CN117008087B - Optical transceiver and laser radar based on planar waveguide chip - Google Patents

Abstract

The application provides an optical transceiver based on a planar waveguide chip and a laser radar, wherein the optical transceiver comprises: the upper surface of the step substrate comprises a first step upper surface and a second step upper surface, and the first step upper surface and the second step upper surface are positioned on planes which are parallel to the bottom surface of the step substrate and have different heights; the ladder waveguide chip is arranged on the ladder substrate and comprises a first plane waveguide chip and a second plane waveguide chip, the first plane waveguide chip and the second plane waveguide chip are both used for emitting laser and receiving echoes and outputting the echoes, the first plane waveguide chip is arranged on the first ladder upper surface of the ladder substrate, and the second plane waveguide chip is arranged on the second ladder upper surface of the ladder substrate. The application improves the overall receiving efficiency of the laser radar in the lag angle of the horizontal direction and the vertical direction relative to the target, thereby improving the detection capability of the laser radar.

Description

Optical transceiver and laser radar based on planar waveguide chip

Technical Field

The present application belongs to the field of laser radar detection technology, and in particular, relates to an optical transceiver and a laser radar based on a planar waveguide chip.

Background Art

The 4D (Four Dimensional) perception sensor module of the Frequency Modulated Continuous Wave (FMCW) LiDAR can measure distance and speed at the same time, and can provide more environmental target information in the fields of smart transportation, autonomous driving, assisted driving, navigation, mapping, meteorology, aerospace, robotics, etc. Compared with the time of flight (ToF) speed and distance measurement method, the FMCW LiDAR (Light Detection and Ranging, LiDAR) can obtain speed dimension information in one frame of detection data, which allows the FMCW LiDAR system to identify targets in the environment faster and transmit them to the information processing system at a faster speed to make adaptive operations in advance.

A scanning module with a two-dimensional MEMS (Micro-Electro-Mechanical System) galvanometer or two one-dimensional MEMS galvanometers scans the target in the horizontal and vertical directions. Since it takes time for light to propagate in space, the galvanometer of the scanning module will vibrate periodically during this time, and the galvanometer forms a hysteresis angle in the horizontal and vertical directions relative to the target. The galvanometer with a hysteresis angle makes the optical path of the echo reflected from the target different from the reverse optical path of the laser emission optical path. When receiving the echo reflected from the target, the laser radar cannot simultaneously receive the echo with hysteresis angles in both dimensions, resulting in low echo reception efficiency, which in turn affects the detection performance of the laser radar.

Summary of the invention

The embodiments of the present application provide an optical transceiver and a laser radar based on a planar waveguide chip, which aims to solve the problem that a scanning module with a galvanometer has a detection light lag angle in two dimensions, horizontal and vertical, relative to the target. When receiving the echo reflected by the target, the laser radar cannot simultaneously receive the echo with lag angles in these two dimensions, resulting in low overall echo reception efficiency, which in turn affects the detection performance of the laser radar.

A first aspect of an embodiment of the present application provides an optical transceiver based on a planar waveguide chip, which is applied to a laser radar, including:

A stepped base, wherein the upper surface of the stepped base comprises a first stepped upper surface and a second stepped upper surface, wherein the first stepped upper surface and the second stepped upper surface are located in planes parallel to the bottom surface of the stepped base and at different heights;

A stepped waveguide chip is arranged on the stepped substrate, the stepped waveguide chip includes a first planar waveguide chip and a second planar waveguide chip, the first planar waveguide chip and the second planar waveguide chip are both used for emitting lasers and for receiving echoes and outputting the echoes, wherein the first planar waveguide chip is arranged on the first stepped upper surface of the stepped substrate, and the second planar waveguide chip is arranged on the second stepped upper surface of the stepped substrate.

In one embodiment, the first planar waveguide chip contacts the second planar waveguide chip in a first direction, and the first direction is a lateral direction parallel to the bottom surface of the step substrate and having different heights along the top surface of the step substrate.

In one embodiment, the first planar waveguide chip and the second planar waveguide chip respectively include at least one transceiver waveguide structure, and the multiple transceiver waveguide structures in the first planar waveguide chip and the second planar waveguide chip are arranged in parallel and spaced apart along the second direction, and extend from one end to the other end of the step waveguide chip along the third direction, and the transceiver waveguide structure is used to emit the laser and to receive the echo and output the echo, wherein the second direction is a direction perpendicular to the bottom surface of the step base, and the third direction is a longitudinal direction parallel to the bottom surface of the step base and extending at the same height along the upper surface of the step base, and the second direction is perpendicular to both the first direction and the third direction.

In one embodiment, the transceiver waveguide structure includes a first waveguide structure for emitting the laser and at least one second waveguide structure for receiving the echo and outputting the echo, and the second waveguide structure is arranged on at least one side of the first waveguide structure.

In one of the embodiments, the first waveguide structure is a single-mode waveguide structure;

The second waveguide structure is any one of a multi-mode to single-mode waveguide structure, a large-mode to single-mode waveguide structure, a few-mode to single-mode waveguide structure and the single-mode waveguide structure.

In one embodiment,

At least one of the second waveguide structures in the same transceiver waveguide structure has a preset inclination angle relative to the first waveguide structure.

In one embodiment, the preset inclination angle is ≦0.1 degrees.

In one embodiment, a first interval between an emitting end of the first waveguide structure and an input end of the adjacent second waveguide structure is K, wherein 0.1×W≦K≦0.2×W, and W is a waveguide width of a single-mode waveguide structure in the first waveguide structure or the second waveguide structure.

In one of the embodiments, in the second direction, the plurality of transceiver waveguide structures of the first planar waveguide chip and the plurality of transceiver waveguide structures of the second planar waveguide chip are staggered with each other; and/or

In the second direction, a first spacing is greater than or equal to 50 μm, and the first spacing is a vertical distance between adjacent transceiver waveguide structures in the first planar waveguide chip or the second planar waveguide chip.

In one of the embodiments, in the first direction, the first planar waveguide chip and the second planar waveguide chip both include a plurality of transceiver waveguide structures arranged in an array.

In one of the embodiments, the optical transceiver device further includes a transceiver lens, and the transceiver lens is disposed at the transmitting end of the first waveguide structure in the transceiver waveguide structure.

In one of the embodiments, in the first direction, the second spacing is less than or equal to one tenth of the diameter of the transceiver lens, and the second spacing is the vertical distance between the mutually adjacent sides of the transceiver waveguide structure of the first planar waveguide chip and the transceiver waveguide structure of the second planar waveguide chip.

A second aspect of the embodiments of the present application provides a laser radar, comprising a laser emission module, a scanning module, a detection module, a signal processing module, and an optical transceiver device as claimed in any one of claims 1 to 12;

The laser emission module is used to output laser light, split the laser light to obtain N laser light paths and M local oscillator light paths, and output the N laser light paths and the M local oscillator light paths respectively, wherein M and N are both positive integers, N≧2, M≧2;

The optical transceiver is used to access the laser beams of each of the N laser beams and output the laser beams of each laser beam respectively;

The scanning module is used to connect to each channel of the laser and emit each channel of the laser to the target for scanning. The scanning module is also used to receive the echo reflected by the target and then output the echo;

The optical transceiver is further used to receive the echo and output the echo;

The detection module has M detection units, each of which is connected to one of the M lasers, and the detection unit is used to connect the echo and mix the echo with the connected local oscillator light to obtain a corresponding beat frequency electrical signal;

The signal processing module is used to access each of the beat frequency electrical signals and process them to obtain the detection information of the target.

Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

An embodiment of the present application provides an optical transceiver based on a planar waveguide chip. When a laser radar with a galvanometer scans a target, since the galvanometer forms a lag angle in both the horizontal and vertical directions relative to the target, an optical transceiver based on a planar waveguide chip with receiving and transmitting functions is arranged on the echo optical path corresponding to these two dimensions, and echoes with lag angles in the two dimensions are received simultaneously, thereby improving the overall echo receiving efficiency of the laser radar in both the horizontal and vertical directions relative to the target, improving the resolution in these two directions, and thereby improving the detection performance of the laser radar.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram of a 45° viewing angle of an optical transceiver device based on a planar waveguide chip provided by an embodiment of the present application;

FIG2 is a schematic diagram of another optical transceiver device based on a planar waveguide chip provided in an embodiment of the present application at a viewing angle of 45°;

FIG3 is a schematic diagram of a 45° viewing angle of another optical transceiver device based on a planar waveguide chip provided by an embodiment of the present application;

FIG4 is a schematic diagram of a 45° viewing angle of another optical transceiver device based on a planar waveguide chip provided in an embodiment of the present application;

FIG5 is a schematic top view of an optical transceiver device based on a planar waveguide chip according to FIG1 provided in one embodiment of the present application;

FIG6 is a schematic top view of an optical transceiver device based on a planar waveguide chip according to FIG2 provided in one embodiment of the present application;

FIG. 7 is a schematic top view of an optical transceiver device based on a planar waveguide chip according to FIG. 3 provided in one embodiment of the present application;

FIG8 is a schematic top view of an optical transceiver device based on a planar waveguide chip according to FIG4 provided in one embodiment of the present application;

FIG9 is a front view schematic diagram of an optical transceiver device based on a planar waveguide chip according to FIG1 provided in one embodiment of the present application;

FIG10 is a front view schematic diagram of an optical transceiver device based on a planar waveguide chip according to FIG2 provided in one embodiment of the present application;

FIG11 is a front view schematic diagram of an optical transceiver device based on a planar waveguide chip according to FIG3 provided in one embodiment of the present application;

FIG12 is a front view schematic diagram of an optical transceiver device based on a planar waveguide chip according to FIG4 provided in one embodiment of the present application;

13 is a schematic diagram of an echo spot with a hysteresis angle received by an optical transceiver based on a planar waveguide chip provided by an embodiment of the present application;

14 is a schematic diagram of an echo spot with a hysteresis angle received by another optical transceiver based on a planar waveguide chip provided by an embodiment of the present application;

15 is a schematic top view of an optical transceiver device based on a planar waveguide chip, in which a second waveguide structure has a preset inclination angle, provided in one embodiment of the present application;

16 is a schematic top view of another optical transceiver device based on a planar waveguide chip in which a second waveguide structure has a preset inclination angle provided by an embodiment of the present application;

17 is a top view of a transmitting and receiving lens disposed at a transmitting end of a first waveguide structure of an optical transceiver device based on a planar waveguide chip provided in an embodiment of the present application;

18 is a top view of another optical transceiver device based on a planar waveguide chip provided in accordance with an embodiment of the present application, in which a transceiver lens is arranged at a transmitting end of a first waveguide structure;

19 is a front view schematic diagram of the position of a transceiver lens disposed at a transmitting end of a first waveguide structure of an optical transceiver device based on a planar waveguide chip provided in one embodiment of the present application;

20 is a front view schematic diagram of the position of the transceiver lens disposed at the transmitting end of the first waveguide structure of another optical transceiver device based on a planar waveguide chip provided by an embodiment of the present application;

FIG. 21 is a schematic diagram of the structure of a laser radar provided in one embodiment of the present application.

DETAILED DESCRIPTION

In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, modules, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

The technical solution of the present application is described below through specific embodiments.

The scanning module provided in the embodiment of the present application includes a galvanometer (also called a "scanning galvanometer"), and the galvanometer includes a mechanical galvanometer and a MEMS (Micro-Electro-Mechanical System) galvanometer, wherein the MEMS galvanometer may include but is not limited to a one-dimensional MEMS galvanometer and a two-dimensional MEMS galvanometer.

In one embodiment, the scanning module includes a mechanical galvanometer or a one-dimensional MEMS galvanometer. The mechanical galvanometer and the one-dimensional MEMS galvanometer emit the laser beam emitted to the reflector through a rotating mirror to a horizontal field of view that is horizontal to the target, or emit the laser beam emitted to the reflector through a rotating mirror to a vertical field of view that is vertical to the target. The scanning module with the mechanical galvanometer and the one-dimensional MEMS galvanometer can realize scanning detection of a certain field of view angle.

The laser is output from the laser transmitting module, passes through the optical transceiver, and is emitted to the target through the mechanical galvanometer or one-dimensional MEMS galvanometer in the scanning module. The echo signal reflected from the target passes through the scanning module and is then transmitted from the optical transceiver to the detection module. During the transmission time from the laser emitted by the laser radar to the target and then reflected back from the target, the mechanical galvanometer or one-dimensional MEMS galvanometer in the scanning module has formed a certain angle in the direction of one dimension, thus forming a lag angle of the mechanical galvanometer or one-dimensional MEMS galvanometer in the direction of one dimension. The lag angle of the mechanical galvanometer or one-dimensional MEMS galvanometer in this dimensional direction prevents the reflected echo signal from returning to the optical transceiver along the reverse optical path of the outgoing optical path, resulting in the echo reflected from the target not being efficiently received by the same receiving waveguide on the optical transceiver, affecting the detection performance of the laser radar.

In another embodiment, the scanning module includes a two-dimensional MEMS galvanometer, which includes a first axis and a second axis. The first axis and the second axis are perpendicular to each other. The first axis drives the reflector in the scanning galvanometer to vibrate, so that the laser beam emitted to the reflector can be reflected to a horizontal field of view that is horizontal to the target; the second axis also drives the reflector in the scanning galvanometer to vibrate, thereby reflecting the laser beam emitted to the reflector to a vertical field of view that is vertical to the target. Under the joint driving action of the first axis and the second axis, the reflector can realize scanning detection of a certain field of view angle.

In another embodiment, when the scanning module includes two one-dimensional MEMS galvanometers, the optical axes of the two one-dimensional MEMS galvanometers are perpendicular to each other, one of the one-dimensional MEMS galvanometers can reflect the laser beam emitted to the reflector to a horizontal field of view that is horizontal to the target; the other one-dimensional MEMS galvanometer reflects the laser beam emitted to the reflector to a vertical field of view that is vertical to the target. Under the joint action of the two one-dimensional MEMS galvanometers, the scanning module can realize scanning detection of a certain field of view angle.

When the scanning module includes a two-dimensional MEMS galvanometer, or includes two one-dimensional MEMS galvanometers, the laser is output from the laser emission module through the optical transceiver, and then emitted to the target through the two-dimensional MEMS galvanometer or two one-dimensional MEMS galvanometers in the scanning module. The echo signal reflected from the target passes through the scanning module and is then transmitted from the optical transceiver to the detection module. During the transmission time from the laser emitted by the laser radar from the emission to the target and then reflected back from the target, the two-dimensional MEMS galvanometer or two one-dimensional MEMS galvanometers in the scanning module form a certain angle when they periodically vibrate in two mutually perpendicular directions, forming a hysteresis angle of the two-dimensional MEMS galvanometer or two one-dimensional MEMS galvanometers in the vertical and horizontal directions relative to the target. The lag angles of a two-dimensional MEMS galvanometer or two one-dimensional MEMS galvanometers in two dimensions prevent the reflected echo signal from returning to the optical transceiver along the reverse optical path of the outgoing optical path, resulting in the echo reflected by the target not being efficiently received by the same receiving waveguide structure on the optical transceiver at the same time. The lag angle of the galvanometer in the horizontal direction relative to the target is larger than the lag angle in the vertical direction relative to the target, resulting in low overall echo reception efficiency, which in turn affects the detection performance of the lidar.

In a first aspect, an embodiment of the present application provides an optical transceiver 20 based on a planar waveguide chip, as shown in FIG1 , which is applied to a laser radar, including:

A stepped base 21, wherein the upper surface of the stepped base 21 includes a first stepped upper surface and a second stepped upper surface, wherein the first stepped upper surface and the second stepped upper surface are located in planes parallel to the bottom surface of the stepped base 21 and at different heights;

The step waveguide chip 22 is arranged on the step substrate 21, and the step waveguide chip 22 includes a first planar waveguide chip 221 and a second planar waveguide chip 222. The first planar waveguide chip 221 and the second planar waveguide chip 222 are both used for emitting lasers and for receiving echoes and outputting echoes, wherein the first planar waveguide chip 221 is arranged on the first step upper surface of the step substrate 21, and the second planar waveguide chip 222 is arranged on the second step upper surface of the step substrate 21. The step substrate 21 has a mechanical support function, and the substrate material is any one of silicon dioxide, silicon, and a transparent polymer, and can also be other infrared-transmitting materials.

When a laser radar with a galvanometer performs a two-dimensional array scanning on a target, since the echo reflected by the target has a lag angle in two dimensional directions corresponding to the first axis and the second axis of the galvanometer, this embodiment simultaneously receives the echoes with lag angles in two dimensional directions corresponding to the first axis and the second axis of the galvanometer by arranging an optical transceiver of a planar waveguide chip for receiving and outputting echoes in two dimensional directions corresponding to the two axes, thereby improving the overall echo receiving efficiency of the laser radar in two dimensional directions of the vertical direction and the horizontal direction relative to the target, and also improving the resolution in these two dimensional directions, thereby improving the detection performance of the laser radar.

In one embodiment, as shown in FIG1 , the first planar waveguide chip 221 contacts the second planar waveguide chip 222 in a first direction, and the first direction is a lateral direction parallel to the bottom surface of the stepped substrate 21 and having different heights along the upper surface of the stepped substrate 21. The first planar waveguide chip 221 and the second planar waveguide chip 222 are arranged to contact in the first direction, so that the waveguide structures for receiving and outputting echoes in the first planar waveguide chip 221 and the second planar waveguide chip 222 are spaced at a smaller distance in the first direction, which is conducive to receiving echoes reflected by a close-range target through a galvanometer, thereby improving the overall reception efficiency of the echoes, and further improving the detection performance of the laser radar.

In one embodiment, as shown in FIG1 , the first planar waveguide chip 221 and the second planar waveguide chip 222 each include at least one transceiver waveguide structure, and multiple transceiver waveguide structures in the first planar waveguide chip 221 and the second planar waveguide chip 222 are arranged in parallel and spaced along the second direction, and extend from one end of the step waveguide chip 22 to the other end along the third direction, and the transceiver waveguide structure is used to emit laser light and receive echoes and output echoes, wherein the second direction is a direction perpendicular to the bottom surface of the step substrate 21, and the third direction is a longitudinal direction parallel to the bottom plane of the step substrate 21 and extending at the same height along the upper surface of the step substrate 21, and the second direction is perpendicular to the first direction and the third direction at the same time. For ease of understanding, as shown in FIG1 to FIG4 , an X-Y-Z spatial coordinate system is established in the drawings, wherein the first direction is the X direction, the second direction is the Z direction, and the third direction is the Y direction. This embodiment does not specifically limit the number of transceiver waveguide structures included in the first planar waveguide chip 221 and the second planar waveguide chip 222. The number of transceiver waveguide structures included in the first planar waveguide chip 221 and the second planar waveguide chip 222 can be equal or unequal, and is set according to the echo receiving efficiency and detection performance of the laser radar. For example, the first planar waveguide chip 221 includes 1 transceiver waveguide structure, and the second planar waveguide chip 222 also includes 1 transceiver waveguide structure; or, the first planar waveguide chip 221 includes 1 transceiver waveguide structure, and the second planar waveguide chip 222 includes 2 transceiver waveguide structures; or, the first planar waveguide chip 221 includes 2 transceiver waveguide structures, and the second planar waveguide chip 222 also includes 2 transceiver waveguide structures; or, the first planar waveguide chip 221 includes 2 transceiver waveguide structures, and the second planar waveguide chip 222 also includes 4 transceiver waveguide structures, etc.

At least one transceiver waveguide structure is provided in both the first planar waveguide chip 221 and the second planar waveguide chip 222, and a plurality of transceiver waveguide structures in the first planar waveguide chip 221 and the second planar waveguide chip 222 are arranged in parallel and spaced apart along the second direction. Since the first axis direction of the galvanometer corresponds to the horizontal direction relative to the target, and the second axis direction of the galvanometer corresponds to the vertical direction relative to the target, the transceiver waveguide structure arranged in the first direction in this embodiment corresponds to receiving the echo with a lag angle passing through the first axis direction of the galvanometer, and the transceiver waveguide structure arranged in the second direction in this embodiment corresponds to receiving the echo with a lag angle passing through the second axis direction of the galvanometer, which is beneficial for the optical transceiver device 20 to receive the echo reflected from the horizontal direction and the vertical direction relative to the target, thereby improving the overall reception efficiency of the echo, and further improving the detection performance of the laser radar.

A plurality of transceiver waveguide structures form a first planar waveguide chip 221 and a second planar waveguide chip 222. The first planar waveguide chip 221 and the second planar waveguide chip 222 are bonded together in a first direction to form a step waveguide chip 22. The step waveguide chip 22 is then packaged together with the corresponding step substrate 21, so that the transmitting component and the receiving component can be packaged as one, thereby improving the integration of the laser radar and enhancing the reliability.

In some embodiments, as shown in FIG. 1 and FIG. 2, the transceiver waveguide structure includes a first waveguide structure 223 for emitting laser light and at least one second waveguide structure 224 for receiving and outputting echoes, and the second waveguide structure 224 is arranged on at least one side of the first waveguide structure 223. Among them, in the first direction, the second waveguide structure 224 can be arranged on the left or right side of the first waveguide structure 223. Such a setting is conducive to the second waveguide structure 224 of the optical transceiver 20 receiving more echoes with echo spots on the left or right side of the first waveguide structure 223 after the return of the hysteresis angle, thereby improving the overall reception efficiency of the echo, and thus improving the detection performance of the laser radar. The laser light with the same wavelength or different wavelengths output by the laser is transmitted to the first waveguide structure 223, and the laser light is emitted through the first waveguide structure 223. The optical path direction of the laser emission is shown in FIG. 5 and FIG. 8. The second waveguide structure 224 on either side of the first waveguide structure 223 is used to receive the echo reflected by the target after the emitted laser light is emitted, and the optical path direction of the received echo is shown in FIG. 5 and FIG. 6.

In some embodiments, as shown in FIG. 1 and FIG. 2, the first waveguide structure 223 is a single-mode waveguide structure; the second waveguide structure 224 is any one of a multi-mode to single-mode waveguide structure, a large-mode to single-mode waveguide structure, a few-mode to single-mode waveguide structure, and a single-mode waveguide structure. For example, the first waveguide structure 223 of FIG. 1 is a single-mode waveguide structure, and the second waveguide structure 224 is any one of a multi-mode to single-mode waveguide structure, a large-mode to single-mode waveguide structure, and a few-mode to single-mode waveguide structure. FIG. 5 is a top view corresponding to FIG. 1, and FIG. 9 is a front view corresponding to FIG. 1; for example, the first waveguide structure 223 of FIG. 2 is a single-mode waveguide structure, and the second waveguide structure 224 is also a single-mode waveguide structure. FIG. 6 is a top view corresponding to FIG. 2, and FIG. 10 is a front view corresponding to FIG. 2.

As shown in FIG1 and FIG2 , the optical transceiver 20 has the second waveguide structure 224 only disposed on the left or right side of the first waveguide structure 223 in the first direction. Therefore, the reception efficiency of the echo having a lag angle only on either side in the first direction can be improved. Considering the cost, it is more suitable for a scanning module including a one-dimensional MEMS galvanometer and a rotating mirror, or is more suitable for a scanning module including a mechanical galvanometer and a rotating mirror, which can improve the detection performance of the laser radar.

In other embodiments, as shown in FIG. 3 and FIG. 4, the transceiver waveguide structure includes a first waveguide structure 223 for emitting laser light and at least two second waveguide structures 224 for receiving and outputting echoes, and the second waveguide structures 224 are provided on both sides of the first waveguide structure 223. Among them, in the first direction, the second waveguide structure 224 is provided on both sides of the first waveguide structure 223. Such a setting is conducive to the second waveguide structure 224 of the optical transceiver 20 receiving more echoes with echo spots on both sides of the first waveguide structure 223 after the return of the hysteresis angle, thereby improving the overall reception efficiency of the echo, and thus improving the detection performance of the laser radar. The laser light with the same wavelength or different wavelengths output by the laser is transmitted to the first waveguide structure 223, and the laser light is emitted through the first waveguide structure 223. The optical path direction of the laser emission is shown in FIG. 7 and FIG. 8. The second waveguide structures 224 on both sides of the first waveguide structure 223 are used to receive the echo reflected by the target after the emitted laser light is emitted, and the optical path direction of the received echo is shown in FIG. 7 and FIG. 8.

In some embodiments, as shown in FIG. 3 and FIG. 4 , the first waveguide structure 223 is a single-mode waveguide structure;

The second waveguide structure 224 is at least one of a single-mode waveguide structure, a multi-mode-to-single-mode waveguide structure, a large-mode-to-single-mode waveguide structure, and a few-mode-to-single-mode waveguide structure. For example, the first waveguide structure 223 of FIG. 3 is a single-mode waveguide structure, and the second waveguide structure 224 is any one of a multi-mode-to-single-mode waveguide structure, a large-mode-to-single-mode waveguide structure, and a few-mode-to-single-mode waveguide structure. FIG. 7 is a top view corresponding to FIG. 3 , and FIG. 11 is a front view corresponding to FIG. 3 ; for example, the first waveguide structure 223 of FIG. 4 is a single-mode waveguide structure, and the second waveguide structure 224 is a waveguide structure having two multi-mode, large-mode, or few-mode-to-single-mode waveguide structures on one side of the first waveguide structure 223. FIG. 8 is a top view corresponding to FIG. 4 , and FIG. 12 is a front view corresponding to FIG. 4 . It should be noted that when the number of second waveguide structures 224 is multiple, the same waveguide structure can be set on both sides of the first waveguide structure 223, or different waveguide structures can be set on both sides of the first waveguide structure 223. For example, a multi-mode to single-mode waveguide structure is set on one side of the first waveguide structure 223, and a large-mode to single-mode waveguide structure is set on the other side of the first waveguide structure 223.

As shown in FIG3 and FIG4 , the optical transceiver 20 has a second waveguide structure 224 disposed on both sides of the first waveguide structure 223 in the first direction, and the second waveguide structure 224 is disposed on both the left and right sides of the first waveguide structure 223. This can improve the efficiency of receiving echoes having a lag angle relative to both the left and right sides of the first waveguide structure 223 in the first direction. Considering the cost, it is more suitable for a scanning module including a two-dimensional MEMS galvanometer, or is more suitable for a scanning module including two one-dimensional MEMS galvanometers, which can improve the detection performance of the laser radar.

As shown in Fig. 8, in one direction, the number of the second waveguide structures 224 on one side of the first waveguide structure 223 is set to 2. In other embodiments, in one direction, the number of the second waveguide structures 224 on either side of the first waveguide structure 223 may also be set to 3, 4 or 5. This embodiment does not limit the number of second waveguide structures 224 on either side of the first waveguide structure 223, and the number of second waveguide structures 224 is set specifically according to the hysteresis angle range of the galvanometer of the laser radar and the echo receiving efficiency.

In the above embodiments, the first waveguide structure 223 is a single-mode waveguide structure, and the waveguide widths of the input end and the output end of the single-mode waveguide structure are the same. The input and output directions of the optical path of the laser emission are shown in Figures 5 to 8, which is convenient for the emitted laser energy to concentrate the power, increase the angular power of the emission, and reduce the area of the emission spot, which is beneficial to improving the resolution of the laser radar. The second waveguide structure 224 is at least one of a multi-mode to single-mode waveguide structure, a large mode to single-mode waveguide structure, a few-mode to single-mode waveguide structure, and a single-mode waveguide structure. The waveguide structure of the second waveguide structure 224 can be arbitrarily selected according to the ranging performance and resolution requirements of the laser radar. Taking the multi-mode to single-mode waveguide structure as an example, the multi-mode to single-mode waveguide structure includes an input end of the multi-mode waveguide structure and an output end of the single-mode waveguide structure. The input and output directions of the optical path for receiving the echo are shown in Figures 5, 7, and 8. The waveguide width of the multi-mode to single-mode waveguide structure gradually decreases from the input end of the multi-mode waveguide structure to the output end of the single-mode waveguide structure. The waveguide width of the output end of the single-mode waveguide structure in the multi-mode to single-mode waveguide structure is the same as the waveguide width of the output end of the single-mode waveguide structure. The input end of the multi-mode waveguide structure in the multi-mode to single-mode waveguide structure is conducive to increasing the receiving aperture of the echo.

In some embodiments, as shown in FIG. 15 and FIG. 16, at least one second waveguide structure 224 in the same transceiver waveguide structure has a preset inclination angle relative to the first waveguide structure 223. The first waveguide structure 223 and the second waveguide structure 224 on one or both sides are located on the same plane parallel to the plane where the bottom of the step base is located, and at least one second waveguide structure 224 on one or both sides of the first waveguide structure 223 has a preset inclination angle relative to the first waveguide structure 223. According to the principle of the hysteresis effect of the scanning reception angle and the structural setting of the laser radar scanning module, the specific angle of the hysteresis angle of the galvanometer can be obtained, and then the angle of the preset inclination angle is set to be equal to the angle of the hysteresis angle of the galvanometer generated by the scanning module 30 after scanning the farthest distance target, so that the echo signal can be further received by the input end of the second waveguide structure 224, thereby improving the reception efficiency of the echo and thus improving the detection performance of the laser radar. Optionally, the preset inclination angle is ≦0.2 degrees. The specific preset inclination angle is set according to the hysteresis angle of the galvanometer after scanning the farthest distance target generated by the scanning module 30. Further, for example, the preset inclination angle is set to be ≤0.1 degrees.

In some embodiments, as shown in FIG8 , the first waveguide structure 223 and the second waveguide structure 224 on one side or both sides of each transceiver waveguide structure can be closely arranged or arranged at a preset interval. Preferably, as shown in FIG5 , the first interval between the transmitting end of the first waveguide structure 223 and the input end of the adjacent second waveguide structure 224 is K, wherein 0.1×W≦K≦0.2×W, and W is the waveguide width of the single-mode waveguide structure in the first waveguide structure 223 or the second waveguide structure 224. As shown in FIGS. 13 and 14 , in the first direction, since the second waveguide structure 224 adjacent to the first waveguide structure 223 has an interval offset relative to the first waveguide structure 223 as a whole, the reflected echo light spot with a lag angle can be received by the input end of each waveguide structure in the offset multiple second waveguide structures 224, thereby improving the overall reception efficiency of the echo, effectively improving the problem of partial echo signal loss due to the lag in the detection light angle of the laser radar, and thus improving the detection performance of the laser radar.

Optionally, a first interval K between an output end of a first waveguide structure 223 and an input end of an adjacent second waveguide structure 224 is 1 μm.

Optionally, the second waveguide structure 224 is set as a plurality of second waveguide structures 224 on either side of the first waveguide structure 223, or the second waveguide structure 224 is set as a plurality of second waveguide structures 224 on both sides of the first waveguide structure 223, so as to expand the receiving aperture for receiving echoes with a lag angle and increase the receiving range of received echoes, so as to further improve the efficiency of receiving echoes, wherein the first interval between the input ends of adjacent second waveguide structures 224 is K, 0.1×W≦K≦0.2×W, and W is the waveguide width of the single-mode waveguide structure in the first waveguide structure 223 or the second waveguide structure 224.

In some embodiments, as shown in FIG1 and FIG9 , in the second direction, the multiple transceiver waveguide structures of the first planar waveguide chip 221 and the multiple transceiver waveguide structures of the second planar waveguide chip 222 are mutually staggered. Such a staggered arrangement reduces the spacing between adjacent first waveguide structures 223 for emitting lasers in the second direction, increases the number of detection laser lines in the vertical direction relative to the target, and improves the resolution capability of the laser radar.

In some embodiments, as shown in FIG. 1 and FIG. 9, in the second direction, the spacing between adjacent transceiver waveguide structures in the first planar waveguide chip 221 or the second planar waveguide chip 222 is set to a first spacing d1. The specific value of the first spacing d1 set between adjacent transceiver waveguide structures in each planar waveguide core is determined by the process of producing the planar waveguide, so that the waveguide surfaces of the two sub-planar waveguide chips in the first planar waveguide chip 221 or the second planar waveguide chip 222 are close to each other, preferably, d1≧50μm. As shown in FIG. 1 and FIG. 9, in the second direction, the first planar waveguide chip 221 and the second planar waveguide chip 222 each include two sub-planar waveguide chips. In one embodiment, in the first direction, the first waveguide structure 223 and at least one second waveguide structure 224 form a transceiver waveguide structure, and then at least one transceiver waveguide structure forms a sub-planar waveguide chip, and the waveguide surfaces of the two sub-planar waveguide chips are bonded to each other to form the first planar waveguide chip 221 or the second planar waveguide chip 222. The second waveguide structures 224 in the first planar waveguide chip 221 or the second planar waveguide chip 222 are close to each other, which is conducive to receiving more echoes with a hysteresis angle reflected back in the second direction, thereby improving the overall reception efficiency of the echoes. Optionally, in the second direction, the vertical distance between the center line of a transceiver waveguide structure of the first planar waveguide chip 221 extending along the first direction and the center line of an adjacent transceiver waveguide structure of the second planar waveguide chip 222 extending along the first direction is half of the first spacing d1. Such an arrangement in the second direction makes the adjacent transceiver waveguide structures in the first planar waveguide chip 221 or the second planar waveguide chip 222 more evenly arranged after the misaligned arrangement, which is conducive to the uniform emission of lasers and reception of echoes by the step waveguide chip 22.

In some embodiments, as shown in Figures 1 and 9, in the second direction, multiple transceiver waveguide structures of the first planar waveguide chip 221 and multiple transceiver waveguide structures of the second planar waveguide chip 222 are staggered with each other, and the spacing between adjacent transceiver waveguide structures in the first planar waveguide chip 221 or the second planar waveguide chip 222 is set to a first spacing d1, preferably, d1≧50μm.

In one embodiment, as shown in Figure 9, in the second direction, the fourth spacing is the vertical distance between the second step upper surface of the stepped substrate 21 and the bottom of the transceiver waveguide structure close to the lower surface of the second planar waveguide chip 222, and the fifth spacing is the vertical distance between the first step upper surface of the stepped substrate 21 and the bottom of the transceiver waveguide structure close to the lower surface of the first planar waveguide chip 221. The fourth spacing d4 or the fifth spacing d5 needs to be greater than half of the first spacing d1 to avoid the fourth spacing d4 or the fifth spacing d5 being smaller than the spacing between a transceiver waveguide structure of the first planar waveguide chip 221 and an adjacent transceiver waveguide structure of the second planar waveguide chip 222 in the second direction, resulting in uneven distribution of a transceiver waveguide structure of the first planar waveguide chip 221 and an adjacent transceiver waveguide structure of the second planar waveguide chip 222 in the second direction, affecting the performance of the laser radar. Preferably, the fourth spacing is greater than or equal to 25μm, that is, d4≧25μm, and the fifth spacing is greater than or equal to 25μm, that is, d5≧25μm. The fourth spacing and the fifth spacing can be equal or unequal, and are set specifically according to the manufacturing process of the optical transceiver and the detection requirements of the laser radar.

In one embodiment, in the first direction, the first planar waveguide chip 221 and the second planar waveguide chip 222 both include multiple transceiver waveguide structures arranged in an array. When the hysteresis angle range of the galvanometer is large, more multiple transceiver waveguide structures arranged in an array can improve the reception efficiency of the echo, and can also improve the resolution of the laser radar and enhance the detection performance of the laser radar.

In one embodiment, the transceiver waveguide structures arranged in an array in the first direction are arranged in a periodic manner, wherein in the first direction, the second interval is greater than or equal to half of the waveguide width of the single-mode waveguide structure of the first waveguide structure 223, and the second interval is the distance between adjacent transceiver waveguide structures in the first planar waveguide chip 221 or the second planar waveguide chip 222.

In some embodiments, for a certain sub-planar waveguide chip, taking the first waveguide structure 223 as a single-mode waveguide structure and the second waveguide structure 224 as a multi-mode to single-mode waveguide structure as an example, a plurality of transceiver waveguide structures are arranged in an equidistant periodic array, or each transceiver waveguide structure is arranged at unequal intervals, so that the transceiver field of view and direction of each path can be dynamically adjusted according to the receiving echo efficiency of the laser radar, thereby improving the measurement accuracy of the laser radar. The spacing between adjacent transceiver waveguide structures in a certain sub-planar waveguide chip is greater than or equal to half of the waveguide width of the single-mode waveguide structure. Optionally, the spacing between the input end of any waveguide structure in the transceiver waveguide structure and the output end of any waveguide structure in another adjacent transceiver waveguide structure is greater than or equal to 3μm.

As shown in FIGS. 1 to 4 , the first waveguide structure 223 and the second waveguide structure 224 in a transceiver waveguide structure are located on the same plane parallel to the plane where the bottom of the stepped substrate is located, which is convenient for manufacturing and production. At the same time, the first waveguide structure 223 and the second waveguide structure 224 are both located on the same plane, which improves the low echo reception efficiency caused by the angle hysteresis effect of the detection light in one dimensional direction, improves the echo reception efficiency in one dimensional direction, and makes the planar waveguide chip have the advantages of small size and low manufacturing cost, and can also improve the production efficiency of the planar optical waveguide chip.

In some embodiments, as shown in FIG17 and FIG18, the optical transceiver device 20 further includes a transceiver lens 23, which is disposed at the transmitting end of the first waveguide structure 223 in the transceiver waveguide structure. In this way, the first waveguide structure 223 and the second waveguide structure 224 of each transceiver waveguide structure in the stepped waveguide chip 22 share a transceiver lens 23, that is, the transmitting optical path and the receiving optical path use the same optical path, which reduces the hardware configuration of the laser radar and reduces the cost of the laser radar.

In some embodiments, as shown in FIG. 19 and FIG. 20 , the transceiver lens 23 satisfies a first preset condition, which is:

The intersection of the first straight line L1 in the first direction and the second straight line L2 in the second direction is located on the optical axis where the center of the transceiver lens 23 is located, wherein the first straight line L1 is a straight line where any two midpoints of the first connecting line are located, the first connecting line is a connecting line between the top of the first waveguide structure 223 close to the upper surface of the step waveguide chip 22 and the bottom of the first waveguide structure 223 close to the lower surface of the step waveguide chip 22, the second straight line L2 is a straight line where any two midpoints of the second connecting line are located, and the second connecting line is a connecting line between the side of the first waveguide structure 223 close to one end of the step base 21 and the side of the first waveguide structure 223 close to the other end of the step base 21. The first waveguide structure 223 is a waveguide structure for emitting laser. The echo light spots with different lag angles reflected by the emitted detection laser upon encountering the target are distributed around the first waveguide structure 223. The center of the transceiver lens 23 coincides with the center position of each first waveguide structure 223 of the step waveguide chip 22, which is beneficial for the transceiver lens 23 to evenly distribute the echo light spots with different lag angles reflected by the emitted detection laser upon encountering the target around the first waveguide structure 223, as shown in FIGS. 13 and 14 , which facilitates the second waveguide structure 224 on one or both sides of the same plane as the first waveguide structure 223 to receive the echo with a lag angle in the horizontal direction relative to the target, and also facilitates the second waveguide structure 224 distributed above or below the first waveguide structure 223 in the second direction to receive the echo with a lag angle in the vertical direction relative to the target, thereby improving the overall echo receiving efficiency of the laser radar and improving the detection performance of the laser radar.

In one embodiment, the transceiver lens 23 also satisfies a second preset condition, which is:

L = f;

Wherein, L is the lens distance, which is the vertical distance between the end face of the transmitting end of the first waveguide structure 223 in the transceiver waveguide structure and the center of the transceiver lens 23, and the transceiver lens 23 at the lens distance is used to receive the echoes of the first target distance and the second target distance;

f is the focal length of the transceiver lens 23. Optionally, the first target distance is set to be ≦100m, the second target distance is set to be >100m, and f≧1mm; preferably, the focal length f can be set to any one of 18mm, 20mm, 30mm, 50mm, or 100mm; preferably, the width of the first planar waveguide chip 221 or the second planar waveguide chip 222 is less than or equal to 2mm, and the diameter of the transceiver lens 23 is less than or equal to 40mm. The specific parameter setting is not limited to the above range, and is set according to the detection requirements of the laser radar during actual implementation. Optionally, the transceiver lens 23 can be a plurality of transceiver lens groups, and the lens distance L of the transceiver lens group 23 is set to be f.

When the target is located at a close distance within the first target distance, the interval time between the laser emission and the echo generated by the target reflection of the laser radar is short, and the angle of rotation of the galvanometer during this time is small, so the hysteresis angle of the galvanometer is small, and the hysteresis angle of the echo after reflection from the close-range target is small when returning along the reverse optical path of the laser emission optical path, and the echo light intensity reflected from the close-range target meets the energy threshold requirement of the detector, and the echo is received by the second waveguide structure 224 next to the first waveguide structure 223, thereby improving the efficiency of receiving the echo, thereby improving the ranging performance of the target within the first target distance, and improving the detection capability of the target within the first target distance.

When the target is at a long distance within the second target distance, since the distance between the long-distance target and the laser radar is greater than that between the short-distance target and the long-distance target, the signal strength of the echo reflected by the long-distance target is lower than that of the echo reflected by the short-distance target within the first target distance, so the installation position of the transceiver lens 23 is set at the focusing position, and the imaging distance of the echo reflected by the long-distance target is the focal length in order to enhance the signal energy intensity of the echo. At the same time, since the distance between the long-distance target and the laser radar is greater than the first target distance and is within the second target distance, the time from the output of the detection laser to the reflection after encountering the long-distance target and returning is relatively longer than the time for the short-distance target to return, so the hysteresis angle of the galvanometer is larger, so that the optical path of the echo after the reflection of the long-distance target and the optical path of the laser emission have a large hysteresis angle. The echo reflected by the hysteresis angle galvanometer is imaged on the left, right, top or bottom of the first waveguide structure 223 after passing through the transceiver lens 23. The installation position of the transceiver lens 23 is set at the focusing position, which is conducive to the echo being received by the second waveguide structure 224, thereby improving the echo reception efficiency and improving the laser radar's detection capability for long-distance targets within the second target distance.

In one embodiment, as shown in FIG. 9 , the focal length f is obtained based on an interval angle calculation formula, which is:

Wherein, d is a third spacing d3, and the third spacing d3 is a spacing between adjacent first waveguide structures 223 of a plurality of first waveguide structures 223 of a first planar waveguide chip 221 and a plurality of first waveguide structures 223 of a second planar waveguide chip 222 that are staggered in the second direction;

θ is an interval angle, which is an angular interval between adjacent lasers emitted by the multiple first waveguide structures 223 of the first planar waveguide chip 221 and the multiple first waveguide structures 223 of the second planar waveguide chip 222 staggered in the second direction after passing through the transceiver lens 23;

f is the focal length of the transceiver lens 23 , and preferably, f≧1 mm.

The interval angle θ is the angular interval between adjacent lasers after the laser emitted by the first waveguide structure 223 passes through the lens 23, also known as the interval angle of the scan line. When the focal length of the transceiver lens 23 is a fixed value, the smaller the third spacing d3 is, the smaller the interval angle θ is. The smaller the interval angle, the denser the laser scan lines emitted by the laser radar, the more echoes reflected by the target, the more dense point cloud detection information of the target can be obtained, the higher the resolution of the target, and the stronger the laser radar's detection capability of the target. However, the denser the laser scan lines, the greater the output power of the laser radar, and the higher the requirements for the echo signal processing capability. In this embodiment, preferably, θ≧0.05°; further, θ≧0.2° can also be set. In this embodiment, the interval angle θ is not specifically limited, and is set specifically according to the resolution capability requirements of the laser radar.

In one embodiment, as shown in FIG9 , in the first direction, the second spacing d2 is less than or equal to one tenth of the diameter of the transceiver lens 23, and the second spacing d2 is the vertical distance between the mutually adjacent sides of the transceiver waveguide structure of the first planar waveguide chip 221 and the transceiver waveguide structure of the second planar waveguide chip 222. If the second spacing d2 is less than or equal to one tenth of the diameter of the transceiver lens 23, the transceiver waveguide structure of the first planar waveguide chip 221 and the transceiver waveguide structure of the second planar waveguide chip 222 are closer to each other, which is beneficial for the second waveguide structure 224 of the first planar waveguide chip 221 and the second waveguide structure 224 of the second planar waveguide chip 222 to receive the echo with a hysteresis angle around the first waveguide structure 223, thereby improving the overall reception efficiency of the echo and enhancing the detection capability of the laser radar.

The laser radar of the prior art needs to use a free-space optical circulator, but the free-space optical circulator is expensive. The laser radar of the embodiment of the present application uses an optical transceiver 20 based on a planar waveguide chip, which does not require a free-space circulator, thereby saving the cost of the laser radar.

Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

A first aspect of an embodiment of the present application provides an optical transceiver based on a planar waveguide chip. When a laser radar with a galvanometer scans a target, since the echo reflected back by the target has a lag angle in two dimensional directions corresponding to the first axis and the second axis of the galvanometer, an optical transceiver with a planar waveguide chip for receiving and outputting echoes is arranged in two dimensional directions corresponding to the two axes. Echoes with lag angles in two dimensional directions corresponding to the first axis and the second axis of the galvanometer are received simultaneously, thereby improving the overall echo receiving efficiency of the laser radar in the vertical and horizontal directions relative to the target, improving the resolution in these two directions, and thereby improving the detection performance of the laser radar.

For a scanning module including a one-dimensional MEMS galvanometer or a mechanical galvanometer, this embodiment provides an optical transceiver device of a planar waveguide chip for receiving and outputting echoes in a direction corresponding to at least one axis of the galvanometer, thereby simultaneously receiving echoes with a hysteresis angle in a direction corresponding to at least one axis of the galvanometer, and also improving the overall echo reception efficiency of the laser radar in two directions, the vertical direction and the horizontal direction relative to the target, thereby improving the resolution in these two directions, and further improving the detection performance of the laser radar. Therefore, the optical transceiver device based on the planar waveguide chip of this embodiment is applied to a scanning module including a one-dimensional MEMS galvanometer or a mechanical galvanometer, which can not only improve the reception efficiency of echoes with a hysteresis angle in the direction corresponding to any axis, but also improve the angular resolution in the vertical direction relative to the target, thereby improving the detection performance of the laser radar.

A second aspect of an embodiment of the present application provides a laser radar, comprising a laser emission module 10, a scanning module 30, a detection module 40, a signal processing module 50, and an optical transceiver 20 as described in any one of the contents of the first aspect.

The laser emission module 10 is used to output laser, split the laser beam, obtain N laser beams and M local oscillator beams, and output N laser beams and M local oscillator beams respectively, wherein M and N are both positive integers, N≧2, M≧2. Optionally, the emission light power of the laser emission module 10 is greater than or equal to 100mW, which is convenient for achieving detection at a longer distance.

The optical transceiver 20 is used to access each laser in the N channels and output each laser respectively.

The scanning module 30 is used to receive various laser beams and emit the various laser beams to the target for scanning. The scanning module is also used to receive the echo reflected by the target and then output the echo.

The optical transceiver 20 is also used to receive the echo and output the echo.

The detection module 40 has M detection units, each detection unit is connected to one of the M laser paths, and each detection unit is used to connect the echo and mix the echo with the connected laser path to obtain corresponding beat frequency electrical signals.

The signal processing module 50 is used to receive each beat frequency electrical signal and process it to obtain the detection information of the target.

By adopting the optical transceiver of any one of the contents of the first aspect above, the overall echo receiving efficiency of the laser radar is improved, and the problem of partial echo signal loss caused by the laser radar having a detection light angle lag effect in the horizontal and vertical directions relative to the target is effectively improved, thereby improving the ranging performance and resolution performance of the laser radar, and further improving the detection capability of the target.

Optionally, the input end of the detection module 40 is coupled with the output end of the second waveguide structure 224 in the optical transceiver device 20; the output end of the detection module 40 is coupled with the input end of the signal processing module 50, wherein the detection module 40 is coupled with the first planar waveguide chip 221 or the second planar waveguide chip 222 in the optical transceiver device 20, and the coupling method between the two includes at least one of direct end face packaging coupling, optical fiber coupling or spatial optical coupling, thereby improving the integration of the laser radar.

Optionally, the detection module 40 is provided with a photodetector and a local oscillator light input optical path, and the echo signal and the local oscillator light are coherently detected and mixed on the photodetector. The photodetector is a photodetector that senses various wavelengths, such as a laser with a wavelength of at least one of 905nm, 1000nm or 1550nm.

Optionally, the detection information includes at least one of three-dimensional distance information, speed information, orientation information, shape information and reflectivity information.

A third aspect of the embodiment of the present application provides a method for manufacturing an optical transceiver 20 based on a planar waveguide chip, comprising:

Providing a stepped substrate 21, wherein the upper surface of the stepped substrate 21 includes a first stepped upper surface and a second stepped upper surface;

A first planar waveguide chip 221 is formed on the upper surface of the first step, and a second planar waveguide chip 222 is formed on the upper surface of the second step. The first planar waveguide chip 221 and the second planar waveguide chip 222 are both used for emitting laser light and receiving and outputting echoes.

It can be understood that the beneficial effects of the second and third aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims (12)

1. An optical transceiver based on a planar waveguide chip, applied to a laser radar, comprising:

a step substrate, an upper surface of the step substrate comprising a first step upper surface and a second step upper surface, the first step upper surface and the second step upper surface being in planes parallel to a bottom surface of the step substrate and having different heights;

The ladder waveguide chip is arranged on the ladder substrate and comprises a first plane waveguide chip and a second plane waveguide chip, wherein the first plane waveguide chip and the second plane waveguide chip are both used for emitting laser and receiving echoes and outputting the echoes, the first plane waveguide chip is arranged on the first ladder upper surface of the ladder substrate, and the second plane waveguide chip is arranged on the second ladder upper surface of the ladder substrate;

The first planar waveguide chip and the second planar waveguide chip respectively comprise a plurality of transceiving waveguide structures, the transceiving waveguide structures in the first planar waveguide chip and the second planar waveguide chip are arranged at intervals in parallel along a second direction and extend from one end to the other end of the stepped waveguide chip along a third direction, wherein the first direction is a transverse direction parallel to the bottom surface of the stepped substrate and different in height along the upper surface of the stepped substrate, the second direction is a direction perpendicular to the bottom surface of the stepped substrate, the third direction is a longitudinal direction parallel to the bottom surface of the stepped substrate and extending along the same height as the upper surface of the stepped substrate, and the second direction is perpendicular to the first direction and the third direction;

in the second direction, the plurality of transceiver waveguide structures of the first planar waveguide chip and the plurality of transceiver waveguide structures of the second planar waveguide chip are arranged in a staggered manner.

2. The optical transceiver of claim 1, wherein,

In a first direction, the first planar waveguide chip is in contact with the second planar waveguide chip.

3. The optical transceiver of claim 1, wherein,

The receiving-transmitting waveguide structure comprises a first waveguide structure for transmitting the laser and at least one second waveguide structure for receiving the echo and outputting the echo, and the second waveguide structure is arranged on at least one side of the first waveguide structure.

4. The optical transceiver device of claim 3, wherein,

The first waveguide structure is a single-mode waveguide structure;

the second waveguide structure is any one of a multimode-to-single mode waveguide structure, a large-mode-to-single mode waveguide structure, a few-mode-to-single mode waveguide structure and a single mode waveguide structure.

5. The optical transceiver device according to any one of claim 3 or 4, wherein,

At least one second waveguide structure in the same transceiver waveguide structure has a preset inclination angle relative to the first waveguide structure.

6. The optical transceiver device of claim 5, wherein,

The preset inclination angle is 0.1 degree.

7. The optical transceiver device of claim 6, wherein,

The first interval between the emitting end of the first waveguide structure and the input end of the adjacent second waveguide structure is K, wherein K is 0.1 xW and 0.2 xW, and W is the waveguide width of the single-mode waveguide structure in the first waveguide structure or the second waveguide structure.

8. The optical transceiver of claim 1, wherein,

In the second direction, a first interval is greater than or equal to 50 μm, and the first interval is a vertical distance between adjacent transceiving waveguide structures in the first planar waveguide chip or the second planar waveguide chip.

9. The optical transceiver device of claim 3, wherein,

In the first direction, the first planar waveguide chip and the second planar waveguide chip each include a plurality of transceiving waveguide structures arranged in an array.

10. The optical transceiver device of claim 3, wherein,

The optical transceiver further comprises a transceiver lens, and the transceiver lens is arranged at the transmitting end of the first waveguide structure in the transceiver waveguide structure.

11. The optical transceiver of claim 10, wherein,

In the first direction, a second pitch is less than or equal to one tenth of the diameter of the transceiver lens, and the second pitch is a vertical distance between the transceiver waveguide structure of the first planar waveguide chip and a side surface of the transceiver waveguide structure of the second planar waveguide chip, which is close to each other.

12. A lidar comprising a laser emitting module, a scanning module, a detection module, a signal processing module, and the optical transceiver device of any of claims 1 to 11;

The laser emission module is used for outputting laser, splitting the laser to obtain N paths of laser and M paths of local oscillation light, and respectively outputting N paths of laser and M paths of local oscillation light, wherein M, N are positive integers, N is not less than 2, and M is not less than 2;

the optical transceiver is used for accessing each path of laser in the N paths and outputting each path of laser respectively;

The scanning module is used for accessing each path of laser and emitting each path of laser to a target for scanning, and is also used for receiving echoes reflected by the target and outputting the echoes;

the optical transceiver is also used for accessing the echo and outputting the echo;

The detection module is provided with M detection units, each detection unit is connected with one path of laser in M paths, and is used for connecting the echo and mixing the echo with one path of local oscillation light to obtain a corresponding beat frequency electric signal;

the signal processing module is used for accessing each beat frequency electric signal and processing the beat frequency electric signals to obtain detection information of the target.