Optical transceiver assembly for lidar, lidar, and terminal device

Abstract

An optical transceiver assembly (100) for a lidar, a lidar, and a terminal device. The optical transceiver assembly (100) comprises a transmitting end (110) and a receiving end (120). The transmitting end (110) comprises a transmitter (111) and a transmitting lens (112). The transmitter (111) comprises a laser. The transmitter (111) is used for emitting a first light beam. The transmitting lens (112) is used for shaping the first light beam and guiding the first light beam to an external field of view. The receiving end (120) comprises a receiving lens (122) and a receiver (121). The receiving end (120) is used for transmitting to the receiver (121) an echo generated after the first light beam is reflected by an object. The receiver (121) comprises a detector. The receiver (121) is used for receiving the echo and generating an electrical signal. The ratio of the image height of the transmitting lens (112) to the receiving lens (122) at a preset field of view angle is within a first threshold interval, such that the degree of overlapping of the field of view of the laser and the field of view of the detector is greater than a second set threshold.

Description

Optical transceiver components, laser radars and terminal equipment for laser radars Technical Field

[0001] The present disclosure relates to the field of laser radar, and more specifically to an optical transceiver assembly for laser radar, a laser radar, and a terminal device. Background Art

[0002] LiDAR (LiDAR) is a radar system that uses laser beams to detect the position, velocity, and other characteristics of a target object. It is an advanced detection method that combines laser technology with photoelectric detection technology. Due to its high resolution, strong resistance to active interference, excellent detection performance, small size, and light weight, LiDAR is widely used in autonomous driving, transportation communications, drones, intelligent robots, resource exploration, and other fields. Summary of the Invention

[0003] According to a first aspect of the present disclosure, an optical transceiver assembly for a lidar is provided, comprising: a transmitting end, comprising: a transmitter, comprising a laser, the transmitter being configured to transmit a light beam; and a transmitting lens, being configured to shape the light beam and guide the light beam to an external field of view; a receiving end, comprising: a receiving lens, being configured to transmit an echo generated after the light beam is reflected by an object to a receiver; a receiver, comprising a plurality of detectors, the receiver being configured to receive the echo and generate an electrical signal, and a ratio of an image height of the transmitting lens to that of the receiving lens at a preset field of view angle is within a first threshold range, so that the overlap degree of the field of view of the laser and the field of view of the detector is greater than a second set threshold.

[0004] Optionally, the second set threshold is 50%, 60%, 80% or 90%.

[0005] Optionally, the field of view (FOV) of the transmitting end is greater than or equal to 140°, the field of view of the receiving end is greater than or equal to 140°, the focal length of the transmitting lens is less than or equal to 16 mm, and the focal length of the receiving lens is less than or equal to 16 mm.

[0006] Optionally, the emitting lens includes at least a first meniscus lens located on the light-emitting side, the concave surface of the first meniscus lens faces the emitter, and the first meniscus lens has a negative optical power.

[0007] Optionally, the receiving lens includes at least a second meniscus lens located on the light incident side, the concave surface of the second meniscus lens faces the receiver, and the second meniscus lens has a negative optical power.

[0008] Optionally, at least one of the horizontal field of view angle or the vertical field of view angle of the transmitting end is less than 180°, and at least one of the horizontal field of view angle or the vertical field of view angle of the receiving end is less than 180°.

[0009] Optionally, the horizontal field of view angle of the transmitting end is greater than 180°, the horizontal field of view angle of the receiving end is greater than 180°, and the transmitting lens and the receiving lens are arranged vertically.

[0010] Optionally, the vertical field of view angle of the transmitting end is greater than 180°, the vertical field of view angle of the receiving end is greater than 180°, and the transmitting lens and the receiving lens are arranged horizontally.

[0011] Optionally, the degree of distortion of the transmitting lens and the receiving lens at the edge of the field of view is greater than the degree of distortion at the center of the field of view.

[0012] Optionally, the field of view angle of the transmitting end is greater than or equal to 150°, the field of view angle of the receiving end is greater than or equal to 150°, and the focal length of the transmitting lens is less than or equal to 10 mm, and the focal length of the receiving lens is less than or equal to 10 mm.

[0013] Optionally, the focal length of the transmitting lens is smaller than the focal length of the receiving lens.

[0014] Optionally, the size of the transmitter is smaller than the size of the receiver.

[0015] According to a second aspect of the present disclosure, there is provided an optical transceiver assembly for a lidar, comprising: a transmitter including a laser, the transmitter being configured to transmit a light beam; a receiver including a detector, the receiver being configured to receive an echo after the light beam is reflected by an object and generate an electrical signal; a spectrometer configured to guide and separate the light beam and the echo; a transceiver lens configured to shape the light beam and guide the light beam to an external field of view, and transmit the echo to the receiver; a ratio of an image height of an emitting light path to an image height of a receiving light path of the transceiver lens at a preset field of view angle is within a first threshold range, so that the overlap degree of the field of view of the laser and the field of view of the detector is greater than a second set threshold.

[0016] Optionally, the field of view angle of the optical transceiver assembly is greater than or equal to 140°, and the focal length of the transceiver lens is less than or equal to 16 mm.

[0017] Optionally, the transceiver lens includes at least a meniscus lens, the concave surface of the meniscus lens faces the incident direction of the light beam, and the convex surface of the meniscus lens faces the incident direction of the echo.

[0018] Optionally, the field of view angle of the optical transceiver assembly is greater than or equal to 150°, and the focal length of the transceiver lens is less than or equal to 10 mm.

[0019] According to a third aspect of the present disclosure, an optical transceiver assembly for a lidar is provided, comprising: a transmitting end having: a transmitter comprising a laser array configured to transmit a light beam; and a transmitting lens; a receiving end having: a receiving lens; and a receiver comprising a detector array configured to receive echoes, wherein the angular resolution of a first area of ​​the field of view of the optical transceiver assembly is different from the angular resolution of a second area of ​​the field of view of the optical transceiver assembly, and at least one of the transmitting lens and the receiving lens comprises a negative meniscus lens.

[0020] Optionally, the second area is closer to the edge of the field of view of the optical transceiver assembly than the first area.

[0021] Optionally, the transmitting chip and the receiving chip are arranged on the same circuit board.

[0022] Optionally, the emitting lens includes a first negative meniscus lens, and the laser array includes a plurality of lasers that are evenly distributed.

[0023] Optionally, the concave surface of the first negative meniscus lens faces the incident direction of the light beam.

[0024] Optionally, the detector array includes a plurality of detectors non-uniformly distributed along the first direction.

[0025] Optionally, the multiple detectors are non-uniformly distributed along a second direction, and the second direction is different from the first direction.

[0026] Optionally, the detector density of the third region of the detector array is greater than the detector density of the fourth region of the detector array.

[0027] Optionally, the fourth region is closer to the edge of the detector array than the third region.

[0028] Optionally, the receiving lens includes a second negative meniscus lens, and the detector array includes a plurality of evenly distributed detectors.

[0029] Optionally, the convex surface of the second negative meniscus lens faces the incident direction of the echo.

[0030] Optionally, the laser array includes a plurality of lasers non-uniformly distributed along the first direction.

[0031] Optionally, the plurality of lasers are non-uniformly distributed along a second direction, and the second direction is different from the first direction.

[0032] Optionally, the laser density in the fifth region of the laser array is greater than the laser density in the sixth region of the laser array.

[0033] Optionally, the sixth region is closer to the edge of the detector array than the fifth region.

[0034] Optionally, a light spot emitted by a laser in the laser array at least partially overlaps with a field of view of at least one detector in the detector array.

[0035] Optionally, the transmitting lens or the receiving lens includes at least one of the following: a wide-angle lens or a fisheye lens.

[0036] Optionally, the optical transceiver assembly further includes a light homogenizer arranged on the optical path of the transmitting end.

[0037] According to a fourth aspect of the present disclosure, a laser radar is provided, comprising: the optical transceiver assembly as described above; and a controller configured to: control the transmitter to emit the light beam; and determine at least one of the distance and reflectivity of the object based at least on the echo received by the receiver.

[0038] According to a fifth aspect of the present disclosure, a terminal device is provided, comprising the laser radar as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The present disclosure may be better understood by describing exemplary embodiments of the present disclosure with reference to the accompanying drawings.

[0040] FIG1 illustrates a schematic block diagram of an exemplary optical transceiver assembly for a lidar consistent with some embodiments of the present disclosure.

[0041] FIG2 illustrates several examples of uniformly distributed laser arrays consistent with some embodiments of the present disclosure.

[0042] FIG3 illustrates several examples of uniformly distributed detector arrays consistent with some embodiments of the present disclosure.

[0043] FIG4 illustrates an example of a transmitter and receiver consistent with some embodiments of the present disclosure.

[0044] FIG5 illustrates another example of a transmitter and receiver consistent with some embodiments of the present disclosure.

[0045] FIG6 illustrates yet another example of a transmitter and receiver consistent with some embodiments of the present disclosure.

[0046] FIG7 shows a schematic diagram of a vertical arrangement of a transmitting lens and a receiving lens consistent with some embodiments of the present disclosure.

[0047] FIG8 shows a schematic diagram of a horizontal arrangement of a transmitting lens and a receiving lens consistent with some embodiments of the present disclosure.

[0048] FIG9 shows a schematic diagram of a transmitting end including a meniscus lens, consistent with some embodiments of the present disclosure.

[0049] FIG. 10 shows a schematic diagram of a receiving end including a meniscus lens, consistent with some embodiments of the present disclosure.

[0050] FIG11 shows a schematic diagram of an exemplary optical transceiver assembly for a lidar consistent with some embodiments of the present disclosure.

[0051] 12 to 14 respectively illustrate several examples of different focal lengths at the transmitting end and the receiving end of an exemplary optical transceiver assembly consistent with some embodiments of the present disclosure.

[0052] FIG15 shows a schematic diagram of an exemplary optical transceiver assembly for a lidar consistent with some embodiments of the present disclosure.

[0053] FIG. 16 shows an exemplary schematic diagram of an optical transceiver assembly having non-uniform angular resolution.

[0054] 17 illustrates a schematic diagram of a transmitter including a negative meniscus lens, consistent with some embodiments of the present disclosure.

[0055] 18 illustrates a schematic diagram of a receiver including a negative meniscus lens, consistent with some embodiments of the present disclosure.

[0056] FIG19 shows a schematic diagram of a transmitting chip and a receiving chip being arranged on the same circuit board in accordance with some embodiments of the present disclosure.

[0057] 20A-20C illustrate examples of non-uniformly distributed detector arrays consistent with some embodiments of the present disclosure.

[0058] 21A-21C illustrate examples of non-uniformly distributed laser arrays consistent with some embodiments of the present disclosure.

[0059] FIG22 shows a schematic block diagram of an exemplary lidar consistent with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0060] Some embodiments of the present disclosure will be described below. It should be noted that in the description of these embodiments, in order to provide a concise description, this specification cannot provide a detailed description of all the features of the actual embodiments. It should be understood that in the actual implementation of any embodiment, just as in the process of any engineering project or design project, in order to achieve the developer's goals and to meet system-related or business-related restrictions, various decisions are often made, and this will also change from one embodiment to another. In addition, it is also understandable that although the efforts made in this development process may be complex and lengthy, for ordinary technicians in the field related to the contents disclosed by this disclosure, some changes in design, manufacturing or production based on the technical contents disclosed in this disclosure are just conventional technical means and should not be understood as the contents of this disclosure being insufficient.

[0061] Unless otherwise defined, the technical or scientific terms used in the claims and description shall have the usual meaning understood by persons of ordinary skill in the technical field to which the present disclosure belongs. The words "first", "second" and similar terms used in the patent application description and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "one" or "a" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprising" mean that the elements or objects appearing before "include" or "comprising" cover the elements or objects listed after "include" or "comprising" and their equivalents, and do not exclude other elements or objects. Words such as "connected" or "connected" and similar terms are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0062] In the present disclosure, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form new technical solutions. In the present disclosure, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form new technical solutions.

[0063] In the present disclosure, the terms "or" and "and / or" describe the association relationship between related objects and represent a non-exclusive inclusion. For example, "A and / or B" and "A or B" may include: only "A" exists, only "B" exists, and "A" and "B" exist at the same time, where "A" and "B" can be singular or plural. For another example, "A, B and / or C" and "A, B or C" may include: only "A" exists, only "B" exists, only "C" exists, "A" and "B" exist at the same time, "A" and "C" exist at the same time, "B" and "C" exist at the same time, and "A", "B" and "C" exist at the same time, where "A", "B" and "C" can be singular or plural. In addition, the symbol " / " in the present disclosure indicates that there is an "or" relationship between the related objects before and after the symbol. In the present disclosure, the term "at least one A or B" has the same meaning as the above-mentioned "A or B". The term "at least one A, B or C" has the same meaning as the above-mentioned "A, B or C".

[0064] LiDAR (light detection and ranging) is a radar system that uses a laser beam to detect the position, speed and other characteristic quantities of an object. LiDAR, also known as laser radar or LADAR, emits a light beam (for example, a laser beam) to an object, and then compares and processes the received reflected light (echo) reflected from the object with the emitted light to obtain information about the object. For example, parameters such as the distance, direction, height, speed, attitude, and shape of the object. LiDAR may include a transmitting end and a receiving end. The transmitting end collimates and shapes the output light of the laser through a transmitting optical system and projects it into the field of view. The receiving end receives the echo signal reflected by the output light from the object through a receiving optical system and a detector. The laser can be deployed on a transmitting circuit board or a transmitting chip, and the detector can be deployed on a receiving circuit board or a receiving chip. In the present disclosure, LiDAR can be replaced by other active detection devices that measure the position, speed and other information of an object by emitting electromagnetic waves to the object and receiving electromagnetic waves reflected from the object.

[0065] In the LiDAR technology solution, a larger FOV coverage can be achieved by using rotation (motor), scanning (galvanometer, rotating mirror), multi-lens stitching, etc. The above solution will increase the complexity and cost of the solution. In some embodiments, a lens that expands the field of view can be used to increase the FOV of the LiDAR. Such a lens will inevitably have distortion, resulting in a mismatch between the LiDAR's transmission and reception (for example, the echo formed by the reflection of part of the light emitted by the transmitter by the object cannot return to the corresponding receiver). For LiDARs that use highly integrated transmitter chips and highly integrated receiver chips, the evenly distributed transmitters and receivers are prone to mismatch between transmission and reception due to lens distortion.

[0066] The present disclosure proposes an optical transceiver assembly for a laser radar, comprising a transmitting end and a receiving end. The transmitting end includes a transmitter and a transmitting lens. The transmitter includes a laser. The transmitter is configured to emit a first light beam. The transmitting lens is configured to shape the first light beam and direct it to an external field of view. The receiving end includes a receiving lens and a receiver. The receiving end is configured to transmit an echo generated by reflection of the first light beam from an object to a receiver. The receiver includes a detector. The receiver is configured to receive the echo and generate an electrical signal. The ratio of the image heights of the transmitting lens and the receiving lens at a preset field of view angle is within a first threshold range, such that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold. The multiple lasers in the present disclosure may include one or more of vertical-cavity surface-emitting lasers (VCSELs), edge-emitting lasers (EELs), distributed feedback lasers (DFBs), fiber lasers, or similar devices. The transmitter in the present disclosure may also include a laser transmission circuit, etc. The multiple detectors in the present disclosure may include one or more single photon avalanche diodes (SPADs), avalanche photodiodes (APDs), silicon photomultipliers (SiPMs), or similar devices, and the receivers in the present disclosure may also include light detection circuits, etc.

[0067] In the disclosed optical transceiver assembly for a laser radar, the ratio of the image heights of the transmitting lens and the receiving lens at a preset field of view angle is within a first threshold range, such that the overlap between the laser's field of view and the detector's field of view is greater than a second set threshold. When the transmitter utilizes uniformly distributed lasers and the receiver utilizes uniformly distributed detectors, transceiver alignment can be achieved at the preset field of view angle (for example, the echo formed by the laser's light reflected by an object can reach the detector).

[0068] See Figures 1 to 3. Figure 1 illustrates a schematic block diagram of an exemplary optical transceiver assembly for a lidar consistent with some embodiments of the present disclosure. Figure 2 illustrates several examples of uniformly distributed laser arrays consistent with some embodiments of the present disclosure. Figure 3 illustrates several examples of uniformly distributed detector arrays consistent with some embodiments of the present disclosure.

[0069] The optical transceiver assembly 100 for a lidar includes a transmitter 110 and a receiver 120. Transmitter 110 includes a transmitter 111 and a transmitting lens 112. Transmitter 111 includes a laser that generates a light beam. Transmitter lens 112 shapes the light beam and directs it into an external field of view. The spatial detection range of the light beam shaped and directed by transmitting lens 112 forms the transmitting field of view of transmitter 110. Receiver 120 includes a receiver 121 and a receiving lens 122. Receiving lens 122 transmits the echo generated by the light beam after reflection from an object to receiver 121. Receiver 121 includes a detector that receives the echo and generates an electrical signal. The spatial range that receiver 121 can detect through receiving lens 122 forms the receiving field of view of receiver 120. The receiving field of view and the transmitting field of view should correspond to each other. For example, the field of view of the laser corresponds to the field of view of the detector, so that the echo generated by at least part of the light beam emitted by the laser after reflection from an object in space can reach the detector.

[0070] In some embodiments of the present application, the transmitter 111 may include a laser array (as shown in FIG2 ), and the receiver 121 may include a detector array (as shown in FIG3 ). The laser array may be a two-dimensionally arranged laser array, or a one-dimensionally arranged laser array. The individual lasers in the laser array may emit light in a time-sharing manner (for example, in sequence), or they may emit light simultaneously. The light beams emitted by the individual lasers in the laser array are collimated and guided by the transmitting lens 112 to form a FOV. Within the FOV range, if an object that can reflect light appears, the echo formed after the light beam is reflected by the object is received by the receiving lens 122, and is converged on the corresponding detector of the detector array in the corresponding field of view through the receiving lens 122, forming the entire detection circuit of the lidar. It should be noted that the correspondence between such lasers and detectors can be that the light spot emitted by the laser 11 corresponds to the FOV of a single detector 21 (as shown in FIG4 ), or that the light spot emitted by the laser 11 corresponds to the FOV of multiple detectors 21 (as shown in FIG5 or 6 ), or that the light spots emitted by multiple lasers correspond to the FOV of one detector, or that the light spots emitted by multiple lasers correspond to the FOV of multiple detectors.

[0071] In an embodiment of the present disclosure, the transmitting lens 112 can expand the transmitting field of view of the transmitter 111. The receiving lens 122 can expand the receiving field of view of the receiver 121. The transmitting lens 112 and the receiving lens 122 that can expand the field of view to increase the field of view angle of the optical transceiver assembly 100 will inevitably bring about pincushion distortion or barrel distortion. Assuming that the distortion of the transmitting lens 112 and the receiving lens 122 do not match (for example, one of the lenses has distortion and the other lens has no distortion), it may cause the echo formed by the light beam emitted by the laser being reflected by the object to be unable to return to the detector, that is, a mismatch occurs between the light-emitting surface and the photosensitive surface. As one of the solutions to this problem, the position of the laser or detector can be adjusted according to the distortion to ensure the correspondence between transmission and reception. For example, assuming that the transmitter 111 is a uniformly distributed laser array and the transmitting lens 112 will bring optical distortion, while the distortion of the receiving lens 122 is very different from the distortion of the transmitting lens 112 or there is no distortion, then the detector array on the receiver 121 can be designed to be non-uniformly distributed according to the specific distortion curves of the two lenses, thereby compensating for the mismatch between the light-emitting surface and the photosensitive surface caused by the lens distortion. With the improvement of the integration of optoelectronic devices, such as the chipization of the transceiver, the transmitter / receiver devices have become integrated devices, and the integrated device can include uniformly distributed transmitter / receiver devices. For IC design, uniformly distributed lasers / detectors and processing circuits are more economical and less complex to design, so other ways are needed to solve this problem.

[0072] In some embodiments of the present disclosure, the transmitting lens 112 and the receiving lens 122 can be designed to have the same or similar distortion curves, that is, the same or similar F-theta (f-θ) distortion. Having the same f-θ distortion for the transmitting lens 112 and the receiving lens 122 means that the ratio of the image height of the transmitting lens to the image height of the receiving lens at a preset field of view angle is the same or similar and falls within a first preset range. In this way, both the transmitter 111 and the receiver 121 can include evenly distributed optoelectronic devices, and the field of view of the laser and the field of view of the detector can substantially overlap. For detection, it is sufficient that the field of view of the laser and the field of view of the detector overlap, and the overlap exceeds a preset threshold. In this case, the transmitting lens 112 and the receiving lens 122 do not need to have exactly the same f-θ distortion; rather, they only need to be similar. Having similar f-θ distortion for the transmitting lens 112 and the receiving lens 122 means that the ratio of their image heights at the preset field of view angle falls within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector can exceed a second preset threshold. As an example, the second set threshold may be between 50% and 90%, such as 50%, 60%, 80% or 90%.The value of the first threshold interval is related to the focal length of the transmitting lens and the receiving lens.

[0073] In some embodiments, the ratio of the image heights of the transmitting lens 112 and the receiving lens 122 at a preset field of view angle is within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold.

[0074] In some embodiments, the ratio of the image heights of the transmitting lens 112 and the receiving lens 122 at multiple preset field of view angles is within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold.

[0075] In some embodiments, the ratio of the image heights of the transmitting lens 112 and the receiving lens 122 at each preset field of view angle is within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold.

[0076] In some embodiments of the present disclosure, the focal lengths of the transmitting lens 112 and the receiving lens 122 may be the same or different, and this may be adjusted according to the size of the transmitter 111 and the receiver 121, as long as the transmitting lens 112 and the receiving lens 122 can adopt the same or similar f-θ distortion so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold. For example, the transmitting lens 112 and the receiving lens 122 may adopt the same design, or for an existing transmitting lens (or receiving lens), the receiving lens (or transmitting lens) may be redesigned and the f-θ distortion curve of the lens may be adjusted by changing the material, curvature, thickness, and spacing of the lenses in the lens so that it is the same or similar to the f-θ distortion curve of the transmitting lens (or receiving lens).

[0077] In some embodiments of the present disclosure, the optical transceiver assembly 100 may employ a uniformly distributed laser array and a uniformly distributed detector array. The sizes of the laser array and the detector array may be the same or different. The image height h of the transmitting lens 112 and the receiving lens 122 is related to the field of view angle θ, the focal length f, and the f-θ distortion curve. Assuming that the transmitter 111 (or receiver 121) includes uniformly distributed lasers (or detectors) and the design of the transmitting lens 112 (or receiving lens 122) is completed for the desired transmitting field of view (or receiving field of view), the focal length and distortion curve of the transmitting lens 112 (or receiving lens 122) are fixed, and the image height of the corresponding transmitting lens 112 (or receiving lens 122) under the preset field of view angle θ is determined. In this case, in order to align the field of view of the laser with the field of view of the corresponding detector, for example, the laser beam emitted by the laser passes through the transmitting lens 112 corresponding to a certain field of view angle θ0, and the echo of the beam after being reflected by the object needs to pass through the receiving lens 122 to reach the corresponding detector. In order to achieve this, it is necessary to design the receiving lens 122 (or transmitting lens 112) so that the image height of the laser beam (at an angle of θ0) at the receiving lens 122 (or transmitting lens 112) corresponds to the size of the detector (or laser). In order for the field of view of the laser to be aligned with the field of view of the detector, the ratio of the image heights of the transmitting lens 112 and the receiving lens 122 at a preset field of view angle needs to be within a first threshold range. It should be noted that when the ratio of the image height of the transmitting lens 112 to the image height of the receiving lens 122 is equal to the ratio of the size of the laser to the size of the detector, the laser and the detector can be exactly aligned, but since the laser and the detector both have a certain size, incomplete alignment is also acceptable. Therefore, setting the ratio of the image heights of the transmitting lens 112 and the receiving lens 122 at a preset field of view angle within the first threshold range can make the overlap of the field of view of the laser and the field of view of the detector greater than the second set threshold. In order to achieve the above purpose, the receiving lens 122 and the transmitting lens 112 need to have the same or similar f-θ distortion curve, so that the field of view of the laser can be aligned with the field of view of the detector when both the transmitter 111 and the receiver 121 use uniformly distributed optoelectronic devices (lasers and detectors).

[0078] In an embodiment of the present disclosure, the transmitting lens 112 can expand the transmitting field of view of the transmitter 111 so that the field of view of the transmitting end 110 is greater than or equal to 140°, and the receiving lens 122 can expand the receiving field of view of the receiver 121 so that the FOV of the receiving end 120 is greater than or equal to 140°. The focal length of the transmitting lens 112 can be less than or equal to 16 mm. The focal length of the receiving lens 122 can be less than or equal to 16 mm. Compared with the solution of using moving parts to rotate the optical transceiver assembly or using scanning devices to change the propagation direction of the light beam to achieve a larger FOV, the present disclosure uses a lens that expands the field of view to replace the moving parts or scanning devices to achieve a laser radar with an ultra-large field of view. It can expand the FOV of the laser radar while reducing the size requirements of the optoelectronic devices in the laser radar. In addition, it can also eliminate the additional costs caused by moving parts or scanning devices. It should be noted that the field of view angle of the transmitting end 110 here is greater than or equal to 140°, which means that at least one of the horizontal field of view angle and the vertical field of view angle of the transmitting end 110 is greater than or equal to 140°, and the field of view angle of the receiving end 120 here is greater than or equal to 140°, which means that at least one of the horizontal field of view angle and the vertical field of view angle of the receiving end 120 is greater than or equal to 140°.

[0079] The focal length, field of view, and device size of a transmitter (e.g., transmitter 110) and a receiver (e.g., receiver 120) can be expressed by the following formula: θ Tx =θ Rx

[0080] Among them, f Rx is the focal length of the receiving end, f Tx is the focal length of the transmitter, θ Rx is the viewing angle of the receiving end, θ Tx is the field of view of the transmitter, L Rx is the detector size, L Tx is the laser size.

[0081] According to the above formula, when the FOV is fixed, the size of the laser or detector is related to the focal length of the transmitting lens 112 or the receiving lens 122. For the receiving end, since the detector has a certain size, and in order to increase the number of point clouds in a frame of image and improve the resolution, the detector array usually includes many detectors, so the overall size of the detector array is large. If the focal length of the transmitting end is the same as that of the receiving end, the size of the laser array at the transmitting end also needs to be larger, which is not conducive to cost and yield control. Therefore, in an optional embodiment, the focal length of the transmitting lens 112 can be designed to be smaller than the focal length of the receiving lens 122, so that the size of the laser array can be reduced. In this way, the size of the transmitter 111 can be smaller than that of the receiver 112.

[0082] In some embodiments of the present disclosure, the field of view angle of the transmitting end 110 may be greater than or equal to 140° in a first direction, and may be unrestricted in a second direction different from the first direction. In other embodiments of the present disclosure, the field of view angle of the transmitting end 110 may also be greater than or equal to 140° in the second direction. As an example, the first direction and the second direction may be the horizontal direction and the vertical direction, respectively.

[0083] In some embodiments of the present disclosure, when both the horizontal and vertical fields of view of the transmitter 110 are greater than 140°, to ensure effective isolation between the transmitter and receiver, at least one of the horizontal and vertical fields of view of the transmitter 110 must be less than 180°. Similarly, when both the horizontal and vertical fields of view of the receiver 120 are greater than 140°, at least one of the horizontal and vertical fields of view of the receiver 120 must be less than 180°. If both the horizontal and vertical fields of view of the transmitter 110 and the receiver 120 exceed 180°, the transmitting lens 112 and the receiving lens 122 can be arranged vertically, as shown in FIG7 . If both the vertical fields of view of the transmitter 110 and the receiver 120 exceed 180°, the transmitting lens 112 and the receiving lens 122 can be arranged horizontally, as shown in FIG8 .

[0084] In some embodiments of the present disclosure, the transmitting lens 112 can be made of all glass or a glass-plastic hybrid design, and the number of lenses generally increases as the FOV of the lens increases. The transmitting lens 112 can include a front light group and a back light group. The front light group can expand the field of view (i.e., compress the large field of view angle of the object side to the field of view range required by an ordinary lens), and the back light group can shape (e.g., collimate) the laser beam emitted by the transmitter 111. The front light group and the back light group together provide the focal length required by the transmitting lens 112.

[0085] In order to provide better field of view compression, that is, to make the transmitting end 110 have a larger FOV, the transmitting lens 112 includes at least a first meniscus lens on the light-emitting side as a component in the front light group. The first meniscus lens can expand the transmitting field of view of the transmitter 111, as shown in Figure 9. The first meniscus lens 91 can have a negative optical power, thereby shortening the overall focal length of the transmitting lens 112. As shown in the figure, the transmitting lens 112 also includes a back light group 92, which is configured to shape (for example, collimate) the light beam emitted by the transmitter 111.

[0086] Similarly, to provide better field of view compression, that is, to enable a larger FOV at the receiving end 120, the receiving lens 122 may include at least a second meniscus lens located on the light-entry side as a component of the front light assembly. The second meniscus lens can expand the receiving field of view of the receiver 121, as shown in Figure 10. The second meniscus lens 101 can have a negative optical power, thereby shortening the overall focal length of the receiving lens 122. As shown in the figure, the transmitting lens 112 also includes a back light assembly 102, which is configured to guide the echo to the receiver 121.

[0087] The relationship between the field of view angle θ and the image height h of a distortion-free lens (focal length f) is h = f * tan(θ). The angular resolution of the field of view for a single detector size x at the center of the lens (focal length f) is α ≈ x / f. The above two formulas show that, given a given detector size, if higher angular resolution is desired (i.e., a smaller α value), a larger lens focal length f is preferred. For the same FOV, a larger f significantly increases the image height h at the edge of the field of view, which in turn increases the required device size. This increased device size translates to higher costs and reduced reliability.

[0088] As described above, the transmitting lens 112 and receiving lens 122 of the present disclosure may have f-θ distortion. By properly designing the distortion curves of the transmitting lens 112 and receiving lens 122, the degree of distortion of the transmitting lens 112 and receiving lens 122 at the edge of the field of view (corresponding to a larger field of view angle) can be greater than the degree of distortion at the center of the field of view (corresponding to a smaller field of view angle). In this way, the image height can be quickly converged at the edge of the lens, while meeting the requirements for the central field of view angular resolution and FOV size while avoiding excessive device size, thus achieving a balance between the angular resolution of the central field of view and the device size.

[0089] On the other hand, when the laser and detector are of uniform size and evenly arranged, the lens design of the present disclosure can make the distortion at the edge of the field of view larger to reduce the size of the device. Therefore, the closer the detector is to the edge of the field of view, the larger the corresponding field of view angle interval, that is, the more diluted its corresponding point cloud is. LiDAR is generally more concerned with the detection of the central field of view, so the optical transceiver assembly 100 with a larger FOV takes advantage of this and can obtain a point cloud with a large FOV and a dense central field of view and a sparse edge field of view. In this way, the angular resolution of the central area of ​​the LiDAR can be made higher, which can provide more precise target recognition and measurement for the central area.

[0090] As shown in Figure 9, the emitting lens 112 can distort the uniformly distributed laser light-emitting surface into a structure with dense center and sparse edges. Specifically, the lasers in the edge channels can correspond to a larger field of view angle in space, while the lasers in the center channel are less affected by the distortion of the emitting lens 112. More pixels can be applied to the center field of view, and a higher pixel density can be maintained in the center field of view, achieving relatively high resolution of the center field of view. In this way, when the laser array size in the transmitter 111 is small, the transmitting end 110 can simultaneously achieve coverage of a larger FOV and encryption of its center field of view. For example, the laser array size can be less than 500mm 2 , less than 400mm 2 , less than 300mm 2 , less than 200mm 2 , less than 100mm 2 Alternatively, the concave surface of the first meniscus lens 91 may face the emitter 111 .

[0091] As shown in Figure 10, the receiving lens 122 can distort the photosensitive surface of the evenly distributed detectors into a structure with dense center and sparse edges. Specifically, the detectors in the edge channels can correspond to a larger field of view angle in space, while the detectors in the center channel are less affected by the distortion of the receiving lens 122. More pixels can be applied to the center field of view, and a higher pixel density can be maintained in the center field of view, thereby achieving relatively high resolution of the center field of view. In this way, when the detector array size in the receiver 121 is small, the receiving end 120 can simultaneously achieve coverage of a larger FOV and encryption of its center field of view. For example, the detector array size can be less than 500mm 2 , less than 400mm 2 , less than 300mm 2 , less than 200mm 2 , less than 100mm 2 Alternatively, the concave surface of the second meniscus lens 101 may face the receiver 121 .

[0092] In some embodiments of the present disclosure, the transmitting lens 112 can expand the transmitting field of view of the transmitter 111 so that the field of view angle of the transmitting end 110 is greater than or equal to 150°, and the receiving lens 122 can expand the receiving field of view of the receiver 121 so that the FOV of the receiving end 120 is greater than or equal to 150°, and the focal length of the transmitting lens 112 can be less than or equal to 10 mm, and the focal length of the receiving lens 122 can be less than or equal to 10 mm.

[0093] In some embodiments of the present disclosure, the transmitting end may adopt various types of lasers, including but not limited to vertical-cavity surface-emitting laser (VCSEL), edge-emitting laser (EEL), etc.; the receiving end may adopt various types of detectors, including but not limited to single-photon avalanche diode (SPAD), avalanche photodiode (APD), silicon photomultiplier (SiPM), etc.

[0094] According to another exemplary embodiment of the present disclosure, the present disclosure also proposes an optical transceiver assembly for a laser radar, comprising: a transmitter, including a laser, configured to transmit a light beam; a receiver, including a detector, configured to receive an echo generated by the light beam after being reflected by an object and generate an electrical signal; a spectrometer, configured to guide and separate the light beam and the echo; a transceiver lens, configured to shape the light beam and guide it to an external field of view, and transmit the echo to the receiver; the ratio of the transmission light path image height to the reception light path image height of the transceiver lens at a preset field of view angle is within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold. The transmission light path image height can refer to the distance between the center of the laser emitting a light beam with a certain field of view angle and the main optical axis of the transmission light path. The reception light path image height can refer to the distance between the center of the detector receiving the echo with a certain field of view angle and the main optical axis of the reception light path. Among them, since the spectrometer can guide and separate light beams and echoes, it may cause the transmitting light path or the receiving light path to be bent. Therefore, if the transmitting light path (or receiving light path) is bent by the spectrometer, the aforementioned main optical axis may be the main optical axis of the transmitting light path (or receiving light path) after the bend; if the transmitting light path (or receiving light path) is not bent by the spectrometer, the aforementioned main optical axis may be the main optical axis of the transmitting light path (or receiving light path) that has not been bent.

[0095] FIG11 illustrates a schematic diagram of an exemplary optical transceiver assembly for a lidar system consistent with some embodiments of the present disclosure. Several details of optical transceiver assembly 1100 are identical to those of optical transceiver assembly 100 described above with respect to FIG1-10 and are not further described here. The following primarily describes the differences between optical transceiver assembly 1100 and FIG1-11 .

[0096] The optical transceiver assembly 1100 for a LiDAR radar system may include a transmitter 1110, a receiver 1120, a spectrometer 1130, and a transceiver lens 1140. Transmitter 1110 includes a laser that emits a light beam. Receiver 1120 includes a detector that receives the return light after it is reflected from an object and generates an electrical signal.

[0097] Compared to the optical transceiver assembly 100 having a paraxial optical path, the optical transceiver assembly 1100 has a coaxial optical path, wherein the transmitting optical path and the receiving optical path at least partially overlap. In this embodiment, the optical transceiver assembly 1100 includes a spectrometer 1130 and a transceiver lens 1140 that serves as both a transmitting optical path lens and a receiving optical path lens. The spectrometer 1130 can be configured to guide and separate the light beam and the echo. After the light beam is shaped and guided by the transceiver lens 1140, its detection range in space forms the transmitting field of view of the optical transceiver assembly 1100. The spatial range that the receiver 1120 can detect through the transceiver lens 1140 forms the receiving field of view of the optical transceiver assembly 1100. As shown in Figure 11, the spectrometer 1130 can reflect at least a portion of the light beam emitted by the transmitter 1110 for transmission to the transceiver lens 1140, which can shape the light beam and guide it to an external field of view. The transceiver lens 1140 can also guide the echo of the light beam after it is reflected by the object to the optical splitter 1130. The optical splitter 1130 can transmit at least a portion of the echo and transmit it to the receiver 1120. It should be noted that in some embodiments, the positions of the transmitter 1110 and the receiver 1120 can also be interchanged. In this case, the optical splitter 1130 can transmit at least a portion of the light beam emitted by the transmitter 1110 to transmit it to the transceiver lens 1140, and can reflect at least a portion of the echo and transmit it to the receiver 1120.

[0098] In the optical transceiver assembly 1100, the transmitter 111 and the receiver 121 of the optical transceiver assembly 1100 can use uniformly distributed optoelectronic devices (for example, lasers and detectors). In some embodiments of the present disclosure, the transmitting end and the receiving end can use the same transceiver lens 1140 (as shown in Figure 11), and the focal lengths of the transmitting end and the receiving end are the same, so the size of the transmitter 1110 can match the size of the receiver 1120 to make the overlap of the field of view of the laser and the field of view of the detector greater than the second set threshold, which realizes that the field of view of the laser is aligned with the field of view of the detector. As an example, the second set threshold can be between 50% and 90%, for example, 50%, 60%, 80% or 90%.

[0099] In some embodiments of the present disclosure, the transmitting end and the receiving end of the optical transceiver assembly 1100 may also have different focal lengths. Referring to Figures 12-14 , several examples of the transmitting end and the receiving end of the optical transceiver assembly 1100 having different focal lengths are shown.

[0100] As shown in FIG12 , the transceiver lens may include a first lens 1141 and a second lens 1142. The first lens 1141 may serve as a common lens for both the transmitting and receiving optical paths, while the second lens 1142 may serve as a dedicated lens for the transmitting optical path. In this case, the first lens 1141 and the second lens 1142 form the transmitting optical path lens, while the first lens 1141 forms the receiving optical path lens.

[0101] As shown in FIG13 , the transceiver lens may include a first lens 1141 and a third lens 1143. The first lens 1141 may serve as a common lens for both the transmitting and receiving optical paths, while the third lens 1143 may serve as a dedicated lens for the receiving optical path. In this case, the first lens 1141 forms the transmitting optical path lens, while the first lens 1141 and the third lens 1143 form the receiving optical path lenses.

[0102] As shown in Figure 14, the transceiver lens may include a first lens 1141, a second lens 1142, and a third lens 1143. The first lens 1141 may serve as a common lens for both the transmitting and receiving optical paths, the second lens 1142 may serve as a dedicated lens for the transmitting optical path, and the third lens 1143 may serve as a dedicated lens for the receiving optical path. In this case, the first lens 1141 and the second lens 1142 form the transmitting optical path lens, while the first lens 1141 and the third lens 1143 form the receiving optical path lens.

[0103] In the above embodiment, because the transmitting and receiving optical paths have different lens compositions, there may be distortion mismatches. This can cause the laser beam, emitted by the laser, to reflect off an object, resulting in an echo that fails to reach the detector, i.e., a mismatch occurs between the light-emitting and light-receiving surfaces. To address this issue, the ratio of the transmitting optical path image height to the receiving optical path image height at a preset field of view angle of the transmitting and receiving lenses is within a first threshold range, such that the overlap between the laser's field of view and the detector's field of view exceeds a second predetermined threshold. The transmitting optical path image height can refer to the distance between the center of the laser emitting a beam with a certain field of view angle and the principal optical axis of the transmitting optical path. The receiving optical path image height can refer to the distance between the center of the detector receiving an echo with a certain field of view angle and the principal optical axis of the receiving optical path. In this way, both the transmitter 1110 and the receiver 1120 can include evenly distributed optoelectronic devices, and the laser's field of view and the detector's field of view can substantially overlap. However, for detection, it is sufficient that the laser's field of view and the field of view of at least one detector overlap, and that the overlap exceeds a predetermined threshold. As an example, the second set threshold may be between 50% and 90%, such as 50%, 60%, 80% or 90%.The value of the first threshold interval is related to the focal length of the transmitting light path lens and the receiving light path lens.

[0104] In some embodiments, the ratio of the emission light path image height to the reception light path image height of the transceiver lens at a preset field of view angle is within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold.

[0105] In some embodiments, the ratio of the emission light path image height to the reception light path image height of the transceiver lens at multiple preset field of view angles is within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold.

[0106] In some embodiments, the ratio of the emission light path image height to the reception light path image height of the transceiver lens at each preset field of view angle is within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold.

[0107] In embodiments of the present disclosure, the transceiver lens 1140 can expand the transmitting field of view of the transmitter 1110 and the receiving field of view of the receiver 1120, so that the field of view of the optical transceiver assembly 1100 is greater than or equal to 140°. The focal length of the transceiver lens 1140 can be less than or equal to 16 mm. Compared to solutions that use moving parts to rotate the optical transceiver assembly or use scanning devices to change the propagation direction of the light beam to achieve a larger FOV, the present disclosure contemplates using a lens that expands the field of view to replace moving parts or scanning devices to achieve a lidar with an ultra-large field of view. This can expand the lidar's FOV while reducing the size requirements of the optoelectronic components in the lidar and eliminating the additional cost associated with moving parts or scanning devices. In some embodiments of the present disclosure, the transceiver lens 1140 can include a meniscus lens. The concave surface of the meniscus lens can face the direction of incidence of the light beam, while the convex surface faces the direction of incidence of the echo. The meniscus lens can expand the transmitting field of view of the transmitter 1110 and the receiving field of view of the receiver 1120, as described above with reference to Figures 9 and 10. Optionally, the meniscus lens may have a negative optical power, thereby shortening the overall focal length of the transceiver lens 1140 .

[0108] In some embodiments of the present disclosure, the transceiver lens 1140 can expand the transmitting field of view of the transmitter 1110 and the receiving field of view of the receiver 1120 so that the field of view angle of the optical transceiver assembly is greater than or equal to 150°, and the focal length of the transceiver lens 1140 can be less than or equal to 10 mm.

[0109] In some embodiments, the optical splitter 1130 may include a partially reflective mirror (e.g., a semi-transparent, semi-reflective mirror), which transmits at least a portion of the light beam and reflects at least a portion of the echo, or reflects at least a portion of the light beam and transmits at least a portion of the echo. In some embodiments, the optical splitter 1130 may include a reflector having a small hole, which allows at least a portion of the light beam to be transmitted through the small hole in the reflector to the transceiver lens, and at least a portion of the echo may be reflected by the reflector to the receiver 1120. In some embodiments, the optical splitter 1130 may include a small reflector, which allows at least a portion of the light beam to be reflected by the small reflector to the transceiver lens 1140, and at least a portion of the echo may be transmitted from the periphery of the small reflector to the receiver.

[0110] In an optional embodiment of the present disclosure, the optical transceiver assembly 1100 can employ polarization splitting to reduce energy loss. Specifically, referring to FIG15 , the optical splitter can include a polarization beam splitter 1131 for reflecting P light and transmitting S light, and the optical splitter can also include a quarter-wave plate 1132 located between the polarization beam splitter 1131 and the transceiver lens 1140. In this optional embodiment, the polarization state of the light beam emitted by the transmitter 1110 can be P polarization, that is, the transmitter 1110 emits P light. The P light can be reflected by the optical splitter 1130 and guided to the external field of view through the quarter-wave plate 115 and the transceiver lens 1140. The echo returns to the optical splitter 1130 through the transceiver lens 1140 and the quarter-wave plate 1150. Since the P light is converted into S light after passing through the quarter-wave plate 1150 twice, the echo as S light is transmitted by the optical splitter 1130 and transmitted to the receiver 1120. It should be noted that, in some embodiments, the polarization beam splitter 1131 may also transmit P light and reflect S light; in this case, the positions of the transmitter 1110 and the receiver 1120 in FIG. 12 may be interchanged, or the transmitter 1110 may emit S light.

[0111] The optical transceiver assembly disclosed herein allows for a uniformly distributed transmitter / receiver design when using a transceiver lens with distortion.

[0112] Optionally, the present disclosure can use an F-theta lens with an expanded FOV as the transmitting and receiving lens. Due to its inherent distortion, the distortion curves of the transmitting and receiving lenses can be reasonably designed to ensure that the degree of distortion at the edge of the field of view (corresponding to a larger field of view angle) is greater than the degree of distortion at the center of the field of view (corresponding to a smaller field of view angle). This allows the image height to converge quickly at the edge of the lens, while meeting the requirements for the central field of view angular resolution and FOV size while avoiding excessive device size, thus achieving a balance between the angular resolution and device size of the central field of view.

[0113] Secondly, the laser radar using the optical transceiver component disclosed in the present invention can generate a point cloud that is dense in the center of the field of view and sparse at the edge of the field of view. This is because the detectors are generally uniform in size and evenly arranged. The lens design disclosed in the present invention allows for greater distortion at the edge of the field of view (to reduce the size of the device). Therefore, the closer the detector is to the edge of the field of view, the larger the corresponding field of view angle interval, that is, the sparser the corresponding point cloud. Laser radars are usually more concerned with the detection situation in the center of the field of view, so the optical transceiver component disclosed in the present invention takes advantage of this point, allowing the laser radar to obtain a large FOV and a point cloud that is dense in the center of the field of view and sparse at the edge of the field of view.

[0114] Larger FOV coverage and finer angular resolution are both design goals of LiDAR. When the number of LiDAR detection channels is fixed, it is generally difficult to take both into account. Due to its working environment, the detection targets of vehicle-mounted LiDAR are mainly distributed in the central field of view, and the long-distance measurement capability requirements for the central field of view are higher than those for the edge field of view. Since objects appear larger when they are closer and smaller when they are farther away, the volume of distant objects in the LiDAR field of view is relatively small. In order to detect distant objects in the central field of view, the resolution of the central field of view needs to be increased. Therefore, how to increase the resolution of the central field of view of the LiDAR while maintaining a larger FOV coverage is also a technical problem that needs to be solved urgently in this field.

[0115] The present disclosure also proposes an optical transceiver assembly for a laser radar. The optical transceiver assembly includes a transmitting end and a receiving end. The transmitting end includes a transmitter and a transmitting lens. The transmitter includes a laser array configured to transmit a light beam. The receiver includes a receiving lens and a receiver. The receiver includes a detector array configured to receive an echo. The angular resolution of a first area of ​​the field of view of the optical transceiver assembly is different from the angular resolution of a second area of ​​the field of view of the optical transceiver assembly. At least one of the transmitting lens and the receiving lens includes a negative meniscus lens. The optical transceiver assembly for a laser radar disclosed in the present disclosure uses a negative meniscus lens as a component in the lens, and uses the distortion of the lens group itself to achieve central field of view encryption and expand FOV coverage.

[0116] As described above in conjunction with FIG1 , the optical transceiver assembly 100 for a lidar may include a transmitter 110 and a receiver 120. Transmitter 110 may include a transmitter 111. Transmitter 111 may include a laser array capable of emitting a light beam. Transmitter 110 may also include a transmitting lens 112, which may direct the light beam into the lidar's field of view. Receiving end 120 may include a receiver 121 and a receiving lens 122. Receiving lens 122 may direct the echo formed by the light beam reflecting off an object to receiver 121. Receiver 121 may include a detector array for receiving the echo.

[0117] In some embodiments, the angular resolution of a first region of the field of view of the optical transceiver assembly 100 may be different from the angular resolution of a second region of the field of view of the optical transceiver assembly 100. In some embodiments, the second region is closer to the edge of the field of view of the optical transceiver assembly than the first region. In other embodiments, the first region is closer to the edge of the field of view of the optical transceiver assembly than the second region. In some embodiments, the first region may be the center region of the field of view of the optical transceiver assembly 100, and the second region may be the edge region of the field of view of the optical transceiver assembly 100. The angular resolution of the center region of the field of view of the optical transceiver assembly 100 may be different from the angular resolution of the edge region of the field of view of the optical transceiver assembly 100. The field of view of the optical transceiver assembly 100 can be divided into a center region and an edge region. The center region may refer to an area close to the optical axis, such as an area within a specific threshold range from the optical axis. The edge region may refer to an area far from the optical axis, such as an area outside a specific threshold range from the optical axis. The angular resolution of the optical transceiver assembly 100 can be characterized by the angle between light beams of adjacent channels.

[0118] See Figure 16, which shows an example of an optical transceiver assembly 100 having a non-uniform angular resolution. In some examples, the transmitter 111 may include a laser array consisting of 40 lasers, and the optical transceiver assembly 100 may emit 40 laser beams in each detection cycle, distributed at different angles in the vertical direction (e.g., the y direction), so that multiple laser beams can detect multiple points in one scanning cycle. In other examples, the optical transceiver assembly may emit more or fewer laser beams in each detection cycle. As shown in the example of Figure 16, the angular resolution of the central area of ​​the field of view of the optical transceiver assembly 100 is greater than the angular resolution of the edge area of ​​the field of view of the optical transceiver assembly 100, that is, the laser beams are arranged more densely near the vertical angle of 0°, and the laser beams are arranged more sparsely in the area away from 0°. In this way, the angular resolution of the central area of ​​the lidar can be higher, and more precise target recognition and measurement can be provided for the central area. LiDAR is usually more interested in targets in the center area because the center area is usually located in the vehicle's driving path and contains other vehicles, pedestrians, roadblocks, and other targets of interest. Therefore, it is expected that the center area has higher detection resolution and longer detection range. For edge areas, such as areas with large vertical angles (such as the sky) and areas with small vertical angles (such as the ground), LiDAR detection priority is relatively low.

[0119] In some embodiments, the angular resolution of some areas of the optical transceiver assembly 100 may be uniform, while the angular resolution of other areas may be non-uniform. In the example of Figure 16, laser beams 6 to 30 may be set so that the vertical angular resolution of two adjacent beams is a first preset value, laser beams 5 to 6 and laser beams 30 to 38 may be set so that the vertical angular resolution of two adjacent beams is a second preset value, and other laser beams may be arranged to be non-uniformly distributed. In other embodiments, the angular resolution of the central area of ​​the optical transceiver assembly 100 may be uniform and the angular resolution of the edge area may also be uniform, but the angular resolution of the central area is greater than the angular resolution of the edge area.

[0120] In the above manner, a non-uniform distribution of angular resolutions in multiple areas of the field of view of the optical transceiver assembly 100 can be achieved. In some embodiments, each of the multiple areas may include one or more channels / light beams. It should be noted that Figure 16 only shows an example in which the angular resolution of the central area of ​​the field of view of the optical transceiver assembly 100 is different from the angular resolution of the edge area of ​​the field of view of the optical transceiver assembly 100. The differentiated manner of angular resolution of the central area of ​​the field of view and the edge area of ​​the field of view proposed in the present disclosure is not limited to this. Those skilled in the art can conceive of a variety of non-uniform distribution methods of angular resolution based on the teachings of the present disclosure.

[0121] Providing a negative meniscus lens in the lens can help achieve a non-uniform distribution of angular resolution. At least one of the transmitting lens 112 and the receiving lens 122 may include a negative meniscus lens.

[0122] In some embodiments of the present disclosure, the transmitting lens 112 may include at least one negative meniscus lens 31 to expand the field of view (FOV) of the transmitter 111, as shown in Figure 17. Those skilled in the art will appreciate that the transmitting lens 112 may also include a primary light group 32, which can shape (e.g., collimate) the laser beam emitted by the transmitter 111. In this way, the transmitting lens 112 may have pincushion distortion, which can be used to distort the uniformly distributed laser light-emitting surface into a structure with dense center and sparse edges, as shown in Figure 17. In some embodiments, the lasers in the edge channels can correspond to a larger field of view angle in space, while the lasers in the center channel are less affected by the distortion of the transmitting lens 112. More pixels can be applied to the center field of view, and a higher pixel density can be maintained in the center field of view, thereby improving the angular resolution of the center area of ​​the field of view. When the laser array in the transmitter 111 includes multiple lasers evenly distributed, the transmitting end 110 can simultaneously achieve coverage of a larger field of view and density of the center field of view. As shown in FIG. 2 , the laser array in the transmitter 111 may be arranged into a one-dimensional array or a two-dimensional array, with multiple lasers evenly distributed in the row / column directions.

[0123] Optionally, the concave surface of the negative meniscus lens 31 may face the incident direction of the light beam.

[0124] In some embodiments of the present disclosure, the receiving lens 122 may include at least one negative meniscus lens 41 to expand the field of view of the receiver 121, as shown in FIG18 . Those skilled in the art will appreciate that the receiving lens 122 may also include a receiving primary light group 42, which can guide the echo to the receiver 121. In this manner, the receiving lens 122 may exhibit pincushion distortion, which can be utilized to distort the photosensitive surfaces of uniformly distributed detectors into a structure with denser centers and sparser edges, as shown in FIG18 . In some embodiments, detectors in edge channels can correspond to a larger field of view in space, while detectors in center channels are less affected by the distortion of the receiving lens 122. More pixels can be applied to the center field of view, maintaining a higher pixel density in the center field of view, and achieving relatively high resolution in the center field of view. When the detector array in the receiver 121 includes multiple uniformly distributed detectors, the receiving end 120 can simultaneously achieve coverage of a larger FOV and density in the center field of view. As shown in FIG3 , the detector array in the receiver 121 may be arranged into a one-dimensional array or a two-dimensional array, with multiple detectors evenly distributed in the row / column directions.

[0125] Optionally, the convex surface of the negative meniscus lens 41 may face the incident direction of the echo.

[0126] In some embodiments of the present disclosure, referring to FIG19 , the transmitter 111 and the receiver 121 may be disposed on the same circuit board 70, thereby fixing the relative positions of the transmitter 111 and the receiver 121. This arrangement helps reduce the design complexity and assembly difficulty of the transmitting lens 112 and the receiving lens 122, as there is no need to consider the positional changes between the transmitter 111 and the receiver 121 during the design.

[0127] In some embodiments of the present disclosure, the transceiver ends (transmitter 110 and receiver 120) of the optical transceiver assembly 100 may both adopt a lens design including a negative meniscus lens, or may adopt a lens design including a negative meniscus lens at only one end (transmitter / receiver), while a lens without a negative meniscus lens and a non-uniformly distributed optoelectronic device design may be adopted at the other end (receiver / transmitter).

[0128] As an example, when the transmitting end 110 includes a transmitting lens design with a negative meniscus lens and a uniformly distributed laser array, the receiving end 120 may include a receiving lens design without a negative meniscus lens and a non-uniformly distributed detector array. Referring to Figures 20A and 20C, the non-uniformly distributed detector array may include a plurality of detectors 80 that are non-uniformly distributed along a first direction (e.g., the y direction). Referring to Figures 20B and 20C, in some embodiments, the plurality of detectors 80 may also be non-uniformly distributed along a second direction (e.g., the x direction). The second direction is different from the first direction, for example, it may be perpendicular to the first direction. The angular resolution of the third region of the detector array may be different from the angular resolution of the fourth region of the detector array. In some embodiments, the fourth region is closer to the edge of the detector array than the third region. In other embodiments, the third region is closer to the edge of the detector array than the fourth region. In some embodiments, the third region may be the central region of the detector array, and the fourth region may be the edge region of the detector array. In the examples shown in Figures 20A-20C, the detector density in the central region of the detector array is greater than the detector density in the edge region of the detector array.

[0129] As another example, when the receiving end 120 includes a receiving lens design with a negative meniscus lens and a uniformly distributed detector array, the transmitting end 110 may include a transmitting lens design without a negative meniscus lens and a non-uniformly distributed laser array. Referring to Figures 21A and 21B, the non-uniformly distributed laser array may include a plurality of lasers 90 that are non-uniformly distributed along a first direction (e.g., y direction) or a second direction (e.g., x direction). Referring to Figure 21C, in some embodiments, when the laser array is a two-dimensional array, the plurality of lasers may be non-uniformly distributed along both the first direction and the second direction (e.g., x direction and y direction). The second direction is different from the first direction, for example, it may be perpendicular to the first direction. The angular resolution of the fifth region of the laser array may be different from the angular resolution of the sixth region of the laser array. In some embodiments, the sixth region is closer to the edge of the laser array than the fifth region. In other embodiments, the fifth region is closer to the edge of the laser array than the sixth region. In some embodiments, the fifth region may be the central region of the laser array, and the sixth region may be the edge region of the laser array. In the example shown in FIG. 21A-21C , the laser density in the central region of the laser array is greater than the laser density in the edge regions of the laser array.

[0130] In some embodiments of the present disclosure, the arrangement of components and lens design in the transmitter 110 and receiver 120 can be coordinated to ensure that the light spot emitted by a laser in the laser array at least partially overlaps with the field of view of at least one detector in the detector array. This ensures a consistent relationship between the fields of view of the laser radar's lasers and the detectors, improving detection accuracy.

[0131] In some embodiments of the present disclosure, the transmitting lens or the receiving lens includes any one of the following: a wide-angle lens and a fisheye lens. This can expand the horizontal and / or vertical field of view of the laser radar, for example, to greater than 140°, greater than 150°, greater than 160°, greater than 170°, greater than 180°, or even greater.

[0132] In some embodiments of the present disclosure, the optical transceiver assembly 100 may further include a light homogenizer disposed in the optical path of the transmitting end 110. The light homogenizer may be used in conjunction with a one-dimensional array of lasers or an elongated two-dimensional laser array to achieve the emission effect of the laser array shown in FIG2 . The elongated two-dimensional laser array may include M rows (in the x-direction) and N columns (in the y-direction) of lasers, where M is much greater than N, or M is much less than N.

[0133] Optionally, the homogenizer can be located on the light-emitting side of the transmitting lens 112, so that the transmitter 111, the transmitting lens 112 and the homogenizer can be freely adjusted with each other to obtain the desired light field distribution. Optionally, the homogenizer can be located near the aperture inside the transmitting lens 112, for example, the homogenizer is integrated with the transmitting lens 112, so that the entirety can be adjusted relative to the transmitter 111 to obtain the desired light field distribution. Optionally, the homogenizer can be located on the light-emitting side of the transmitter 111, for example, the homogenizer is integrated with the transmitting lens 111, so that the entirety can be adjusted relative to the transmitting lens 112 to obtain the desired light field distribution. Optionally, the homogenizer can be located between the transmitter 111 and the transmitting lens 112 and the three are independent of each other, so that the transmitter 111, the transmitting lens 112 and the homogenizer can be freely adjusted with each other to obtain the desired light field distribution. For example, free adjustment can include changing the spacing between these components or adjusting the angles of these components relative to each other.

[0134] As an example, the light homogenizer may include, but is not limited to, a diffuser, a microlens array, a diffractive optical element (DOE), an optical waveguide, and the like.

[0135] In some embodiments of the present disclosure, the transmitting end may adopt various types of lasers, including but not limited to vertical-cavity surface-emitting lasers (VCSEL), edge-emitting lasers (EEL), etc.; the receiving end may adopt various types of detectors, including but not limited to single photon avalanche diode (SPAD), avalanche photodiode (APD), silicon photomultiplier (SiPM), etc.

[0136] The angular resolution of the first area of ​​the field of view of the optical transceiver assembly of the present disclosure is different from the angular resolution of the second area of ​​the field of view of the optical transceiver assembly. At the same time, a design is adopted in which at least one of the transmitting lens and the receiving lens includes a negative meniscus lens. In this way, the central field of view of the laser radar can be encrypted and the FOV coverage can be expanded by utilizing the distortion of the lens itself. In addition, with the improvement of the integration of optoelectronic devices, such as the chipization of the transceiver, the transmitting end / receiving end devices have become integrated devices. For IC design, uniformly distributed lasers / detectors and processing circuits are an economical and low-complexity solution. Therefore, the present disclosure proposes a method of utilizing the distortion of the lens itself to achieve central channel encryption.

[0137] According to another exemplary embodiment of the present disclosure, a laser radar is also provided.

[0138] As shown in FIG. 22 , the laser radar 2200 may include the optical transceiver assembly 100 / 1100 and the controller 200 described above.

[0139] The transmitting end 110 in the optical transceiver component 100 / 1100 can provide a light beam 1001 into space to illuminate an object 20 in the space. At least part of the light beam 1001 is reflected by the object 20 to form an echo 1002, and at least part of the optical signal (such as photons) of the echo 1002 is collected by the receiving end 120.

[0140] The controller 200 is connected to the optical transceiver assembly 100 and can control the transmitting end 110 to transmit a light beam and determine at least one of the distance and reflectivity of the object 20 based on at least the echo received by the receiving end 120 .

[0141] In some embodiments of the present disclosure, the controller 200 may also control multiple lasers of the transmitter to emit light simultaneously or in a time-sharing manner.

[0142] As an example, the controller 200 may include but is not limited to: a central processing unit (CPU), a field programmable gate array (FPGA), a digital signal processing (DSP) and other chips.

[0143] According to another exemplary embodiment of the present disclosure, a terminal device is further provided. The terminal device may include the laser radar 2200 described above. The terminal device may be a vehicle (e.g., a smart car), a surveying and mapping device, an aircraft (e.g., a drone), a ship, etc.

[0144] It should be understood that the above description is illustrative and not restrictive. For example, the above embodiments (and / or aspects thereof) can be used in combination with each other. In addition, without departing from the scope of the present disclosure, many modifications can be made to adapt specific conditions or materials to the teachings of the various embodiments of the present disclosure. Although the sizes and types of materials described herein are used to define the parameters of the various embodiments of the present disclosure, the various embodiments are not meant to be restrictive, but rather exemplary embodiments. Upon reading the above description, many other embodiments will be apparent to those skilled in the art. Therefore, the scope of the various embodiments of the present disclosure should be determined with reference to the appended claims, and the full range of equivalents to which these claims are entitled.

Claims

1. An optical transceiver assembly for a laser radar, comprising: The transmitter includes: a transmitter, including a laser, the transmitter configured to transmit a light beam; and a transmitting lens configured to shape the light beam and direct the light beam to an external field of view; The receiving end includes: A receiving lens, configured to transmit an echo generated after the light beam is reflected by an object to a receiver; a receiver, including a detector, the receiver being configured to receive the echo and generate an electrical signal, The ratio of the image heights of the transmitting lens and the receiving lens at a preset field of view angle is within a first threshold interval, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold.

2. The optical transceiver assembly according to claim 1, characterized in that: The second set threshold is 50%, 60%, 80% or 90%.

3. The optical transceiver assembly according to claim 1, characterized in that: The field of view angle of the transmitting end is greater than or equal to 140°, the field of view angle of the receiving end is greater than or equal to 140°, the focal length of the transmitting lens is less than or equal to 16 mm, and the focal length of the receiving lens is less than or equal to 16 mm.

4. The optical transceiver assembly according to claim 3, characterized in that: The emitting lens at least includes a first meniscus lens located on the light emitting side, the concave surface of the first meniscus lens faces the emitter, and the first meniscus lens has a negative optical power.

5. The optical transceiver assembly according to claim 3, characterized in that: The receiving lens at least includes a second meniscus lens located on the light incident side, the concave surface of the second meniscus lens faces the receiver, and the second meniscus lens has a negative optical power.

6. The optical transceiver assembly according to claim 3, characterized in that: At least one of the horizontal field of view angle and the vertical field of view angle of the transmitting end is less than 180°, and at least one of the horizontal field of view angle and the vertical field of view angle of the receiving end is less than 180°.

7. The optical transceiver assembly according to claim 6, characterized in that: The horizontal field of view angle of the transmitting end is greater than 180°, the horizontal field of view angle of the receiving end is greater than 180°, and the transmitting lens and the receiving lens are arranged vertically.

8. The optical transceiver assembly according to claim 6, characterized in that: The vertical field of view angle of the transmitting end is greater than 180°, the vertical field of view angle of the receiving end is greater than 180°, and the transmitting lens and the receiving lens are arranged horizontally.

9. The optical transceiver assembly according to claim 3, characterized in that: The degree of distortion of the transmitting lens and the receiving lens at the edge of the field of view is greater than the degree of distortion at the center of the field of view.

10. The optical transceiver assembly according to claim 3, characterized in that: The field of view angle of the transmitting end is greater than or equal to 150°, the field of view angle of the receiving end is greater than or equal to 150°, and the focal length of the transmitting lens is less than or equal to 10 mm, and the focal length of the receiving lens is less than or equal to 10 mm.

11. The optical transceiver assembly according to claim 1, characterized in that: The focal length of the transmitting lens is smaller than the focal length of the receiving lens.

12. The optical transceiver assembly according to claim 11, characterized in that: The size of the transmitter is smaller than the size of the receiver.

13. An optical transceiver assembly for a laser radar, comprising: a transmitter, including a laser, the transmitter configured to emit a light beam; A receiver, comprising a detector, wherein the receiver is configured to receive an echo generated after the light beam is reflected by an object and generate an electrical signal; A beam splitter configured to guide and separate the light beam and the echo; a transceiver lens configured to shape the light beam and direct the light beam to an external field of view, and transmit the echo to the receiver; The ratio of the image height of the transmitting optical path to the image height of the receiving optical path of the transceiver lens at a preset field of view angle is within a first threshold range, so that the overlap between the field of view of the laser and the field of view of the detector is greater than a second set threshold.

14. The optical transceiver assembly according to claim 13, characterized in that: The field of view angle of the optical transceiver assembly is greater than or equal to 140°, and the focal length of the transceiver lens is less than or equal to 16 mm.

15. The optical transceiver assembly according to claim 14, characterized in that: The transceiver lens at least comprises a meniscus lens, the concave surface of the meniscus lens faces the incident direction of the light beam, and the convex surface of the meniscus lens faces the incident direction of the echo.

16. The optical transceiver assembly according to claim 14, characterized in that: The field of view angle of the optical transceiver assembly is greater than or equal to 150°, and the focal length of the transceiver lens is less than or equal to 10 mm.

17. An optical transceiver assembly for a laser radar, comprising: The transmitter has: a transmitter including a laser array configured to emit a light beam; and Launch the lens; A receiver having: Receive lens; a receiver including a detector array configured to receive the echoes, The angular resolution of a first area of ​​the field of view of the optical transceiver assembly is different from the angular resolution of a second area of ​​the field of view of the optical transceiver assembly, and at least one of the transmitting lens and the receiving lens includes a negative meniscus lens.

18. The optical transceiver assembly according to claim 17, characterized in that: The second area is closer to the edge of the field of view of the optical transceiver assembly than the first area.

19. The optical transceiver assembly according to claim 17, characterized in that: The transmitter and the receiver are arranged on the same circuit board.

20. The optical transceiver assembly according to claim 17, characterized in that: The emitting lens includes a first negative meniscus lens, and the laser array includes a plurality of lasers that are evenly distributed.

21. The optical transceiver assembly according to claim 20, characterized in that: The concave surface of the first negative meniscus lens faces the incident direction of the light beam.

22. The optical transceiver assembly according to claim 17, characterized in that: The detector array includes a plurality of detectors distributed non-uniformly along a first direction.

23. The optical transceiver assembly according to claim 22, characterized in that: The plurality of detectors are non-uniformly distributed along a second direction, which is different from the first direction.

24. The optical transceiver assembly according to claim 22, characterized in that: The detector density of the third region of the detector array is greater than the detector density of the fourth region of the detector array.

25. The optical transceiver assembly according to claim 24, characterized in that: The fourth region is closer to an edge of the detector array than the third region.

26. The optical transceiver assembly according to claim 17, characterized in that: The receiving lens includes a second negative meniscus lens, and the detector array includes a plurality of detectors that are evenly distributed.

27. The optical transceiver assembly according to claim 26, characterized in that: The convex surface of the second negative meniscus lens faces the incident direction of the echo.

28. The optical transceiver assembly according to claim 17, characterized in that: The laser array includes a plurality of lasers distributed non-uniformly along a first direction.

29. The optical transceiver assembly according to claim 28, characterized in that: The plurality of lasers are non-uniformly distributed along a second direction, which is different from the first direction.

30. The optical transceiver assembly according to claim 28, characterized in that: The laser density of the fifth region of the laser array is greater than the laser density of the sixth region of the laser array.

31. The optical transceiver assembly according to claim 30, characterized in that: The sixth region is closer to the edge of the laser array than the fifth region.

32. The optical transceiver assembly according to claim 17, characterized in that: A light spot emitted by a laser in the laser array at least partially overlaps with a field of view of at least one detector in the detector array.

33. The optical transceiver assembly according to claim 17, characterized in that: The transmitting lens or the receiving lens includes at least one of the following: a wide-angle lens or a fisheye lens.

34. The optical transceiver assembly according to claim 17, characterized in that: The optical transceiver assembly also includes a light homogenizer arranged on the optical path of the transmitting end.

35. A laser radar, comprising: The optical transceiver assembly according to any one of claims 1 to 34; as well as The controller is configured as: Controlling the emitter to emit the light beam; and At least one of a distance and a reflectivity of an object is determined based on at least the echo received by the receiver.

36. The laser radar according to claim 35, characterized in that The controller is also configured to control the multiple lasers of the transmitter to emit light simultaneously or in a time-sharing manner.

37. A terminal device, comprising a laser radar as described in claim 35 or 36.

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