet of the first preset size is the same as the first preset distance, and it is welded to the first ceramic strip;

[0022] The second side of the irregular sealing ring is provided with a protruding sheet of a second preset size; the height of the sheet of the second preset size is the same as the second preset distance, and it is welded to the second ceramic strip.

[0023] In one possible implementation, a chamfer is provided at the junction of the thin sheet of the irregular sealing ring and the metal wall.

[0024] In one possible implementation, the first side of the metal wall is provided with a plurality of first U-shaped openings, and each first U-shaped opening is spaced a third preset distance apart;

[0025] The second side of the metal wall is provided with multiple second U-shaped openings, and each second U-shaped opening is spaced a fourth preset distance apart.

[0026] In one possible implementation, the third side of the metal wall is provided with a light-transmitting hole for installing a light window;

[0027] Semi-circular stress buffer grooves are provided at the four corners of the light-transmitting hole.

[0028] Secondly, embodiments of this application provide a method for preparing a lidar enclosure, comprising: welding a metal wall to the periphery of the mounting surface of a metal base;

[0029] Ceramic strips are welded to the first and second sides of the metal wall; the first and second sides are opposite to each other.

[0030] The irregularly shaped sealing ring is welded to the metal wall and the top of the ceramic strip;

[0031] The light window is welded to the third side of the metal wall; the light window is made of a thin sapphire crystal sheet; the third side is adjacent to the first side.

[0032] In one possible implementation, the ceramic strip is made of alumina ceramic material and is prepared using low-temperature co-fired ceramic technology.

[0033] In one possible implementation, the welding method for welding the metal wall to the metal base, welding the ceramic strip to the first and second sides of the metal wall, and welding the irregular sealing ring to the top of the metal wall and the ceramic strip is high-temperature brazing, and the solder is silver-copper material.

[0034] It is understandable that the beneficial effects of the second aspect mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here.

[0035] The beneficial effects of the embodiments in this application compared with the prior art are:

[0036] In this embodiment, by setting a sapphire crystal sheet as a light window, the wavelength range of the transmitted light can be set within the safe range for the human eye. Then, multiple ceramic strips are encapsulated with an irregularly shaped sealing ring, reducing the volume of the encapsulation material and improving the integration of the device.

[0037] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this specification. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the packaging shell of a lidar provided in one embodiment of this application;

[0040] Figure 2 This is a schematic diagram of the structure of the irregular sealing ring separated from the metal wall according to an embodiment of this application;

[0041] Figure 3 This is a schematic diagram of the packaging shell of a lidar having a pair of ceramic strips according to an embodiment of this application;

[0042] Figure 4 This is a schematic diagram of the structure of an irregularly shaped sealing ring provided in one embodiment of this application;

[0043] Figure 5 This is a schematic diagram of a semi-circular stress buffer groove provided in an embodiment of this application. Detailed Implementation

[0044] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0045] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0046] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0047] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0048] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0049] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0050] LiDAR, short for "Light Detection and Ranging," formerly known as photoradar, is a type of radar that operates in the infrared and visible light bands. It's an optical remote sensing technology that obtains target-related information by detecting the scattered light characteristics of distant targets. With the development and application of ultrashort pulse laser technology, high-sensitivity signal detection, and high-speed data acquisition systems, LiDAR has become an important active remote sensing tool due to its high measurement accuracy, fine temporal and spatial resolution, and large detection range.

[0051] LiDAR is a system that integrates laser, GPS, and IMU (Inertial Measurement Unit) technologies. Compared to ordinary radar, LiDAR has advantages such as higher resolution, better concealment, and stronger anti-interference capabilities. With the continuous development of technology, LiDAR is being used more and more widely, and can be seen in fields such as robotics, autonomous driving, and driverless vehicles.

[0052] Currently, the light sources used in vehicle-mounted LiDAR systems are mostly the same as those in robotic vacuum cleaners, employing 905nm EEL lasers. This poses eye safety concerns, especially at working distances exceeding 150m, where the optical power of the 905nm laser exceeds the threshold for human eye safety. Therefore, lasers in the eye-safe wavelength range must be used. 1550nm is a typical example of an eye-safe wavelength range. Under the same spot size and pulse width conditions, the maximum permissible exposure and maximum permissible peak optical power of a 1550nm laser are several orders of magnitude higher than those of a 905nm laser.

[0053] Vehicle-mounted LiDAR is a mobile 3D laser scanning system that can emit and receive laser beams, analyze the return time of the laser after encountering a target object, calculate the relative distance between the target object and the vehicle, and use the collected information such as the 3D coordinates and reflectivity of a large number of dense points on the surface of the target object to quickly reconstruct the 3D model of the target and various map data, establish a 3D point cloud map, and draw an environmental map to achieve the purpose of environmental perception.

[0054] There are two main types of lidar detection technology: Time-of-Flight (TOF) and Frequency-Modulated Continuous Wave (FMCW). TOF calculates distance by multiplying the time of flight of the light pulse between the target and the lidar by the speed of light. TOF lidar employs pulse amplitude modulation technology and is therefore also known as AM lidar. FMCW primarily works by transmitting and receiving continuous laser beams, interfering the reflected light with the local light, and using frequency mixing detection technology to measure the frequency difference between the transmitted and received beams. The distance to the target is then calculated from this frequency difference. A comparison of the two methods follows:

[0055] 1) TOF light waves are easily affected by ambient light interference, while FMCW has strong anti-interference capabilities.

[0056] 2) The signal-to-noise ratio of TOF is too low, while the signal-to-noise ratio of FMCW is very high.

[0057] 3) TOF has low velocity dimension data quality, while FMCW can obtain velocity dimension data for each pixel.

[0058] 4) TOF is difficult to be compatible with OPA (Optical Phased Array, LiDAR) scanning structures, while FMCW is naturally more suitable for OPA.

[0059] 5) FMCW can achieve a higher degree of "chip-based" integration.

[0060] A 1550nm laser light source is also the light source chosen by some automotive LiDAR products. The reason is that the 1550nm laser is far from the visible light spectrum absorbed by the human eye. Compared with a 905nm laser, a 1550nm laser of the same power can improve eye safety by 40 times.

[0061] At the same power level suitable for human eye safety, a 905nm LiDAR can hardly detect an object about 10cm high on a highway more than 200m away, but a 1550nm LiDAR can increase the detection distance to over 300m. Furthermore, a 1550nm LiDAR, combined with Frequency Modulated Continuous Wave (FMCW) technology, can not only detect distance but also measure object velocity using Doppler frequency shift. Strong atmospheric penetration and high eye safety are significant characteristics of 1550nm laser sources. However, compared to 905nm LiDAR, 1550nm LiDAR still has significant shortcomings in terms of light source and detector cost, size, and supply chain maturity. 1550nm LiDAR generally uses fiber lasers as its light source. Conventional fiber lasers are mostly packaged in a metal shell with round leads, resulting in large size, difficulty in core laser collimation, and low optical power.

[0062] Therefore, this application proposes a packaging shell for a lidar, which encapsulates a lidar with a wavelength of 1550nm, thereby increasing the detection distance while ensuring eye safety. The packaging shell also improves device integration, reduces size, and lowers costs.

[0063] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0064] Figure 1 This is a schematic diagram of the packaging shell of a lidar provided in one embodiment of this application, with reference to... Figure 1 The detailed description of the packaging shell of this lidar is as follows:

[0065] This application provides a lidar enclosure, including: a metal base 100, a metal wall 200, multiple ceramic strips 300, a light window 400, and a shaped sealing ring 500. The metal wall 200 is disposed around the mounting surface of the metal base 100; the ceramic strips 300 are assembled on a first side and a second side of the metal wall 200; the first side and the second side are opposite to each other. The light window 400 is welded to a third side of the metal wall 200 and is composed of a sapphire crystal sheet; the third side is adjacent to the first side. The shaped sealing ring 500 is located above the metal wall 200 and is welded together with the metal wall 200 and the ceramic strips 300.

[0066] For example, Figure 1 and Figure 2 Only an example of setting two ceramic strips 300 on the first side is given. In actual production, one ceramic strip 300 can be set, such as... Figure 3 As shown, there may be two or more ceramic strips 300, so that the package can encapsulate 2n ceramic strips 300, where n is a positive integer.

[0067] Among them, the irregular sealing ring 500 is used to encapsulate the ceramic strip 300.

[0068] For example, the enclosure also includes a fiber optic port 600 for routing and connecting to the ceramic strip 300. The fiber optic port 600 is located on a fourth side of the metal wall 200 opposite the third side.

[0069] Specifically, the first side of the metal wall 200 is provided with a first U-shaped opening. The first U-shaped opening is used to assemble the first ceramic strip 301; the width of the first U-shaped opening is the same as the width of the first ceramic strip 301. The height of the first U-shaped opening is greater than the height of the first ceramic strip 301, and the upper surface of the first ceramic strip 301 is separated from the upper surface of the first U-shaped opening by a first preset distance H1.

[0070] For example, the upper surface of the first ceramic strip 301 is separated from the upper surface of the first U-shaped opening by a first preset distance H1 so that it can be assembled with the irregular sealing ring 500.

[0071] Specifically, the second side of the metal wall 200 is provided with a second U-shaped opening. The second U-shaped opening is symmetrically arranged with the first U-shaped opening; the second U-shaped opening is used to assemble the second ceramic strip 302. The width of the second U-shaped opening is the same as the width of the second ceramic strip 302. The height of the second U-shaped opening is greater than the height of the second ceramic strip 302; the upper surface of the second ceramic strip 302 is a second preset distance H2 from the upper surface of the first U-shaped opening.

[0072] Similarly, the upper surface of the second ceramic strip 302 is at a second preset distance H2 from the upper surface of the first U-shaped opening so that it can be assembled with the irregular sealing ring 500.

[0073] For example, under normal circumstances, the first ceramic strip 301 and the second ceramic strip 302 are completely identical, and the first preset distance H1 and the second preset distance H2 are equal. In special cases, when the dimensions of the first ceramic strip 301 and the second ceramic strip 302 are different, the first preset distance H1 and the second preset distance H2 are different. In this case, the size of the protruding thin sheet of the irregular sealing ring 500 can be modified to accommodate the ceramic strip 300.

[0074] Specifically, the irregularly shaped sealing ring 500 is welded to the upper surface of the metal wall around its perimeter. The first side of the irregularly shaped sealing ring 500 has a raised sheet 501 of a first preset size; the height of the sheet 501 is the same as the height of the first preset distance H1, and it is welded to the first ceramic strip 301. The second side of the irregularly shaped sealing ring 500 has a raised sheet 502 of a second preset size; the height of the sheet 502 is the same as the height of the second preset distance H2, and it is welded to the second ceramic strip 302.

[0075] For example, when the first ceramic strip 301 and the second ceramic strip 302 are exactly the same, the first preset size and the second preset size are the same; when the first ceramic strip 301 and the second ceramic strip 302 are different, the first preset size and the second preset size are different.

[0076] The sealing ring can be irregularly shaped, eliminating the need for an excessively tall sealing ring on the metal wall 200, thus allowing the ceramic strip 300 to be encapsulated. This reduces the height of the ceramic beam, solving the problem of excessive deformation during ceramic production. Furthermore, the irregularly shaped sealing ring can encapsulate ceramic strips of different sizes.

[0077] Specifically, the first side of the metal wall 200 is provided with multiple first U-shaped openings, each of which is spaced a third preset distance apart. The second side of the metal wall 200 is provided with multiple second U-shaped openings, each of which is spaced a fourth preset distance apart.

[0078] For example, the U-shaped openings are spaced apart to separate the ceramic strips 300 during assembly, reducing the impact of welding on the device.

[0079] Specifically, a chamfer is provided at the junction of the thin sheet of the irregular sealing ring 500 and the metal wall 200, such as... Figure 4 As shown by the dashed line.

[0080] For example, the irregular sealing ring 500 has multiple welding surfaces with the wall and ceramic, which can easily lead to weld seams and airtightness failure during high-temperature welding. At the same time, the brazing stress causes the wall to deform, making the welding surface of the light window 400 uneven. After welding, a certain proportion of cracks appear in the light window 400, leading to airtightness failure.

[0081] To address the issue of airtightness failure in the welding of the sealing ring to the wall and ceramics, brazing simulation analysis and DOE test verification revealed that chamfering at the interface between the sealing ring and the wall provides space for the solder to flow, which can ensure the quality of the brazing.

[0082] The size of the chamfer is determined by the size of the welded surface of the tube shell structure.

[0083] For example, to solve the airtightness failure problem at position 400 of the light window caused by brazing deformation, the four corners of the light-transmitting holes on the two walls were changed to semi-circular stress buffer grooves through thermal stress simulation analysis.

[0084] Specifically, the third side of the metal wall 200 is provided with a light-transmitting hole for installing a light window 400, such as... Figure 3 As shown by the dotted lines, semi-circular stress-relief grooves are provided at the four corners of the light-transmitting aperture, such as... Figure 5 As shown.

[0085] The semi-circular stress buffer groove can release brazing stress, reduce the stress on the optical window 400 during welding, solve the cracking problem of the optical window 400, and meet the hermeticity requirements of the packaging.

[0086] As can be seen, the encapsulation shell of this invention, through the cooperation of the metal wall 200 and the irregularly shaped sealing ring 500, can achieve a 2n-piece ceramic component encapsulation structure, improving the integration of the device. The chamfered welding surface of the irregularly shaped sealing ring 500 meets the welding airtightness requirements, improving the airtightness of the device and module. The addition of a semi-circular stress buffer groove to the light-transmitting hole can minimize the stress experienced by the light window 400 during welding, improving the airtightness of the encapsulation. The entire encapsulation shell has high integration, small size, and good airtightness, which can improve inspection efficiency and reduce production costs.

[0087] Secondly, embodiments of this application provide a method for manufacturing a lidar enclosure, comprising: welding a metal wall 200 around the mounting surface of a metal base 100; welding a ceramic strip 300 to a first side and a second side of the metal wall 200; the first side and the second side being opposite to each other; welding a shaped sealing ring 500 above the metal wall 200 and the ceramic strip 300; welding a light window 400 to a third side of the metal wall 200; the light window 400 being made of a sapphire crystal sheet; the third side being adjacent to the first side.

[0088] For example, the metal wall 200 and the irregular sealing ring 500 are prepared by machining.

[0089] Specifically, ceramic strip 300 is made of alumina ceramic material and is prepared using low-temperature co-fired ceramic technology.

[0090] Specifically, the welding methods for welding the metal wall 200 to the metal base 100, welding the ceramic strip 300 to the first and second sides of the metal wall 200, and welding the irregular sealing ring 500 to the top of the metal wall 200 and the ceramic strip 300 are all high-temperature brazing, and the solder is silver-copper material.

[0091] For example, the ceramic strip 300 can be manufactured using the HTCC process, the main processes of which include casting → blanking → punching → filling → printing → lamination → hot cutting → sintering.

[0092] For example, the antireflective coating on the sapphire crystal sheet is fabricated using an evaporation process, and the sapphire crystal sheet is then metallized using a sputtering process. Optical parameters such as the wavelength range and transmittance of the transmitted light through the 400-degree window can be customized as needed.

[0093] For example, the light transmission band of the light window 400 used in the housing can be designed to be 1550±10nm, with a transmittance R≥99.5%.

[0094] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0095] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A packaging shell for a lidar system, characterized in that, include: Metal base, metal walls, multiple ceramic strips, light windows, and irregularly shaped sealing rings; The metal wall is arranged around the mounting surface of the metal base; The ceramic strip is fitted onto the first and second sides of the metal wall; the first side is opposite to the second side. The light window is welded to the third side of the metal wall and is made of a thin sapphire crystal sheet; the third side is adjacent to the first side. The irregularly shaped sealing ring is located above the metal wall and is welded together with the metal wall and the ceramic strip; The first side of the metal wall is provided with a first U-shaped opening; The first U-shaped opening is used to assemble the first ceramic strip; The width of the first U-shaped opening is the same as the width of the first ceramic strip; The height of the first U-shaped opening is greater than the height of the first ceramic strip, and the upper surface of the first ceramic strip is a first preset distance away from the upper surface of the first U-shaped opening.

2. The packaging shell of the lidar as described in claim 1, characterized in that, The second side of the metal wall is provided with a second U-shaped opening; The second U-shaped opening is symmetrically arranged with respect to the first U-shaped opening; The second U-shaped opening is used to assemble the second ceramic strip; The width of the second U-shaped opening is the same as the width of the second ceramic strip; The height of the second U-shaped opening is greater than the height of the second ceramic strip; the upper surface of the second ceramic strip is a second preset distance away from the upper surface of the first U-shaped opening.

3. The packaging shell of the lidar as described in claim 2, characterized in that, The irregularly shaped sealing ring is welded around the upper surface of the metal wall; The first side of the irregular sealing ring is provided with a protruding thin sheet of a first preset size; the height of the thin sheet of the first preset size is the same as the first preset distance, and it is welded to the first ceramic strip; The second side of the irregular sealing ring is provided with a protruding thin sheet of a second preset size; the height of the thin sheet of the second preset size is the same as the second preset distance, and it is welded to the second ceramic strip.

4. The packaging shell of the lidar as described in claim 3, characterized in that, The thin sheet of the irregular sealing ring has a chamfer at the junction with the metal wall.

5. The packaging shell of the lidar as described in claim 1, characterized in that, The first side of the metal wall is provided with a plurality of first U-shaped openings, and each first U-shaped opening is spaced a third preset distance apart; The second side of the metal wall is provided with a plurality of second U-shaped openings, and each second U-shaped opening is spaced a fourth preset distance apart.

6. The packaging shell of the lidar as described in claim 1, characterized in that, The third side of the metal wall is provided with a light-transmitting hole, which is used to install the light window; The four corners of the light-transmitting hole are provided with semi-circular stress buffer grooves.

7. A method for preparing a packaging shell for a lidar, characterized in that, include: The metal wall is welded around the mounting surface of the metal base; Ceramic strips are welded to the first and second sides of the metal wall; the first side and the second side are opposite to each other; wherein, the first side of the metal wall is provided with a first U-shaped opening; the first U-shaped opening is used to assemble the first ceramic strip; the width of the first U-shaped opening is the same as the width of the first ceramic strip; the height of the first U-shaped opening is greater than the height of the first ceramic strip, and the upper surface of the first ceramic strip is a first preset distance away from the upper surface of the first U-shaped opening. The irregularly shaped sealing ring is welded above the metal wall and the ceramic strip; The light window is welded to the third side of the metal wall; the light window is made of a thin sapphire crystal sheet; the third side is adjacent to the first side.

8. The method for preparing the packaging shell of the lidar as described in claim 7, characterized in that, The ceramic strip is made of alumina ceramic material and is prepared using low-temperature co-fired ceramic technology.

9. The method for preparing the packaging shell of the lidar as described in claim 7, characterized in that, The welding methods for welding the metal wall to the metal base, welding the ceramic strip to the first and second sides of the metal wall, and welding the irregular sealing ring to the metal wall and the ceramic strip are all high-temperature brazing, and the solder is silver-copper material.

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