A transceiver module and lidar

Abstract

The application is suitable for the field of automatic driving technology, and provides a transceiving module and a laser radar. The transceiving module comprises a base body, a first medium and a second medium arranged on a first surface of the base body, one of the first medium and the second medium is used for conducting and emitting probe light, and the other is used for receiving and conducting echo light; the first medium and the second medium both extend along a first direction, and are oppositely arranged; a first end of the first medium is oppositely arranged with a second end of the second medium; the first end of the first medium comprises an inclined first reflecting surface, and the second end of the second medium comprises an inclined second reflecting surface. The transceiving module and the laser radar provided by the application have low production cost and high precision.

Description

Technical Field

[0001] This invention belongs to the field of autonomous driving technology, and particularly relates to a transceiver module and a lidar. Background Technology

[0002] A lidar is a radar system that uses laser beams to detect the position, velocity, and other characteristics of a target. Its working principle is to first emit a detection laser beam towards the target, then compare the received signal reflected back from the target with the emitted signal, and after appropriate processing, obtain relevant information about the target, such as the target's distance, azimuth, altitude, velocity, attitude, and even shape.

[0003] However, existing lidar using integrated optics requires the use of free-space optical circulators, which leads to high production costs for lidar. Furthermore, current lidar uses a separate transmit and receive installation method, which causes certain reliability issues in extreme temperature environments in vehicle-mounted scenarios. Summary of the Invention

[0004] The purpose of this invention is to provide a transceiver module and a lidar, aiming to solve the technical problems of high production cost and poor accuracy of lidar in the prior art.

[0005] The present invention is implemented as follows: In a first aspect, a transceiver module is provided, including a substrate, and a first medium and a second medium disposed on a first surface of the substrate, wherein one of the first medium and the second medium is used to receive and emit probe light, and the other is used to receive and transmit echo light.

[0006] Both the first medium and the second medium extend along the first direction and are arranged opposite to each other;

[0007] The first end of the first medium and the second end of the second medium are disposed opposite to each other; the first end of the first medium includes an inclined first reflective surface, and the second end of the second medium includes an inclined second reflective surface.

[0008] In an optional embodiment, multiple first media and multiple second media are provided, with the multiple first media arranged parallel to each other and spaced apart along a second direction perpendicular to the first direction, and the multiple second media arranged parallel to each other and spaced apart along a second direction perpendicular to the second direction.

[0009] In an optional embodiment, the distance between two adjacent first media in the second direction is greater than 20 μm, and the distance between two adjacent second media in the second direction is also greater than 20 μm.

[0010] In an optional embodiment, the centers of the plurality of first reflective surfaces are located on the same straight line;

[0011] Alternatively, at least one of the first reflective surfaces may be misaligned with the other first reflective surfaces.

[0012] In an optional embodiment, the substrate is located on the light-transmitting side of the first medium and the second medium, and the angle between the first reflective surface and the first surface is 30°-60°, and the angle between the second reflective surface and the first surface is also 30°-60°.

[0013] Alternatively, the substrate is located on the back side of the light-transmitting side of the first medium and the second medium, and the angle between the first reflective surface and the first surface is 120°-150°, and the angle between the second reflective surface and the first surface is also 120°-150°.

[0014] In an optional embodiment, the first medium and the second medium have the same height or the difference between their heights is within a preset value, and the nearest distance between the first reflective surface and the second reflective surface is 1 / 10 to 1 / 5 of the height of the first medium or the second medium.

[0015] In an optional embodiment, both the first reflective surface and the second reflective surface are provided with a reflective layer.

[0016] In an optional embodiment, the surface of the first medium, except for the light-transmitting area, is provided with a reflective layer, and the surface of the second medium, except for the light-transmitting area, is also provided with a reflective layer.

[0017] In an optional embodiment, an anti-reflection layer is provided on the surface of the light-transmitting area of ​​the first medium, and an anti-reflection layer is provided on the surface of the light-transmitting area of ​​the second medium.

[0018] In an optional embodiment, the substrate is located on the light-transmitting side of the first medium and the second medium, the substrate is a transparent substrate, and an anti-reflection layer is provided on the light-transmitting areas of the first surface and the second surface opposite to the first surface of the substrate.

[0019] In an optional embodiment, the first medium and the second medium are either waveguides or optical fibers, respectively.

[0020] Secondly, a lidar is provided, including a transmitting module, a receiving module, and a scanning module, and also including the transceiver module provided in the above embodiments. The transmitting module emits a detection light beam, which enters a first medium and is directed towards the scanning module through the first medium. The scanning module deflects the detection light beam and emits it outward for detection. The scanning module is also used to receive echo light and deflect the echo light beam towards the transceiver module. The echo light beam enters a second medium and is directed towards the receiving module through the second medium.

[0021] In an optional embodiment, the scanning module is used to deflect light rays in the X and Y directions, the first direction being parallel to the X direction.

[0022] The technical advantages of this invention compared to the prior art are as follows: In the transceiver module and lidar provided in the embodiments of this invention, the transceiver module includes a substrate and a first medium and a second medium disposed on a first surface of the substrate. One of the first medium and the second medium is used to receive and transmit detection light, and the other is used to receive and transmit echo light. Both the first medium and the second medium extend along a first direction and are disposed opposite to each other. An inclined first reflecting surface is formed at the end of the first medium opposite to the second medium, and an inclined second reflecting surface is formed at the end of the second medium opposite to the first medium. Firstly, the first and second reflecting surfaces can change the propagation direction of the light path, allowing the echo light to be received by the receiving medium in the first and second media even if it is horizontally offset by ≥0.05°. This allows the transceiver module to be assembled without precise displacement, improving its production efficiency and thus enhancing the production efficiency of the lidar. Secondly, the transceiver module can achieve integrated transmission and reception, eliminating the need for a spatial optical circulator, making the transceiver module and lidar structurally compact and reducing production costs. Thirdly, the transceiver module provided in the embodiments of this invention can solve the problem of horizontal reception angle lag, improving the horizontal ranging capability of the lidar. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention or the prior art will be briefly introduced below. 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 effort.

[0024] Figure 1 This is a schematic diagram of the structure of the lidar provided in an embodiment of the present invention;

[0025] Figure 2This is a schematic diagram of the scanning path of the detection light emitted by the lidar used in the embodiment of the present invention. The arrows in the diagram indicate the scanning direction of the detection light.

[0026] Figure 3 This is a schematic diagram of the usage status of a transceiver module provided in an embodiment of the present invention;

[0027] Figure 4 yes Figure 1 A side view of the transceiver module shown.

[0028] Figure 5 yes Figure 1 A schematic diagram of the structure of a single second medium;

[0029] Figure 6 yes Figure 1 A schematic diagram of the structure of a single transceiver unit;

[0030] Figure 7 This is a schematic diagram of the usage status of the transceiver module provided in another embodiment of the present invention;

[0031] Figure 8 yes Figure 7 A three-dimensional structural diagram of the transceiver module shown;

[0032] Figure 9 yes Figure 7 A side view of the transceiver module shown.

[0033] Figure 10 This is a side view of the transceiver module provided in another embodiment of the present invention;

[0034] Figure 11 This is a side view of the transceiver module provided in another embodiment of the present invention;

[0035] Figure 12 This is a three-dimensional structural diagram of a transceiver module provided in another embodiment of the present invention;

[0036] Figure 13 This is a three-dimensional structural diagram of a transceiver module provided in another embodiment of the present invention;

[0037] Figure 14 yes Figure 13 Schematic diagram of the structure at point A;

[0038] Figure 15 This is a schematic diagram of the structure of the frequency-modulated continuous wave lidar used in the embodiments of the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 100. Transceiver module; 110. Substrate; 111. First surface; 112. V-groove; 120. First medium; 121. First reflective surface; 130. Second medium; 131. Second reflective surface; 140. Anti-reflection layer; 200. Transmitting module; 300. Collimating module; 400. Scanning module; 500. Beam splitting module; 600. Receiving module; 700. Signal processing module; A. First direction; B. Second direction; α1. Angle between the first reflective surface and the first surface; α2. Angle between the second reflective surface and the first surface; d. Distance between the closest points of the first reflective surface and the second reflective surface; h. Height of the first medium. Detailed Implementation

[0041] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0042] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0043] 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0044] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0046] In one embodiment of the present invention, a lidar is provided. For example... Figure 1 As shown, the lidar includes a transmitting module 200, a transceiver module 100, a scanning module 400, and a receiving module 600. The transmitting module 200 emits a probe light beam, which is coupled into the transceiver module 100. The transceiver module 100 emits the probe light beam and directs it towards the scanning module 400. After being deflected by the scanning module 400, the probe light beam is directed outward toward the area to be measured. Then, the echo light beam reflected back from an object in the area to be measured is received by the scanning module 400 along a coaxial path. The scanning module 400 deflects the echo light beam and directs it toward the transceiver module 100. The transceiver module 100 receives the echo light beam and directs it toward the receiving module 600. After receiving the echo light beam, the receiving module 600 performs calculations to obtain the detection result. The lidar can be used with either the Time of Flight (ToF) method or the Frequency Modulated Continuous Wave (FMCW) method for ranging.

[0047] Specifically, the transmitting module 200 in this embodiment may include a laser source. The laser source may be a DFB (Distributed Feedback Laser), a VCSEL (Vertical Cavity Surface Emitting Laser), or a DFB+EDFA (Erbium-doped Optical Fiber Amplifier) ​​source. The coupling method between the transmitting module 200, the receiving module 600, and the transceiver module 100 may be fiber optic coupling, microlens coupling, or direct coupling. The receiving module 600 may be a receiving processing chip, a silicon photonics coherent receiver chip, or a combination of a silicon photonics coherent receiver chip and other related structures.

[0048] Please refer to Figure 3 and Figure 7 As shown, the transceiver module 100 in this embodiment includes a substrate 110, and a first medium 120 and a second medium 130 disposed on a first surface 111 of the substrate 110. The first surface 111 mentioned here is generally the upper or lower surface of the substrate 110, but it can also be other surfaces, which can be flexibly selected according to the application requirements.

[0049] Among them, one of the first medium 120 and the second medium 130 is used to receive and emit probe light, and the other is used to receive and transmit echo light.

[0050] It should be noted that the functions of the first medium 120 and the second medium 130 in this embodiment are interchangeable. That is, any medium formed on the substrate 110 can be used to conduct and emit detection light, and also to receive and conduct echo light, depending on the modules connected to each medium and the optical system design of the lidar in actual use. Figure 3 As shown, a medium is provided on the left side of the substrate 110 surface and another medium is provided on the right side; in some embodiments, when in use, the medium on the left is the first medium 120 coupled to the transmitting module 200, and the medium on the right is the second medium 130 coupled to the receiving module 600; in other embodiments, when in use, the medium on the left is the first medium 120 coupled to the receiving module 600, and the medium on the right is the second medium 130 coupled to the transmitting module 200.

[0051] For the sake of brevity, the following description uses the example of the first medium 120 being coupled to the transmitting module 200 for transmitting and emitting the detection light, and the second medium 130 being coupled to the receiving module 600 for receiving and transmitting the echo light, to illustrate the transceiver module 100 and the lidar. It should be noted that the embodiment where the second medium 130 is coupled to the transmitting module 200 for transmitting and emitting the detection light, and the first medium 120 is coupled to the receiving module 600 for receiving and transmitting the echo light, differs from the above example only in that the light transmitted in the first medium 120 and the second medium 130 are interchanged.

[0052] Thus, the specific optical path for detection using the lidar provided in this embodiment is as follows: the transmitting module 200 emits a detection beam, which enters the first medium 120 and is directed to the scanning module 400 through the first medium 120. The scanning module 400 deflects the detection beam and emits it outward for detection. The scanning module 400 is also used to receive the echo beam and deflects the echo beam and directs it to the transceiver module 100. The echo beam enters the second medium 130 and is directed to the receiving module 600 through the second medium 130.

[0053] The first medium 120 and the second medium 130 both extend along a first direction A, and are arranged opposite to each other. Specifically, the first direction A can be the length or width direction of the substrate 110, or other directions, which can be flexibly selected according to the application requirements. The first medium 120 and the second medium 130 being arranged opposite to each other means that the first end of the corresponding first medium 120 and the second end of the corresponding second medium 130 are arranged opposite to each other. The distance between the first end of the first medium 120 and the second end of the second medium 130 can be determined according to the receiving effect of the second medium 130 on the echo light. As long as the receiving rate of the echo light received by the second medium 130 after the detection light emitted by the first medium 120 is reflected by the target object can meet the detection requirements, it is acceptable.

[0054] The first end of the first medium 120 includes an inclined first reflective surface, and the second end of the second medium 130 includes an inclined second reflective surface.

[0055] Specifically, when the first medium 120 is used as the emitting medium, the light-emitting end of the first medium 120 includes an inclined first reflective surface 121. The first reflective surface 121 is used to reflect the probe light, and the emission direction of the probe light forms an angle with the first surface 111. This angle can be 90°, an acute angle with the first surface 111, or an obtuse angle with the first surface 111; the specific angle can be designed according to the light emission requirements. At this time, the second medium 130 is used as the receiving medium. The second reflective surface 131 is formed at the light-incident end of the second medium 130 to receive and reflect the echo light, so that the echo light enters the main body of the second medium 130. The main body of the second medium 130 refers to the portion of the second medium 130 excluding the light-incident end. The incident direction of the aforementioned echo light is parallel or approximately parallel to the exit direction of the aforementioned detection light emitted from the first medium 120. Therefore, the echo light is set at an angle to the first surface 111. After passing through the second reflecting surface 131, its propagation direction changes and it can propagate within the second medium 130.

[0056] When the first medium 120 is used as a receiving medium, the aforementioned first reflective surface 121 is formed at the light-incident end of the first medium 120 to receive and reflect the echo light, so that the echo light enters the main body of the first medium 120. Here, the main body of the first medium 120 refers to the portion of the first medium 120 excluding the light-incident end. In this case, the second medium 130 is used as a transmitting medium, and the second reflective surface 131 is formed at the light-outceasing end of the second medium 130 to reflect the probe light, so that the emission direction of the probe light forms an angle with the first surface 111.

[0057] In this embodiment, the substrate 110 can be located on the light-transmitting side (i.e., the light-emitting side of the probe light and / or the light-incident side of the echo light) of the first medium 120 and the second medium 130. That is, the probe light is reflected by the first reflecting surface 121 of the first medium 120 and then emitted outwards, passing through the substrate 110 before being emitted outwards. Simultaneously, the echo light needs to pass through the substrate 110 to couple into the second medium 130. Alternatively, it can be located on the back side of the light-transmitting side of the first medium 120 and the second medium 130. That is, the probe light, after being reflected by the first reflecting surface 121 of the first medium 120, is emitted directly outwards without passing through the substrate 110, while the echo light can directly couple into the second medium 130 without passing through the substrate 110. The specific location can be flexibly selected according to the application requirements.

[0058] It should be noted that in this embodiment, the distance between the corresponding first medium 120 and second medium 130 in the transceiver module 100 is the same as the spot offset caused by the optical hysteresis angle caused by the scanning module 400, or the difference between the two is within a preset range, so as to ensure that the second medium 130 can receive enough echo light.

[0059] When using the lidar provided in this embodiment for detection, the lidar rapidly scans the field of view by deflecting the optical path through the scanning module 400 to achieve long-range detection of the target. Because the photons travel a longer distance during long-range detection, the spatial orientation of the scanning module 400 when receiving the echo light has changed significantly compared to when the detection light was emitted, resulting in a lidar scanning reception angle lag effect. This lidar scanning reception angle lag effect manifests in both the horizontal and vertical directions.

[0060] However, in a lidar system, as described earlier regarding the scanning module 400, such as... Figure 2 As shown, the scanning module deflects light rays in the X and Y directions, enabling the lidar to scan in these directions. During scanning, the scanning angle range in the vertical direction (Y direction) is generally smaller than that in the horizontal direction (X direction), resulting in a significantly lower angular lag effect in the vertical direction compared to the horizontal direction. Furthermore, a scanning module 400 moving at a low speed in the vertical direction can be used to further reduce the angular lag effect in the vertical direction. Thus, the lidar system design can primarily consider the angular lag effect in the horizontal direction.

[0061] In this embodiment, the corresponding first medium 120 and second medium 130 extend in the same direction and are arranged opposite to each other. At the same time, the end of the first medium 120 near the second medium 130 forms an inclined first reflective surface 121, and the end of the second medium 130 near the first medium 120 forms an inclined second reflective surface 131. Thus, the transceiver module 100 provided in this embodiment of the invention can change the propagation direction of the detection light that originally propagated parallel to the first surface 111 to be perpendicular to the first surface 111 or at other angles with the first surface 111. It can also make the echo light that is perpendicular to the first surface 111 or at other angles with the first surface 111 be received by the medium in the first medium 120 and the second medium 130 used to receive the echo light.

[0062] Furthermore, in this embodiment, the first medium 120 can change the direction of the detection light rays that were originally parallel to the first surface 111 of the substrate 110 to be perpendicular to the first surface 111 or at other angles to the first surface 111. For transceiver units with the same direction of light transmission, transmission and reception can only be designed in one dimension. Precise displacement is required during the production of multiple transceiver units, resulting in low production efficiency of the transceiver module 100. However, with the transceiver module 100 provided in this embodiment, even if multiple first media 120 and second media 130 are provided, the multiple first media 120 and second media 130 can operate independently or with minimal impact, thereby effectively improving the production efficiency of the transceiver module 100. Simultaneously, the lidar provided in this embodiment does not require a free-space optical circulator, reducing hardware overhead, lowering costs, simplifying the system, reducing the complexity of the optomechanical system, minimizing the overall system size, and weakening the preamble signal, thus improving reliability.

[0063] Therefore, the lidar provided by the embodiments of the present invention can effectively improve the echo light reception rate in the horizontal direction, thereby effectively reducing the adverse effects of the horizontal reception angle lag effect on detection and improving detection accuracy. At the same time, the lidar provided by the embodiments of the present invention has high reliability, low production cost, and high production efficiency.

[0064] In the above embodiments, one or more of the first medium 120 and the second medium 130 can be provided. However, when both the first medium 120 and the second medium 130 are provided, multiple transceiver modules arranged in an array are often required in a single lidar to meet the detection requirements, resulting in low assembly efficiency. To solve this problem, in an optional embodiment, such as... Figure 8 As shown, there are multiple first media 120 and multiple second media 130. The multiple first media 120 are parallel to each other and arranged at intervals along a second direction B that is perpendicular to the first direction A. The multiple second media 130 are parallel to each other and arranged at intervals along the second direction B.

[0065] Specifically, any corresponding first medium 120 and second medium 130 can form a transceiver unit. In this embodiment, multiple first mediums 120 and second mediums 130 are provided, meaning they can form a transceiver unit array on the same plane. Thus, a single LiDAR module can meet its detection needs, effectively improving assembly efficiency and reducing production costs. Furthermore, compared to using only one first medium 120 and one second medium 130 in the transceiver unit, the number of transceiver channels arranged horizontally can be increased, improving the horizontal resolution of the LiDAR. Additionally, this configuration allows for the selection of the first medium to be connected or the number to be set according to the required transmission field of view, thereby adjusting the transmission field of view and meeting the needs of customers in different scenarios.

[0066] Optionally, a transceiver unit may also include a first medium 120 and multiple second media 130, thereby improving reception efficiency.

[0067] Furthermore, when the second direction is consistent with the vertical direction, and the Y-direction scan of the scanning module is also consistent with the vertical direction, the echo light that has shifted due to the reception angle lag effect in the vertical direction can still be received by the adjacent second medium 130, thereby improving the light reception rate of the transceiver module 100 in the vertical direction and improving the ranging capability of the lidar. In addition, the transceiver module arranges multiple pairs of transceiver units in the vertical direction, increasing the number of transceiver channels arranged in the vertical direction and improving the resolution of the lidar in the vertical direction.

[0068] In the above embodiments, different transceiver units can be arranged at arbitrary intervals along the first direction A and the second direction B. The interval along the first direction A refers to the interval between custom positions of different transceiver units along the first direction A. These positions can be manually set as needed, and can be the light inlet of the first medium, the top or bottom of the first reflective surface, the top or bottom of the second reflective surface, or other positions; no single limitation is made here. The edges of the first and second media can be set as a periodic array to facilitate coupling.

[0069] In one exemplary embodiment, multiple first media are arranged at equal intervals in a first direction A and a second direction B, with a spacing of 100 μm in the first direction A and a spacing of 50 μm in the second direction B. This structure offers high light reception and is easy to fabricate.

[0070] In one specific embodiment, the transceiver module is provided with 8 transceiver units, and the spacing between two adjacent transceiver units is 120μm. When in use, if the focal length of the collimation module used by the lidar is 35mm, the angle of the echo light received by two adjacent second media in the X direction can be staggered by 0.2°.

[0071] To ensure effective reception while avoiding material waste, in an optional embodiment, the distance between two adjacent first media in the second direction is greater than 20 μm. The distance between two adjacent second media in the second direction is also greater than 20 μm.

[0072] In the above embodiments, as Figure 8 and Figure 12 As shown, when there are multiple first mediums 120 and second mediums 130, that is, when the transceiver module has multiple transceiver units, the gaps between the first mediums 120 and second mediums 130 in all transceiver units can be set on a straight line or not on a straight line. That is, each first reflective surface can be placed arbitrarily in the horizontal and vertical directions, and the array period can also be set arbitrarily. Specifically, it can be set according to the reception effect.

[0073] In an optional embodiment, such as Figure 8 As shown, the centers of the multiple first reflecting surfaces are located on the same straight line. Specifically, this straight line can be a straight line extending along the second direction B, or a straight line forming an angle with the second direction B, which can be flexibly set according to the detection requirements.

[0074] In another alternative embodiment, such as Figure 12 As shown, at least one first reflecting surface is offset from the other first reflecting surfaces, which can be flexibly set according to the detection requirements. Using this structure, the horizontal resolution of the lidar can be improved while still allowing the aforementioned scanning module to perform its scanning function.

[0075] In an optional embodiment, such as Figure 7 and Figure 9 As shown, the substrate 110 is located on the light-transmitting side of the first medium 120 and the second medium 130. The angle α1 between the first reflective surface 121 and the first surface 111 is any angle between 30° and 60°, and the angle α2 between the second reflective surface 131 and the first surface 111 is any angle between 30° and 60°. The light-transmitting side mentioned here includes both the light-incident side and the light-exit side of the medium.

[0076] In another alternative embodiment, such as Figure 3 and Figure 4As shown, the substrate 110 is located on the back side of the light-transmitting side of the first medium 120 and the second medium 130. The angle α1 between the first reflective surface 121 and the first surface 111 is any angle between 120° and 150°, and the angle α2 between the second reflective surface 131 and the first surface 111 is any angle between 120° and 150°.

[0077] The angles used for the first reflecting surface 121 and the second reflecting surface 131 described above can meet general detection requirements. The specific angle used can be set according to the detection requirements and actual detection effects of different lidars, and is not limited here. The tilt angles of the first reflecting surface 121 and the second reflecting surface 131 can be the same or different, and can be set according to the detection requirements and actual detection effects to ensure that the propagation directions of the detection light and the echo light are basically consistent, making the transmission and reception coaxial and compatible with the scanning module.

[0078] In a specific embodiment, such as Figure 9 As shown, the substrate 110 is located on the light-emitting side of the first medium 120, and the angles between the first reflecting surface 121 and the second reflecting surface and the first surface are both 45°. In another specific embodiment, as... Figure 4 As shown, the substrate 110 is located on the back side of the light-emitting side of the first medium 120, and the angles between the first reflective surface 121 and the second reflective surface and the first surface are 135°.

[0079] To ensure effective reception while avoiding material waste, in one optional embodiment, such as Figure 6 As shown, the first medium 120 and the second medium 130 have the same height or the difference between their heights is within a preset value. The closest distance d between the first reflective surface 121 and the second reflective surface 131 is 1 / 10 to 1 / 5 of the height h of the first medium 120 or the second medium 130. Since both the first reflective surface 121 and the second reflective surface 131 are inclined surfaces, the gap between them is a trapezoidal space with a gradually changing longitudinal cross-sectional area. The minimum distance mentioned here is the length of the shortest part of this trapezoidal space. Using the configuration of this embodiment, the transceiver module can receive most of the echo light, has good detection accuracy, and requires less medium material.

[0080] In an optional embodiment, both the first and second reflective surfaces are provided with reflective layers to ensure good reflection effect.

[0081] In an optional embodiment, the surface of the first medium, except for the light-transmitting area, is provided with a reflective layer, and the surface of the second medium, except for the light-transmitting area, is also provided with a reflective layer, so as to reduce outward diffusion and loss when light is transmitted in each medium.

[0082] To reduce light energy loss and further improve the ranging capability of the lidar using the transceiver module 100 provided in the above embodiments, in an optional embodiment, such as Figure 10 As shown, an anti-reflection layer is provided on the surface of the light-transmitting area of ​​the first medium 120, and an anti-reflection layer is provided on the surface of the light-transmitting area of ​​the second medium 130. The anti-reflection layer can effectively reduce the probability of emission and reflection when the probe light or echo light passes through the surface of the light-transmitting area of ​​the first medium 120 or the surface of the light-transmitting area of ​​the second medium 130, thereby increasing the amount of probe light emitted and the amount of echo light received, so that the lidar receives more echo light, thereby improving the ranging capability of the lidar using the transceiver module 100 provided in the above embodiments.

[0083] In an optional embodiment, such as Figure 11 As shown, the substrate 110 is located on the light-transmitting side of the first medium 120 and the second medium 130, that is, the light-emitting side of the probe light and the light-incident side of the echo light. The substrate 110 is a transparent substrate, and an anti-reflection layer 140 is provided on the light-transmitting areas of both the first surface 111 and the second surface opposite to the first surface 111. The light-transmitting area referred to here refers to all areas in the first surface 111 and the second surface that can be passed through by the probe light and / or the echo light, including the area of ​​the first surface 111 other than the area covered by the first medium 120, and the entire area of ​​the second surface.

[0084] At this time, the light output from the first medium 120 needs to pass through the substrate 110 before it can be output by the transceiver module 100, and the echo light also needs to pass through the substrate 110 before entering the second medium 130. The substrate 110 is a transparent substrate to ensure that the detection light and the echo light can pass through smoothly. The anti-reflection layer 140 can further improve the light transmittance, the output rate of the detection light, and the reception rate of the echo light, thereby improving the ranging capability of the lidar using the transceiver module 100 provided in the above embodiments.

[0085] In an optional embodiment, the first surface 111 of the transparent substrate has an incident light region, an emitted light region, and a coated region. The coated region is the area of ​​the first surface 111 excluding the incident light region and the emitted light region. A total reflection film is formed on the coated region. The probe light output from the first medium 120 can enter the transparent substrate through the incident light region, and the echo light can enter the second medium 130 from the transparent substrate through the emitted light region. An antireflection layer 140 is formed on the surface of the transparent substrate other than the first surface 111. The transceiver module 100 provided in this embodiment facilitates coating and fabrication.

[0086] In the above embodiments, the first medium and the second medium are either a waveguide or an optical fiber, respectively. There are four main representations:

[0087] In the first type, both the first and second dielectrics are waveguides, such as... Figures 3 to 12 As shown;

[0088] The second type involves both the first and second media being optical fibers, such as... Figure 13 and Figure 14 As shown;

[0089] The third type uses a waveguide as the first medium and an optical fiber as the second medium.

[0090] The fourth type uses optical fiber as the first medium and waveguide as the second medium.

[0091] More specifically, when both the first and second media are waveguides, the transceiver module is a planar waveguide chip with a substrate as the base. During fabrication, a bevel can be formed at the end of the transmitting waveguide near the receiving waveguide. Then, a total reflection waveguide film / layer, or a reflective film, can be deposited on this bevel to form the first reflecting surface. Alternatively, a total reflection waveguide film / layer, or a reflective film, can be deposited on all areas of the outer surface of the transmitting waveguide except for the light-incident and light-excising regions, or a reflective film can be attached. Similarly, the second reflecting surface in the receiving waveguide can also be manufactured in the same way. However, it should be noted that the second reflecting surface and the first reflecting surface must be positioned opposite each other. The two surfaces can be fabricated simultaneously or separately. Furthermore, a total reflection waveguide film, or a reflective film, can also be deposited on all areas of the outer surface of the receiving waveguide except for the light-incident and light-excising regions.

[0092] In this embodiment, the first and second media can be waveguides. The waveguide used for transmission can be a single-mode waveguide, and the waveguide used for reception can be a single-mode or multi-mode waveguide. The waveguide material can be SiO2, an organic polymer, or silicon. Furthermore, the transmitting and receiving waveguides can each have a uniform cross-section structure, or they can employ a single-mode to large-mode or large-mode to single-mode structure. During manufacturing, the organic polymer can be directly imprinted onto the substrate of the laser wavelength to be used using a nanoimprinting process. Then, the corresponding surfaces of the transmitting and receiving waveguides are coated to form the first and second reflecting surfaces. Alternatively, the transmitting and receiving waveguides can be prepared first and then assembled onto a substrate using precision assembly. Of course, in other embodiments, the transmitting and receiving waveguides can also be fabricated using etching, machining, or other methods; this is not a limiting factor.

[0093] The transceiver module adopts the above-mentioned first medium and second medium in a relative arrangement, which not only improves the detection accuracy, reliability and production efficiency of the corresponding lidar, but also effectively eliminates the problem that the one-dimensional waveguide array of the planar waveguide chip cannot arbitrarily deflect light in the vertical direction.

[0094] Furthermore, when the transceiver module has multiple first and second media, compared to the design method of setting multiple sets of transmitting and receiving waveguides on the planar waveguide chip by vertical stacking to improve the echo light reception rate in the vertical direction, the transceiver module setting method provided in this embodiment of the invention does not require thinning, precise alignment, or other operations on the PLC (planar lightwave circuit) wafer, thereby effectively reducing the production cost of the transceiver module and improving production efficiency.

[0095] When either the first or second medium is an optical fiber, the substrate can consist of two parts: one part supports or fixes the first medium, and the other part supports or fixes the second medium. The substrate used to fix the optical fiber can be a glass substrate with a V-groove formed on its first surface. The optical fiber is then fixed to the V-groove by bonding or other methods. Specifically, as shown... Figure 13 As shown. Optical fibers can be single-mode fibers, multimode fibers, large-mode-field fibers, and can also be single-mode to multimode fibers or multimode to single-mode fibers, depending on the specific application requirements. An optical fiber has a core and an insulating portion surrounding and coaxially positioned around the core. In use, the insulating portion at the end of the fiber opposite to the other medium can be removed to expose the core. Then, a bevel is machined on the end face of the core to form a first or second reflecting surface, allowing the probe light or echo light to exit or enter the fiber through the extended portion, such as... Figure 13 and Figure 14 As shown.

[0096] In an optional embodiment, the scanning module 400 is used to deflect light rays in the X and Y directions. The first direction A is parallel to the X direction.

[0097] The X and Y directions mentioned here refer to the horizontal and vertical directions when the LiDAR is placed upright. In actual use, the X and Y directions will shift due to different placement methods of the LiDAR. It should be understood that when the LiDAR is not placed upright, the X and Y directions will also change and will no longer be horizontal and vertical.

[0098] In a specific embodiment, such as Figure 15 As shown, the lidar is a frequency-modulated continuous wave lidar. The frequency-modulated continuous wave lidar includes a transmitting module 200, a beam splitting module 500, a transceiver module 100, a collimation module 300, a scanning module 400, a receiving module 600, and a signal processing module 700. The signal processing module 700 includes a signal adjustment circuit, a signal acquisition and processing circuit, a control algorithm module, and an external interface.

[0099] The process of detecting the target object is as follows: The transmitting module 200 emits a detection beam, which is first split into two beams by the beam splitting module 500. One beam is used as the local oscillator beam and enters the receiving module 600, while the other beam enters the first medium 120 and is used as the detection beam. The detection beam is then coupled into the first medium 120, and after being conducted through the first medium 120, it reaches the first reflecting surface 121. After being reflected by the first reflecting surface 121, it exits the first medium 120. The detection beam is then collimated by the collimating module 300 and then scanned by the scanning module 400 to form a scanning beam that illuminates the target object. The beam is then reflected back by the target object as an echo beam. The coaxial echo beam is coupled into the second medium 130 through the scanning module 400 and the collimating module 300, and then output to the receiving module 600 through the second medium 130. The echo light entering the receiving module 600 can coherently beat the local oscillator light in the receiving module 600 to generate a beat frequency coherent signal. Then, the photodetector in the receiving module 600 can receive and process the beat frequency coherent signal, and then transmit the data signal to the external signal processing module 700. The signal processing module 700 analyzes the data signal to obtain detection data such as the distance and speed of the target object.

[0100] In a specific embodiment, such as Figure 15 As shown, the transmitting module 200 includes a laser source, which adopts the form of DFB+EDFA and is coupled into the transceiver module 100 through one or more optical fibers. Each first medium in the transceiver module 100 is coupled to one optical fiber. There are a total of N (N≥1) paths in the first medium, and the optical power of each path in the first medium is equal. Correspondingly, there are also N paths in the second medium. The beam splitter module 500 is used to split the light split from the transmitting module 200 into N+M paths, where N paths are output to the transceiver module 100 for transmission, and M paths are output to the receiving module 600 as local oscillator light. The receiving module 600 includes a silicon photonic coherent receiver chip.

[0101] Before the DFB laser output reaches the EDFA optical amplifier, it is first split into M low-power optical fibers to act as local oscillator light and coupled into the silicon photonic coherent receiver chip. The detectors in the silicon photonic coherent receiver chip can perform polarization diversity or not. The silicon photonic coherent receiver chip has balanced detector units, each corresponding to a transimpedance amplifier (TIA). The TIA is part of the signal conditioning circuit, which converts the current signal output from the balanced photoelectric detector (BPD) in the balanced detector unit into a voltage signal, amplifies it a second time, and transmits it to the signal acquisition and processing circuit. The signal conditioning circuit also acquires the local oscillator beat frequency signal from the MZI delay path for closed-loop nonlinear correction of the DFB laser. The control and processing algorithm module processes the acquired raw data, calculating information such as the distance, velocity, direction, and reflectivity of the current target object. In addition, the aforementioned frequency-modulated continuous wave lidar also includes a power management module, which mainly supplies power to the above circuit modules to ensure their normal operation.

[0102] In the above embodiments, a certain installation tolerance is allowed between the first medium and the second medium. Specifically, they can be offset by 1 / 20 of the collimation module's focal length in the depth-of-field direction (i.e., the second direction).

[0103] The above are merely preferred embodiments of the present invention, and only specifically describe the technical principles of the present invention. These descriptions are only for explaining the principles of the present invention and should not be construed as limiting the scope of protection of the present invention in any way. Based on this explanation, any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention, as well as other specific embodiments of the present invention that can be conceived by those skilled in the art without creative effort, should be included within the scope of protection of the present invention.

Claims

1. A transceiver module, characterized by It includes a substrate, and a first medium and a second medium disposed on a first surface of the substrate, wherein one of the first medium and the second medium is used to conduct and emit probe light, and the other is used to receive and conduct echo light. Both the first medium and the second medium extend along the first direction and are arranged opposite to each other; The first end of the first medium and the second end of the second medium are disposed opposite to each other; the first end of the first medium includes an inclined first reflective surface, and the second end of the second medium includes an inclined second reflective surface.

2. The transceiver module of claim 1, wherein, The first medium and the second medium are provided in multiples, the multiple first mediums are arranged parallel to each other and spaced apart along a second direction perpendicular to the first direction, and the multiple second mediums are arranged parallel to each other and spaced apart along the second direction.

3. The transceiver module as described in claim 2, characterized in that, The distance between two adjacent first media in the second direction is greater than 20 μm, and the distance between two adjacent second media in the second direction is also greater than 20 μm.

4. The transceiver module as described in claim 2, characterized in that, The centers of the multiple first reflective surfaces are located on the same straight line; Alternatively, at least one of the first reflective surfaces may be misaligned with the other first reflective surfaces.

5. The transceiver module as described in claim 1, characterized in that, The substrate is located on the light-transmitting side of the first medium and the second medium, and the angle between the first reflective surface and the first surface is 30°-60°, and the angle between the second reflective surface and the first surface is also 30°-60°. Alternatively, the substrate is located on the back side of the light-transmitting side of the first medium and the second medium, and the angle between the first reflective surface and the first surface is 120°-150°, and the angle between the second reflective surface and the first surface is also 120°-150°.

6. The transceiver module as described in claim 1, characterized in that, The first medium and the second medium have the same height or the difference between their heights is within a preset value, and the closest distance between the first reflective surface and the second reflective surface is 1 / 10 to 1 / 5 of the height of the first medium or the second medium.

7. The transceiver module as described in claim 1, characterized in that, Both the first reflective surface and the second reflective surface are provided with a reflective layer.

8. The transceiver module as described in claim 7, characterized in that, The first medium has a reflective layer on all surfaces except the light-transmitting area, and the second medium also has a reflective layer on all surfaces except the light-transmitting area.

9. The transceiver module as described in claim 1, characterized in that, An anti-reflection layer is provided on the surface of the light-transmitting area of ​​the first medium, and an anti-reflection layer is provided on the surface of the light-transmitting area of ​​the second medium.

10. The transceiver module as described in claim 1, characterized in that, The substrate is located on the light-transmitting side of the first medium and the second medium. The substrate is a transparent substrate, and an anti-reflective layer is provided on the light-transmitting areas of the first surface and the second surface opposite to the first surface of the substrate.

11. The transceiver module as described in any one of claims 1-10, characterized in that, The first medium and the second medium are either waveguides or optical fibers, respectively.

12. A lidar, characterized in that, The device includes a transmitting module, a receiving module, and a scanning module, and further includes a transceiver module as described in any one of claims 1-11. The transmitting module emits a probe light, which enters the first medium and passes through the first medium to the scanning module. The scanning module deflects the probe light and emits it outward for detection. The scanning module is also used to receive an echo light and deflect the echo light to the transceiver module. The echo light enters the second medium and passes through the second medium to the receiving module.

13. The lidar as described in claim 12, characterized in that, The scanning module is used to deflect light rays in the X and Y directions, with the first direction being parallel to the X direction.

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