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 the base body, and the first medium and the second medium are arranged correspondingly, the extension directions of the corresponding first medium and the second medium form a preset included angle, one of the first end of the first medium and the second end of the second medium is used for emitting a detection light, and the other end is used for coupling in a return light, at least one of the first end and the second end comprises an inclined reflecting surface, and the reflecting surface is used for deflecting the light; the extension directions of the first medium and the second medium are perpendicular to each other, the first medium is arranged on the first surface of the base body, and the first end comprises the 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. 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 reliability 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 the substrate. The first medium and the second medium are disposed correspondingly, and the extension directions of the corresponding first medium and the second medium form a preset angle. One end of the first medium and the second medium is used to emit a probe light, and the other end is used to couple an echo light. At least one of the first end and the second end includes an inclined reflective surface, which is used to deflect the light.

[0006] In an optional embodiment, the first medium and the second medium extend in directions perpendicular to each other, the first medium is disposed on a first surface of the substrate, and the first end includes the reflective surface.

[0007] In an optional embodiment, in the two corresponding media, at least half of the incident light region of the second medium on the first surface is located outside the second projection region of the first medium on the first surface, and when the entire first projection region is located outside the second projection region, the distance between the first projection region and the second projection region is less than or equal to twice the width of the projection region of the medium used to receive and transmit the echo signal on the first surface.

[0008] In an optional embodiment, there are multiple first media and multiple second media, with the multiple first media arranged in parallel and spaced apart, and the multiple second media arranged in parallel and spaced apart.

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

[0010] In an optional embodiment, the angle between the reflective surface and the extending direction of the first medium is 30°-60°.

[0011] In an optional embodiment, the first medium is either a waveguide or an optical fiber, and the second medium is also either a waveguide or an optical fiber.

[0012] In an optional embodiment, the substrate includes a first part and a second part, wherein the first part is used to fix the first medium and the second part is used to fix the second medium.

[0013] In an optional embodiment, when the first medium is an optical fiber, the first split body has a V-groove for accommodating the first medium; when the second medium is an optical fiber, the second split body has a V-groove for accommodating the second medium.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] In an optional embodiment, the scanning module is used to deflect light rays in the X and Y directions.

[0018] 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 extended regions of the corresponding first medium and second medium have overlapping regions, or the projected regions on the same plane have overlapping regions, the first end of the first medium and the second end of the second medium are arranged opposite to each other, and at least one of the first end and the second end includes an inclined reflective surface. Firstly, the corresponding first and second media are used to transmit the detection light and the echo light. This transceiver module design allows for precise positioning during production, eliminating the need for assembly through precise displacement, thus improving production efficiency and consequently, the production efficiency of the lidar. The corresponding first and second media are used to transmit the detection light and the echo light, respectively, and a reasonable spacing between the first and second media along the hysteresis direction solves the problem of reception hysteresis. Secondly, the transceiver module provided in this embodiment can achieve integrated transceiver operation, eliminating the need for a spatial optical circulator, resulting in a compact structure for both the transceiver module and the lidar, and reducing production costs. Thirdly, the transceiver module provided in this embodiment allows for optical path deflection via a reflective surface, preventing the transceiver module's optical path from being parallel to the substrate. Vertically arranging the transceiver module enables the stacking of the transceiver units composed of the first and second media in the vertical direction, effectively improving the lidar's resolution in the vertical direction and enhancing its detection accuracy. Attached Figure Description

[0019] 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.

[0020] Figure 1 This is a schematic diagram of the structure of the lidar provided in an embodiment of the present invention;

[0021] Figure 2 This 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.

[0022] Figure 3 This is a schematic diagram of the usage status of a transceiver module provided in an embodiment of the present invention;

[0023] Figure 4 yes Figure 3 A top view of the transceiver module shown.

[0024] Figure 5 yes Figure 3 A three-dimensional structural diagram of the transceiver module shown;

[0025] Figure 6 yes Figure 5 A magnified view of a portion of point A in the middle;

[0026] Figure 7 This is a schematic diagram of the transceiver module provided in another embodiment of the present invention;

[0027] Figure 8 This is a schematic diagram of the usage status of the transceiver module provided in another embodiment of the present invention;

[0028] Figure 9 This is a schematic diagram of the usage status of the transceiver module provided in another embodiment of the present invention;

[0029] Figure 10 This is a schematic diagram of the structure of the frequency-modulated continuous wave lidar used in the embodiments of the present invention.

[0030] Explanation of reference numerals in the attached figures:

[0031] 100. Transceiver module; 110. Substrate; 111. V-groove; 120. First medium; 121. Reflective surface; 122. Core; 123. Insulating part; 130. Second medium; 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; C. Third direction; α. Angle between the reflecting surface and the extension direction of the first medium; a. Spacing between the first projection area and the second projection area; b. Width of the incident surface of the second medium. Detailed Implementation

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] Please refer to Figure 1 As shown, in one embodiment of the present invention, a lidar is provided. 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 applied to the Time of Flight (ToF) method or the Frequency Modulated Continuous Wave (FMCW) method.

[0038] 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.

[0039] Please refer to Figure 3 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 the substrate 110. One of the first medium 120 and the second medium 130 is used to conduct and transmit probe light, and the other is used to receive and conduct echo light.

[0040] In this embodiment, the first medium 120 and the second medium 130 can be either waveguides or optical fibers, with at least one of each type provided, and the number of each type is equal. The substrate 110 in this embodiment can be a single unit or composed of two parts, depending on the material and fabrication method of the first medium 120 and the second medium 130. For example, when both the first medium 120 and the second medium 130 are waveguides, the substrate 110 can be a single substrate. Figure 8 As shown, the first medium 120 and the second medium 130 are respectively fabricated on two adjacent surfaces of the substrate 110; alternatively, as shown... Figure 9 As shown, two substrates are used. A first dielectric 120 is fabricated on one substrate, and a second dielectric 130 is fabricated on the other substrate. The two dielectrics are then assembled into a transceiver module through precision assembly. When both the first dielectric 120 and the second dielectric 130 are optical fibers, the substrate 110 can be a glass carrier, with the first dielectric 120 and the second dielectric 130 fabricated on two adjacent surfaces of the substrate 110; alternatively, as shown... Figure 3 As shown, two glass carriers are used. The first medium 120 is fabricated on one glass carrier, and the second medium 130 is fabricated on the other glass carrier. The two sets of media are then assembled into a transceiver module through precision assembly. When the first medium 120 and the second medium 130 are made of different materials, the substrate 110 can be composed of two separate parts made of different materials to adapt to the first medium 120 and the second medium 130 with different materials.

[0041] It should be noted that the functions of the first medium 120 and the second medium 130 in this embodiment are interchangeable. That is, either medium formed on the substrate 110 can be used to conduct both the probe light and the echo light, depending on the device connected to each medium in actual use. Specifically, when the first medium 120 is coupled to the transmitting module 200 and the second medium 130 is coupled to the receiving module 600, the first medium 120 is the transmitting medium for receiving and conducting the probe light, and the second medium 130 is the receiving medium for receiving and conducting the echo signal. If the first medium 120 is coupled to the receiving module 600 and the second medium 130 is coupled to the transmitting module 200, the second medium 130 is the transmitting medium for receiving and conducting the probe light, and the first medium 120 is the receiving medium for receiving and conducting the echo signal.

[0042] 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.

[0043] 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 couples into the first medium 120 and exits through the first medium 120 before being directed toward the scanning module 400. The scanning module 400 deflects the detection beam and then emits it outward for detection. The scanning module 400 is also used to receive the echo beam and deflects it before coaxially directing it toward the transceiver module 100. The echo beam enters the second medium 130 and then enters the receiving module 600 through the second medium 130.

[0044] 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.

[0045] In this embodiment, the first medium 120 and the second medium 130 are correspondingly arranged, and the extension directions of the corresponding first medium 120 and the second medium 130 form a preset angle. This preset angle can be any angle between 150° and 180°, or any angle between 60° and 120°. That is, the corresponding first medium 120 and the second medium 130 can be arranged in multiple ways. One arrangement is that the first medium 120 and the second medium 130 are arranged opposite each other, with their extension directions forming a 180° angle; another arrangement is that the first medium 120 and the second medium 130 are arranged perpendicularly, with their extension directions forming a 90° angle. In other embodiments, the extension directions of the first medium 120 and the second medium 130 can also use other angles, such as 60°, 75°, 110°, etc., as long as one medium can be used to emit detection light and the other can receive echo light.

[0046] The first end of the first medium 120 and the second end of the second medium 130 are respectively provided. Specifically, one end of the first end of the first medium 120 and the second end of the second medium 130 is used to emit a probe light, and the other end is used to couple in an echo light. At least one of the first end and the second end includes an inclined reflective surface 121, which is used to deflect the light and can be either a probe light or an echo light.

[0047] Specifically, when the reflective surface 121 is disposed on the first medium 120, the reflective surface 121 is used to reflect the detection light. The emission direction of the reflected detection light passing through the reflective surface forms an angle with the first surface of the substrate 110 on which the first medium 120 is located. The angle mentioned here can be 90°, or it can be an acute angle with the extension direction of the emitting medium 120, or it can be an obtuse angle with the extension direction of the emitting medium 120. The specific design can be made according to the light emission requirements.

[0048] Since the echo light reflected back from the target object has the same exit angle as the corresponding detection light, meaning the corresponding echo light is parallel to the detection light, if the extension direction of the second medium 130 is perpendicular to the first medium 120, then the end face of the second end of the second medium 130 can be a plane parallel to the first surface. In this way, the echo light reflected back from the target object can couple into the second medium 130 through the end face of the second end. However, when the extension direction of the second medium 130 is in other directions, whether the end face of the second end of the second medium 130 is a plane parallel to the first surface or an inclined reflecting surface 121 depends on the extension direction of the second medium 130 and the inclination angle of the echo light. If the tilt angle of the echo light is 60° and the extension direction of the second medium 130 is parallel to the first surface, then if the end face of the second end is a plane perpendicular to or parallel to the first surface, the echo light cannot couple into the second medium. Therefore, the end face of the second end should be a tilted reflective surface 121 so that the tilt angle of the echo light can be deflected from 60° to 0° or other angles, so that enough echo light can couple into the second medium 130 through the reflective surface 121 to ensure the detection requirements of the lidar.

[0049] When the reflective surface 121 is disposed on the second medium 130, the principle is the same as above. Only when the preset included angle between the first medium 120 and the second medium 130 is within a certain range (such as 90° ± preset value) can the first end of the first medium 120 be a plane perpendicular to the first surface. In other cases, the first end of the first medium 130 also needs to be provided with the reflective surface 121.

[0050] It should be noted that when both the first end of the first medium 120 and the second end of the second medium 130 include an inclined reflective surface 121, the inclination angles of the two reflective surfaces 121 may be the same or different, depending on the extension direction of the first medium 120 and the second medium 130.

[0051] 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.

[0052] However, in a lidar system, as described earlier regarding the scanning module 400, such as... Figure 2As 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.

[0053] Firstly, in this embodiment, the corresponding first and second media are used to transmit the detection light and the echo light. This transceiver module design allows for precise positioning during production without requiring assembly through precise displacement, which helps improve production efficiency and thus improves the production efficiency of the lidar. The corresponding first and second media are used to transmit the detection light and the echo light, respectively, and a reasonable interval between the first and second media is set along the hysteresis direction, which can solve the problem of reception hysteresis.

[0054] Secondly, using the lidar provided in the embodiments of the present invention, the first medium and the second medium can transmit or receive light through the same scanning module, realizing integrated transmission and reception. There is no need to use a free space optical circulator, which reduces hardware overhead, lowers costs, simplifies the system, reduces the complexity of the optomechanical system, reduces the size of the entire system, and at the same time weakens the preamble signal and improves reliability.

[0055] Thirdly, the extension directions of the corresponding first and second media form a preset angle. One end of the first medium and the second end of the second medium are used to emit the detection light, and the other end is used to couple the echo light. At least one of the first and second ends includes an inclined reflective surface. Thus, the transceiver module 100 provided in this embodiment of the invention allows the originally horizontally propagating detection light or echo light to propagate perpendicular to the extension direction of the first medium 120 or the second medium 130 or at other angles. This ensures that even if the echo light is offset by ≥0.05° in the X direction compared to the detection light due to the receiving angle lag effect, it can still be received by the receiving medium in the first medium 120 and the second medium 130. Therefore, using the transceiver module provided in this embodiment of the invention, the optical path can be deflected by the reflective surface, making the optical path of the transceiver module not parallel to the substrate. Vertically arranging the transceiver module enables the stacking of transceiver units composed of the first and second media in the vertical direction, which can effectively improve the resolution of the lidar in the vertical direction and improve the detection accuracy of the lidar. In addition, during use, by controlling the transceiver module to move back and forth in the vertical direction, the number of light rays in the vertical direction of the lidar can be increased, thereby improving the vertical resolution of the lidar.

[0056] Therefore, the lidar provided in this embodiment of the invention can effectively improve the echo light reception rate in the horizontal direction, thereby reducing the adverse effects of the horizontal reception angle lag effect on detection and improving detection accuracy. At the same time, the transceiver module 100 and lidar provided in this embodiment of the invention have high reliability, low production cost, and high production efficiency.

[0057] In an optional embodiment, the extension directions of the first medium 120 and the second medium 130 are perpendicular to each other. Specifically, the first medium 120 extends along a first direction A, and the second medium 130 extends along a second direction B. 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 second direction B can be the height direction of the substrate 110, or other directions perpendicular to the first direction.

[0058] The first medium 120 is disposed on the first surface of the substrate 110, and the first end of the first medium 120 includes the aforementioned reflective surface 121. In this case, the end face of the second end of the second medium 130 can be a plane parallel to the first surface. Using the structure provided in this embodiment, the reflective surface 121 is provided on only one medium, which meets the usage requirements and facilitates processing.

[0059] In an optional embodiment, in the two corresponding media, at least half of the light-transmitting area of ​​the second medium on the first surface is located outside the second projection area of ​​the first medium on the first surface, and the distance between the first projection area and the second projection area is less than or equal to twice the width of the projection area of ​​the medium used to receive and transmit the echo signal on the first surface.

[0060] It should be noted that the distance between the first projection area and the second projection area mentioned here refers to the distance between the edge of the first projection area closest to the second projection area and the edge of the second projection area closest to the first projection area. Figure 7 The length of 'a' in the equation.

[0061] Specifically, the light-transmitting area of ​​the second medium 130 and the projection area of ​​the first medium 120 on the same surface (first surface) may or may not overlap. When they overlap, the area of ​​the overlapping area should be less than or equal to half the area of ​​the light-incident surface of the second medium 130. In this case, the overall structure of the transceiver module is relatively compact, and the light-incident surface of the second medium 130 can receive enough echo signals to meet the detection needs of the lidar. When they do not overlap, such as... Figure 7 As shown, the distance 'a' between the first projection area and the second projection area should be less than or equal to twice the width 'b' of the light-incident surface of the second medium 130. The width of the light-incident surface of the second medium 130 refers to its length in the extension direction of the first medium 120. This arrangement ensures that most of the echo signal can be received by the second medium 130, thus ensuring that the ranging capability of the lidar using the transceiver module 100 provided in this embodiment meets the requirements.

[0062] In the above embodiments, one or more first medium 120 and second medium 130 can be provided. However, when both first medium 120 and 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 5 and Figure 6 As shown, there are multiple first media 120 and multiple second media 130 respectively. The multiple first media 120 are arranged in parallel and spaced apart, and the multiple second media 130 are arranged in parallel and spaced apart.

[0063] 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 substrate. 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 set according to the required transmission field of view, enabling adjustment of the transmission field of view and meeting the needs of customers in different scenarios.

[0064] At the same time, when multiple first media 120 are arranged sequentially in the vertical direction, the resolution of the lidar in the vertical direction can be effectively improved.

[0065] In an optional embodiment, the distance between the two media is less than 10 μm when the entire second medium is located outside the projection area of ​​the first medium. This configuration ensures that the second medium can receive the vast majority of the echo light, thereby ensuring the ranging capability of the lidar using the transceiver module provided in this embodiment.

[0066] In the above embodiments, the light-emitting ends of the multiple first media can be flush or not flush. Since the interval between the corresponding first and second media remains unchanged, when the light-emitting ends of the multiple first media are flush, the light-incident surfaces of the multiple second media are also flush; when the light-emitting ends of the multiple first media are not flush, the light-incident surfaces of the multiple second media are also not flush. When the light-emitting ends of the multiple first media and the light-incident surfaces of the multiple second media are flush, it is convenient for design and manufacturing; when the light-emitting ends of the multiple first media and the light-incident surfaces of the multiple second media are not flush, the horizontal resolution of the lidar using this transceiver module can be improved.

[0067] To ensure effective reception while avoiding material waste, in one optional embodiment, the spacing between two adjacent first media is greater than 20 μm. The spacing between two adjacent second media is also greater than 20 μm.

[0068] 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°.

[0069] In an optional embodiment, such as Figure 5As shown, the centers of multiple reflective surfaces are located on the same straight line. Specifically, this straight line can be a line extending along a third direction C perpendicular to the first direction A and the second direction B, or it can be a line forming an angle with the third direction C. The specific setting can be flexibly determined according to the detection requirements.

[0070] In another optional embodiment, at least one reflective surface is offset from the other reflective surfaces, which can be flexibly set according to the detection requirements. This structure allows the transceiver module to have better light reception for certain special scenarios.

[0071] In one optional embodiment, the angle between the reflecting surface and the extending direction of the first medium is 30°-60°. The above-mentioned angle of the reflecting surface 121 can meet general detection requirements. The specific angle can be set according to the detection requirements and actual detection effect of different lidars, and is not limited here.

[0072] In a specific embodiment, such as Figure 3 As shown, the substrate 110 is located on the light-emitting side of the first medium 120, and the angle between the reflective surface 121 and the extension direction of the first medium 120 is 45°.

[0073] 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:

[0074] The first type, where both the first and second media are optical fibers, such as... Figures 3 to 6 As shown;

[0075] The second type involves both the first and second dielectrics being waveguides, such as... Figure 8 and Figure 9 As shown;

[0076] The third type uses a waveguide as the first medium and an optical fiber as the second medium.

[0077] The fourth type uses optical fiber as the first medium and waveguide as the second medium.

[0078] In all the above cases, the waveguide can be any of the following: single-mode waveguide, multi-mode waveguide, single-mode to multi-mode, or multi-mode to single-mode structure. The waveguide material can be SiO2, organic polymer, or silicon.

[0079] When both the first and second media are waveguides, the transceiver module is a planar waveguide chip with a substrate as the base. During manufacturing, an organic polymer can be directly imprinted onto two adjacent surfaces of the substrate corresponding to the laser wavelength used, forming a transmitting waveguide and a receiving waveguide, using a nanoimprinting process. Then, the light-emitting surface of the transmitting waveguide is beveled and coated to form a reflecting surface, such as... Figure 8 As shown; it can also be as follows Figure 9 As shown, the transmitting and receiving waveguides are first fabricated on two separate substrates, and then assembled together 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. This transceiver module configuration not only improves the detection accuracy, reliability, and production efficiency of the corresponding lidar, but also effectively eliminates the problem that a one-dimensional waveguide array of a planar waveguide chip cannot arbitrarily deflect light in the vertical direction.

[0080] Furthermore, when the transceiver module has multiple transmitting and receiving waveguides, compared to the design method of setting multiple sets of transmitting and receiving waveguides on the planar waveguide chip through 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 Lightwavecircuit) wafer, thereby effectively reducing the production cost of the transceiver module and improving production efficiency.

[0081] In all the above scenarios, the optical fiber can be single-mode fiber, multi-mode fiber, large-mode-field fiber, or single-mode to multi-mode fiber or multi-mode to single-mode fiber; the specific choice can be made flexibly according to the application requirements. For example... Figure 3 As shown, the optical fiber has a core 122 and an insulating portion 123 surrounding and coaxially disposed around the core 122. In use, the insulating portion 123 at the end of the optical fiber closest to another medium can be removed to expose the core 122. If the optical fiber is the first medium, a bevel is further processed on the end face of the core to form a reflective surface 121 so that the probe light or echo light can exit the optical fiber through the extended portion.

[0082] When at least one of the first and second media is an optical fiber, the substrate generally includes a first component and a second component. The first component is used to fix the first media, and the second component is used to fix the second media. In this case, the substrate used to fix the optical fiber can be a glass substrate, and the substrate used to fix the waveguide can be a ferrule. During fabrication, the first media and a portion of the substrate are first assembled into a whole, and the second media and another portion of the substrate are assembled into a whole. Then, the two are assembled into a single unit using precision assembly. Of course, when both the first and second media are waveguides, the substrate can also include a first component and a second component, where the first component is used to fix the first media and the second component is used to fix the second media. The specific choice can be flexibly made according to the application requirements, and no single limitation is made here.

[0083] In a specific embodiment, such as Figure 5 and Figure 6As shown, both the first and second media are optical fibers, and each has multiple first and second media. Specifically, the transceiver module has a horizontally placed fiber array (FA-A) and a vertically placed fiber array (FA-B), arranged close together with their end faces perpendicular to each other. Each fiber in FA-A and FA-B corresponds one-to-one. FA-A, used for emitting probe light, is the first media array, and its output end forms a 45° reflective surface. This design is small in size, highly integrated, and can be manufactured and assembled using mature processes, resisting temperature shocks. Furthermore, this design has a low preamble signal, making it suitable for various FMCW transceiver solutions.

[0084] For ease of assembly, in the above embodiments, the length of the core of the transmitting optical fiber extending beyond the insulation portion is generally greater than or equal to the radius of the insulation portion of the receiving optical fiber; and / or the length of the core of the receiving optical fiber extending beyond the insulation portion is generally greater than or equal to the radius of the insulation portion of the transmitting optical fiber.

[0085] To achieve stable fixation of the optical fiber, when at least one of the first and second media is an optical fiber, such as... Figure 5 and Figure 6 As shown, a V-groove is formed on the surface of the substrate for contacting the optical fiber, and the V-groove is used to accommodate the optical fiber. That is, the substrate includes a first part and a second part, wherein the first part is used to fix a first medium, and the second part is used to fix a second medium. When the first medium is an optical fiber, the first part has a V-groove for accommodating the first medium; when the second medium is an optical fiber, the second part has a V-groove for accommodating the second medium.

[0086] To further improve the stability of the connection between the optical fiber and the substrate, the optical fiber can be bonded to the V-groove using adhesive or similar substances.

[0087] 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, 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 effectively reduces the probability of emission and reflection of the probe light or echo light when it passes through the surface of the light-transmitting area in the first medium 120 or the surface of the light-transmitting area in the second medium 130, thereby increasing the amount of probe light emitted and the amount of echo light received. This results in the lidar receiving more echo light, thus improving the ranging capability of the lidar using the transceiver module 100 provided in the above embodiments.

[0088] In an optional embodiment, the substrate 110 is located on the light-transmitting side of the first medium 120 and the second medium 130, i.e., 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 and the second surface opposite to the first surface of the substrate 110. The light-transmitting area referred to here means all areas of the first and second surfaces that can be passed through by the probe light and / or the echo light, including the area of ​​the first surface other than the area covered by the first medium 120, and the entire area of ​​the second surface.

[0089] 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 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.

[0090] 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.

[0091] 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.

[0092] like Figure 10 As shown, the aforementioned lidar can be a frequency modulated continuous wave (FMCW) lidar. The FMCW 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.

[0093] 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.

[0094] In a specific embodiment, such as Figure 10 As shown, the transmitting module 200 includes a laser source and a collimation module. The laser source adopts a DFB+EDFA configuration, and both the first and second media are optical fibers. The first medium has a total of N (N≥1) paths, with each path having equal optical power. Correspondingly, the second medium also has N paths. The beam splitting module 500 is used to split the light 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 receiver module 600 as local oscillator light. The receiver module 600 includes a silicon photonic coherent receiver chip.

[0095] Before the DFB laser output reaches the EDFA optical amplifier, it is first coupled into the silicon photonic coherent receiver chip via a 500 beam splitter and an M-channel low-power optical fiber as the local oscillator. The detector in the silicon photonic coherent receiver chip can perform polarization diversity or not. The silicon photonic coherent receiver chip has a balanced detector diode, which performs coherent detection by mixing with the local oscillator. The receiver module, through a signal conditioning and processing module, calculates the detected beat frequency into velocity and distance information. The signal conditioning circuit also acquires the MZI delay path and the local oscillator beat frequency signal for closed-loop nonlinear correction of the DFB laser. Control and processing algorithms process the acquired raw data to calculate the current distance, velocity, direction, reflectivity, and other information. 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.

[0096] 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).

[0097] The above description is merely a preferred embodiment of the present invention and only specifically describes 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 in that, The system includes a substrate and a first medium and a second medium disposed on the substrate. The first medium and the second medium are disposed correspondingly, and the extension directions of the corresponding first medium and the second medium form a preset angle. One end of the first medium and the second medium is used to emit a probe light, and the other end is used to couple an echo light. At least one of the first end and the second end includes an inclined reflective surface, which is used to deflect the light. The extension directions of the first medium and the second medium are perpendicular to each other. The first medium is disposed on a first surface of the substrate, and the first end includes the reflective surface.

2. The transceiver module as described in claim 1, characterized in that, In the two corresponding media, at least half of the first projection area of ​​the light-transmitting area of ​​the second medium on the first surface is located outside the second projection area of ​​the first medium on the first surface, and the distance between the first projection area and the second projection area is less than or equal to twice the width of the projection area of ​​the medium used to receive and transmit the echo signal on the first surface.

3. The transceiver module as described in claim 1, characterized in that, The angle between the reflective surface and the extending direction of the first medium is 30°-60°.

4. 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-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.

5. The transceiver module as described in claim 1, characterized in that, Both the first medium and the second medium are provided in multiples, with the multiple first media arranged in parallel and spaced apart, and the multiple second media arranged in parallel and spaced apart.

6. The transceiver module as described in claim 5, characterized in that, The distance between two adjacent first media and between two adjacent second media is greater than 20 μm.

7. The transceiver module as described in claim 1, characterized in that, The first medium is either a waveguide or an optical fiber, and the second medium is also either a waveguide or an optical fiber.

8. The transceiver module as described in claim 7, characterized in that, The substrate includes a first part and a second part, wherein the first part is used to fix the first medium and the second part is used to fix the second medium.

9. The transceiver module as described in claim 8, characterized in that, When the first medium is an optical fiber, the first part is provided with a V-groove for accommodating the first medium; when the second medium is an optical fiber, the second part is provided with a V-groove for accommodating the second medium.

10. The transceiver module as described in any one of claims 1-9, 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.

11. 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 1-10. 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.

12. The lidar as described in claim 11, characterized in that, The scanning module is used to deflect light rays in the X and Y directions.

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