Optical transceiver assembly for laser radar, laser radar and terminal equipment

Abstract

The invention relates to an optical transceiver assembly for a laser radar, the laser radar and terminal equipment. The optical transceiver assembly comprises: a transmitting module comprising a transmitter comprising a plurality of lasers, the transmitter being configured to transmit a first light beam; and an emission lens configured to shape the first light beam and guide the first light beam to an external field of view; the receiving module comprises a receiving lens which is configured to transmit echoes generated after the first light beam is reflected by an object to a receiver; the receiver comprises a plurality of detectors, the receiver is configured to receive echoes and generate electric signals, and the ratio of the image height of the transmitting lens to the image height of the receiving lens at each view field angle conforms to a first threshold interval, so that the overlapping degree of the view field of each laser and the view field of at least one detector corresponding to the laser is larger than a second set threshold value.

Description

Technical Field

[0001] The present disclosure relates to the field of lidar, and more particularly to an optical transceiver component for lidar, a lidar including the same, and a terminal device. Background Art

[0002] Lidar is a radar system that detects the position, speed and other characteristic quantities of an object by emitting laser beams, and is an advanced detection method that combines laser technology with optoelectronic detection technology. Due to its advantages such as high resolution, good concealment, strong anti-active interference ability, good low-altitude detection performance, small size and light weight, lidar is widely used in fields such as autonomous driving, traffic communication, unmanned aerial vehicles, intelligent robots, and resource exploration.

[0003] In current lidar technology solutions, it is common to use rotation (motor), scanning (galvanometer, rotating mirror), multi-lens splicing and other methods to achieve the coverage of a larger FOV. Methods such as rotating and scanning devices and multi-lens splicing will increase the complexity and cost of the solution. Lenses with an enlarged field of view can be used to increase the FOV of lidar, but such lenses will inevitably have distortion, resulting in transceiver mismatch of lidar (the echo formed by the light reflected by an object from some transmitters cannot return to the corresponding receiver). For lidar using highly integrated transmitter chips and highly integrated receiver chips, their uniformly distributed transmitters and receivers are more likely to cause transceiver mismatch due to lens distortion. Summary of the Invention

[0004] The purpose of the present disclosure is to overcome the above and / or other problems in the prior art, and provides an optical transceiver component for lidar, which ensures the correspondence between the transceiver of lidar by configuring the image height ratio of the transmitting lens and the receiving lens at each field angle to conform to the first threshold interval. This optical transceiver component allows the use of a uniformly distributed transmitter / receiver design in the case of using transceiver lenses with distortion.

[0005] According to a first aspect of the present disclosure, there is provided an optical transceiver component for lidar, including: a transmitting module, including: a transmitter, including a plurality of lasers, the transmitter being configured to emit a first light beam; and a transmitting lens, being configured to shape the first light beam and guide the first light beam to an external field of view; a receiving module, including: a receiving lens, being configured to transmit the echo generated after the first light beam is reflected by an object to a receiver; a receiver, including a plurality of detectors, the receiver being configured to receive the echo and generate an electrical signal, the ratio of the image height of the transmitting lens to the image height of the receiving lens at each field angle conforms to the first threshold interval, so that the overlap degree of the field of view of each laser and at least one detector corresponding thereto is greater than a second set threshold.

[0006] Optionally, the second set threshold is 50%, 60%, 80% or 90%.

[0007] Optionally, the field of view (FOV) of both the transmitting module and the receiving module is greater than or equal to 140°, and the focal lengths of both the transmitting lens and the receiving lens are less than or equal to 16 mm.

[0008] Optionally, the transmitting lens at least includes a first meniscus lens located on the light-emitting side, the concave surface of the first meniscus lens faces the transmitter, and the first meniscus lens has a negative optical power.

[0009] Optionally, 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.

[0010] Optionally, the horizontal field of view and / or the vertical field of view of the transmitting module is less than 180°, and the horizontal field of view and / or the vertical field of view of the receiving module is less than 180°.

[0011] Optionally, the horizontal field of view of the transmitting module and the receiving module is greater than 180°, and the transmitting lens and the receiving lens are arranged vertically.

[0012] Optionally, the vertical field of view of the transmitting module and the receiving module is greater than 180°, and the transmitting lens and the receiving lens are arranged horizontally.

[0013] Optionally, the distortion degree of the transmitting lens and the receiving lens at the edge of the field of view is greater than that at the center of the field of view.

[0014] Optionally, the field of view (FOV) of both the transmitting module and the receiving module is greater than or equal to 150°, and the focal lengths of both the transmitting lens and the receiving lens are less than or equal to 10 mm.

[0015] Optionally, the focal length of the transmitting lens is less than that of the receiving lens.

[0016] Optionally, the size of the transmitter is less than that of the receiver.

[0017] According to a second aspect of the present disclosure, there is provided an optical transceiver assembly for a laser radar, comprising: a transmitter, comprising a plurality of lasers, the transmitter being configured to transmit a first light beam; a receiver, comprising a plurality of detectors, the receiver being configured to receive an echo of the first light beam after being reflected by an object and to generate an electrical signal; a spectrometer, being configured to guide and separate the first light beam and the echo; a transceiver lens, being configured to shape the first light beam and guide the first light beam to an external field of view, and to transmit the echo to the receiver; a ratio of an image height of the transmitting light path to an image height of the receiving light path of the transceiver lens at each field of view angle conforming to a first threshold interval, so that the degree of overlap between the field of view of each of the lasers and the field of view of at least one of the corresponding detectors is greater than a second set threshold.

[0018] Optionally, the field of view (FOV) 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.

[0019] Optionally, the transceiver lens includes at least a meniscus lens, a concave surface of the meniscus lens faces the incident direction of the first light beam, and a convex surface of the meniscus lens faces the incident direction of the echo.

[0020] Optionally, the field of view (FOV) 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.

[0021] According to a third 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 first light beam; and receive and process the electrical signal generated by the receiver to calculate at least one of the distance and reflectivity of the object.

[0022] Optionally, the controller is further configured to control the multiple lasers of the transmitter to emit light simultaneously or in time-sharing.

[0023] According to a fourth aspect of the present disclosure, a terminal device is provided, comprising the laser radar as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present disclosure may be better understood by describing exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, in which:

[0025] Figure 1 A schematic block diagram of an optical transceiver assembly for a laser radar according to an exemplary embodiment of the present disclosure is shown;

[0026] Figure 2 Several examples of uniformly distributed area array lasers are shown;

[0027] Figure 3 An example of a uniformly distributed detector array is shown;

[0028] Figures 4 - 6 Several examples of the corresponding relationships between the transmitter and the receiver are respectively shown;

[0029] Figure 7 A schematic diagram showing the vertical arrangement of the transmitting lens and the receiving lens is shown;

[0030] Figure 8 A schematic diagram showing the horizontal arrangement of the transmitting lens and the receiving lens is shown;

[0031] Figure 9 A schematic diagram showing the transmitting end including a meniscus lens and its function is shown;

[0032] Figure 10 A schematic diagram showing the receiving end including a meniscus lens and its function is shown;

[0033] Figure 11 A schematic diagram of an optical transceiver module for a lidar according to another exemplary embodiment of the present disclosure is shown;

[0034] Figures 12 to 14 Several embodiments in which the transmitting end and the receiving end of the optical transceiver module have different focal lengths are respectively shown;

[0035] Figure 15 A schematic diagram of an optical transceiver module for a lidar according to an alternative embodiment of the present disclosure is shown; and

[0036] Figure 16 A schematic block diagram of a lidar according to an exemplary embodiment of the present disclosure is shown. Detailed Description of the Invention

[0037] The following will describe the specific embodiments of the present disclosure. It should be noted that in the specific description of these embodiments, for the sake of concise description, this specification may not describe all features of the actual embodiments in detail. It should be understood that in the actual implementation process of any one of the embodiments, just as in the process of any engineering project or design project, in order to achieve the specific goals of the developer and to meet the system-related or business-related restrictions, various specific decisions are often made, and these will also change from one embodiment to another. In addition, it should also be understood that although the efforts made in this development process may be complex and lengthy, for those of ordinary skill in the art related to the content disclosed in the present disclosure, some design, manufacturing, or production changes based on the technical content disclosed in the present disclosure are only conventional technical means and should not be understood as insufficient content of the present disclosure.

[0038] Unless otherwise defined, technical terms or scientific terms used in the claims and the specification shall have the ordinary meanings as understood by those of ordinary skill in the technical field to which this disclosure pertains. The terms "first", "second" and similar terms used in the specification and claims of this patent application of the disclosure do not denote any order, quantity or importance, but are merely used to distinguish different components. The terms such as "a" or "an" do not denote a limitation of quantity, but rather denote the existence of at least one. The terms such as "comprising" or "including" mean that the elements or items appearing before "comprising" or "including" cover the elements or items listed after "comprising" or "including" and their equivalent elements, and do not exclude other elements or items. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0039] In this disclosure, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form new technical solutions. In this disclosure, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form new technical solutions.

[0040] In the description of the embodiments of this disclosure, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: the sole existence of A, the simultaneous existence of A and B, and the sole existence of B. Additionally, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0041] The optical transceiver assembly for a lidar provided according to an embodiment of this disclosure will be described in detail below with reference to the accompanying drawings.

[0042] Light Detection and Ranging (LiDAR) is a radar system that detects features such as the position and speed of an object by emitting laser beams. LiDAR is also known as laser radar or LADAR. Its working principle is to emit a detection signal (laser beam) towards an object, and then compare the received signal (echo) reflected from the object with the transmitted signal. After appropriate processing, information about the object can be obtained. For example, parameters such as the object's distance, azimuth, height, speed, attitude, and even shape. A LiDAR can include a transmitting end and a receiving end. The transmitting end projects the emitted light from the transmitter onto the detection field of view after collimating and shaping it through a transmitting optical system. The receiving end receives the echo signal reflected from the object by the emitted light through a receiving optical system and a receiver. The transmitter can be deployed on a transmitting circuit board or a transmitting chip, and the receiver can be deployed on a receiving circuit board or a receiving chip. In the present disclosure, the LiDAR can be replaced by other active detection devices that measure information such as the position and speed of an object by emitting signals towards the object and receiving the signals reflected from the object.

[0043] In view of the problems described in the background art section, the present disclosure proposes an optical transceiver assembly for a LiDAR, including: a transmitting module, including: a transmitter including a plurality of lasers, the transmitter being configured to emit a first beam; and a transmitting lens for shaping the first beam and guiding the first beam to an external field of view; a receiving module, including: a receiving lens for transmitting the echo generated after the first beam is reflected by an object to a receiver; a receiver including a plurality of detectors, the receiver being configured to receive the echo and generate an electrical signal, wherein the difference in image height of the transmitting lens and the receiving lens at each field of view angle is less than a first threshold range, so that the overlap degree of the field of view of each laser and at least one corresponding detector is greater than a second set threshold. The plurality of lasers in the present disclosure can 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 can also include a laser emission circuit, etc. The plurality of detectors in the present disclosure can include one or more of single photon avalanche diodes (SPADs), avalanche photodiodes (APDs), silicon photomultipliers (SiPMs), or similar devices. The receiver in the present disclosure can also include a photodetection circuit, etc.

[0044] In the optical transceiver component for lidar according to the present disclosure, the ratio of the image height of the transmitting lens to the image height of the receiving lens at each field of view angle conforms to a first threshold range, so that the overlap degree between the field of view of each laser and the field of view of at least one corresponding detector is greater than a second set threshold. This can ensure transceiver alignment at each field of view angle even when the transmitter uses uniformly distributed lasers and the receiver uses uniformly distributed detectors (the echo formed after the light emitted by each laser is reflected by an object can reach the corresponding detector).

[0045] See Figures 1 to 3 。 Figure 1 FIG. is a schematic block diagram of an optical transceiver component 100 for lidar according to an exemplary embodiment of the present disclosure. Figure 2 Several examples of area array lasers are shown. Figure 3 An example of an area array detector is shown.

[0046] The optical transceiver component 100 for lidar may include a transmitting module 110 and a receiving module 120. The transmitting module may include a transmitter 111 and a transmitting lens 112. The transmitter 111 may include a plurality of lasers configured to generate a first light beam, and the transmitting lens 112 may be configured to shape the first light beam and direct the first light beam to an external field of view. The detection range of the first light beam in space after being shaped and directed by the transmitting lens 112 forms the transmitting field of view of the transmitting module 110. The receiving module 120 may include a receiver 121 and a receiving lens 122. The receiving lens 122 may transmit the echo generated after the first light beam is reflected by an object to the receiver 121. The receiver 121 may include a plurality of detectors configured to receive the echo and generate an electrical signal. The spatial range that the receiver 121 can detect through the receiving lens 122 forms the receiving field of view of the receiving module 120. The receiving field of view and the transmitting field of view should correspond to each other: the field of view of each laser corresponds to the field of view of at least one detector, so that at least part of the first light beam emitted by each laser can return to the corresponding detector after being reflected by an object in space.

[0047] In some embodiments of the present application, the transmitter 111 may include an area array laser (such as Figure 2 shown), and the receiver 121 may include an area array detector (such as Figure 3As shown). The area array laser can be a laser array arranged in two dimensions, or a laser array arranged in one dimension. The individual lasers in the area array laser can be configured to emit light in time (for example, in sequence), or can also be configured to emit light simultaneously. The first light beam emitted by each laser in the area array laser forms a FOV after being collimated and guided by the transmitting lens 112. Within the FOV range, if an object that can reflect light appears, the echo formed after the first light beam is reflected by the object is received by the receiving lens 122, and is converged on the corresponding detector of the area array detector in the corresponding field of view through the receiving lens 122, forming the entire detection circuit of the laser radar. It should be noted that the corresponding relationship between such lasers and detectors can be that the light spot emitted by each laser 11 corresponds to the FOV of a single detector 21 (such as Figure 4 As shown), it can also be that the light spot emitted by each laser 11 corresponds to the FOV of multiple detectors 21 (as shown Figure 5 Or as shown in 6), the light spots emitted by multiple lasers may correspond to the FOV of one detector, or the light spots emitted by multiple lasers may correspond to the FOVs of multiple detectors.

[0048] In an embodiment of the present disclosure, the transmitting lens 112 can be configured to expand the transmitting field of view of the transmitter 111, and the receiving lens 122 can be configured to expand the receiving field of view of the receiver 121. It is understandable that 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 cause 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 is distorted and the other lens is not distorted), it may cause the echo formed by the first light beam emitted by part of the laser being reflected by the object to be unable to return to the corresponding 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 corresponding 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 array laser 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 chip-based transceiver, the transmitting / receiving devices have become integrated devices, and the non-uniform device arrangement is not suitable for the on-chip system. 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.

[0049] 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. The transmitting lens 112 and the receiving lens 122 having the same f-θ distortion means that the ratio of the image height of the transmitting lens to the image height of the receiving lens at each field angle is the same or similar and 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 each laser and the field of view of at least one detector corresponding thereto can substantially overlap. For detection to be achieved, it is only necessary that the field of view of each laser and the field of view of at least one detector corresponding thereto can overlap, and the overlap degree is greater than a set threshold. In this case, it is not necessary for the transmitting lens 112 and the receiving lens 122 to have exactly the same f-θ distortion, but similarity is sufficient. The transmitting lens 112 and the receiving lens 122 having similar f-θ distortion means that the ratio of their image heights at each field angle is within a first threshold range, so that the overlap degree of the field of view of each laser and the field of view of at least one detector corresponding thereto can be greater than a second set threshold. As an example, the second set threshold can be between 50% and 90%, such as 50%, 60%, 80% or 90%. The value of the first threshold range is related to the focal lengths of the transmitting lens and the receiving lens.

[0050] In some embodiments of the present disclosure, the focal lengths of the transmitting lens 112 and the receiving lens 122 can be the same or different, which can be adjusted according to the sizes of the transmitter 111 and the receiver 121, as long as it can be ensured that the aforementioned transmitting lens 112 and receiving lens 122 adopt the same or similar f-θ distortion so that the overlap degree of the field of view of each laser and the field of view of at least one detector corresponding thereto can be greater than the second set threshold. For example, the transmitting lens 112 and the receiving lens 122 can adopt the same design, or for an existing transmitting lens (or receiving lens), the receiving lens (or transmitting lens) can be redesigned and the f-θ distortion curve of the lens can be adjusted to be the same or similar to that of the transmitting lens (or receiving lens) by changing the material, curvature, thickness, spacing, etc. of the lenses in the lens.

[0051] In some embodiments of the present disclosure, the optical transceiver module 100 may employ a uniformly arranged laser array and a uniformly arranged 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 the receiver 121) includes uniformly distributed lasers (or detectors) and the design of the transmitting lens 112 (or the receiving lens 122) is completed for the desired transmission field of view (or reception field of view), the focal length and the distortion curve of the transmitting lens 112 (or the receiving lens 122) are fixed, and the image height of the transmitting lens 112 (or the receiving lens 122) corresponding to each field of view angle θ is determined. In this case, in order to align the field of view of the lasers with the field of view of the corresponding detectors, for example, the laser beam emitted by a laser passes through the transmitting lens 112 corresponding to a certain field of view angle θ 0 , and the echo of the beam reflected by the object needs to pass through the receiving lens 122 to reach the corresponding detector. To achieve this, the receiving lens 122 (or the transmitting lens 112) needs to be designed such that the image height of the laser beam (at the θ 0 angle) in the receiving lens 122 (or the transmitting lens 112) has a corresponding relationship with the size of the detector (or the laser). To ensure that the field of view of each laser can be aligned with the field of view of the corresponding detector, the ratio of the image heights of the transmitting lens 112 and the receiving lens 122 at each field of view angle needs to meet the 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 sizes of the lasers and the detectors, the lasers and the detectors can be exactly aligned. However, since both the lasers and the detectors 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 each field of view angle within the first threshold range can ensure that the overlap degree between the field of view of each laser and the field of view of at least one corresponding detector can be greater than the second set threshold. To achieve the above purpose, the receiving lens 122 and the transmitting lens 112 need to have the same or similar f-θ distortion curves, so that the fields of view of the lasers can be respectively aligned with the fields of view of the corresponding detectors when both the transmitter 111 and the receiver 121 use uniformly distributed optoelectronic devices (lasers and detectors).

[0052] In an embodiment of the present disclosure, the transmitting lens 112 may be configured to expand the transmitting field of view of the transmitter 111 such that the field of view (FOV) of the transmitting module 110 is greater than or equal to 140°. Meanwhile, the receiving lens 122 may be configured to expand the receiving field of view of the receiver 121 such that the FOV of the receiving module 120 is greater than or equal to 140°. The focal lengths of the transmitting lens 112 and the receiving lens 122 may both be less than or equal to 16 mm. Compared with the solutions that use moving components to rotate the optical transceiver assembly or use scanning devices to change the propagation direction of the first light beam to achieve a larger FOV, the present disclosure uses a lens with an expanded field of view to replace the moving components or scanning devices to implement a lidar with an ultra-large field of view, which can reduce the size requirements for optoelectronic devices in the lidar while expanding the FOV of the lidar. In addition, it can also eliminate the additional costs brought by the moving components or scanning devices. It should be noted that the field of view (FOV) of the transmitting module 110 being greater than or equal to 140° means that at least one of the horizontal field of view and the vertical field of view of the transmitting module 110 is greater than or equal to 140°. The field of view (FOV) of the receiving module 120 being greater than or equal to 140° means that at least one of the horizontal field of view and the vertical field of view of the receiving module 120 is greater than or equal to 140°.

[0053] The focal lengths, field of view angles, and device sizes of the transmitting end (transmitting module 110) and the receiving end (receiving module 120) can be represented by the following formulas:

[0054]

[0055] θ Tx =θ Rx

[0056] Wherein, f Rx is the focal length of the receiving end, f Tx is the focal length of the transmitting end, θ Rx is the field of view angle of the receiving end, θ Tx is the field of view angle of the transmitting end, L Rx is the detector size, L Tx is the laser size.

[0057] According to the above formula, it can be known that when the FOV is fixed, the size of the laser or detector is related to the focal length of the corresponding transmitting lens 112 or receiving lens 122. For the receiving end, since each 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. Therefore, the overall size of the detector array is relatively large. If the focal lengths of the transmitting end and the receiving end are the same, it will lead to a relatively large size of the laser array at the transmitting end, which is not conducive to cost control and yield improvement. Therefore, in an alternative embodiment, it can be designed such that the focal length of the transmitting lens 112 is less than the focal length of the receiving lens 122, thereby reducing the size of the area array laser. In this way, the size of the transmitter 111 can be smaller than the size of the receiver 112.

[0058] In some embodiments of the present disclosure, the field of view (FOV) of the transmitting module 110 may be greater than or equal to 140° in a first direction, and is not limited in a second direction different from the first direction. In some other embodiments of the present disclosure, the field of view (FOV) of the transmitting module 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.

[0059] In some embodiments of the present disclosure, when both the horizontal field of view and the vertical field of view of the transmitting module 110 are greater than 140°, considering the effective isolation between the transmitter and the receiver, at least one of the horizontal field of view and the vertical field of view of the transmitting module 110 needs to be less than 180°. Similarly, when both the horizontal field of view and the vertical field of view of the receiving module 120 are greater than 140°, at least one of the horizontal field of view and the vertical field of view of the receiving module 120 needs to be less than 180°. If the horizontal field of view of the transmitting module 110 and the receiving module 120 exceeds 180°, then the transmitting lens 112 and the receiving lens 122 may be arranged vertically, as Figure 7 shown; if the vertical field of view of the transmitting module 110 and the receiving module 120 exceeds 180°, then the transmitting lens 112 and the receiving lens 122 may be arranged horizontally, as Figure 8 shown.

[0060] In some embodiments of the present disclosure, the transmitting lens 112 may be designed with all glass or a combination of glass and plastic. The number of lenses usually increases as the FOV of the lens increases. The transmitting lens 112 may include a front optical group and a rear optical group. The front optical group may be configured to expand the field of view (i.e., compress the large field of view angle of the object space to the field of view range required by a normal lens), and the rear optical group may be configured to shape (e.g., collimate) the laser beam emitted by the transmitting chip 111. The front optical group and the rear optical group together provide the focal length required by the transmitting lens 112.

[0061] To provide better field-of-view compression, that is, to enable the emission module 110 to have a larger FOV, the emission lens 112 includes at least a first meniscus lens on the light-emitting side as a component in the front optical group. The first meniscus lens can expand the emission field of view of the emitter 111, as Figure 9 shown. The first meniscus lens 91 may have a negative focal power, thereby shortening the overall focal length of the emission lens 112. As shown in the figure, the emission lens 112 further includes a rear optical group 92, and the rear optical group 92 is configured to shape (e.g., collimate) the first light beam emitted by the emitter 111.

[0062] Similarly, to provide better field-of-view compression, that is, to enable the receiving module 120 to have a larger FOV, the receiving lens 122 may at least include a second meniscus lens on the light-incident side as a component in the front optical group. The second meniscus lens can expand the receiving field of view of the receiver 121, as Figure 10 shown. The second meniscus lens 101 may have a negative focal power, thereby shortening the overall focal length of the receiving lens 122. As shown in the figure, the emission lens 112 further includes a rear optical group 102, and the rear optical group 102 is configured to guide the echo to the receiver 121.

[0063] For a general distortion-free lens (focal length f), the relationship between the field-of-view angle θ and the image height h is h = f * tan(θ), and the angular resolution α of a single detector size x at the central field of view of the lens (focal length f) is approximately α ≈ x / f. From the above two formulas, it can be seen that when the single detector size is fixed, if a higher angular resolution is desired (i.e., the value of α is smaller), the larger the focal length f of the lens is better. At the same FOV size, the larger f is, the more significantly the image height h of its edge field of view will increase, that is, the required device size will increase accordingly, and the increase in device size means an increase in cost and a decrease in reliability.

[0064] As described above, the emission lens 112 and the receiving lens 122 of the present disclosure may have f-θ distortion, and the distortion curves of the emission lens 112 and the receiving lens 122 can be reasonably designed so that the distortion degree of the emission lens 112 and the receiving lens 122 at the edge of the field of view (corresponding to a larger field-of-view angle) is greater than that at the center of the field of view (corresponding to a smaller field-of-view angle). In this way, the image height at the edge of the lens can be quickly converged, and while meeting the requirements of the central field-of-view angular resolution and FOV size, the excessive device size can be avoided, and the angular resolution of the central field of view and the device size can be balanced.

[0065] On the other hand, since the sizes of the laser and the detector are generally uniform and uniformly arranged, the lens design of the present disclosure can cause larger distortion at the edge of the field of view to reduce the device size. Therefore, the larger the field of view angle interval corresponding to the detector closer to the edge of the field of view, that is, the sparser the corresponding point cloud. Since lidar usually cares more about the detection in the central field of view, the optical transceiver component 100 with a larger FOV just takes advantage of this point and can obtain a point cloud with a large FOV, dense central field of view, and sparse edge field of view. In this way, the angular resolution in the central region of the lidar can be higher, and more refined target recognition and measurement can be provided for the central region.

[0066] As Figure 9 shown, the transmitting lens 112 can distort the uniformly distributed light-emitting surface of the laser into a structure that is dense in the center and sparse at the edges. Specifically, the lasers in the edge channels can correspond to larger field of view angles in space, while the lasers in the central channels are less affected by the distortion of the transmitting lens 112, and more pixels can be applied to the central field of view, and a higher pixel density can be maintained in the central field of view, realizing a relatively high resolution in the central field of view. In this way, when the size of the laser array in the transmitter 111 is small, the transmitting module 110 can simultaneously achieve coverage of a large FOV and encryption of its central field of view. For example, the size of the laser array can be less than 500 mm 2 , less than 400 mm 2 , less than 300 mm 2 , less than 200 mm 2 , less than 100 mm 2 or smaller. Optionally, the concave surface of the first meniscus lens 91 can face the transmitter 111.

[0067] As Figure 10 shown, the receiving lens 122 can distort the uniformly distributed photosensitive surface of the detector into a structure that is dense in the center and sparse at the edges. Specifically, the detectors in the edge channels can correspond to larger field of view angles in space, while the detectors in the central channels are less affected by the distortion of the receiving lens 122, and more pixels can be applied to the central field of view, and a higher pixel density can be maintained in the central field of view, realizing a relatively high resolution in the central field of view. In this way, when the size of the detector array in the receiver 121 is small, the receiving module 120 can simultaneously achieve coverage of a large FOV and encryption of its central field of view. For example, the size of the detector array can be less than 500 mm 2 , less than 400 mm 2 , less than 300 mm 2 , less than 200 mm 2 , less than 100 mm 2 or smaller. Optionally, the concave surface of the second meniscus lens 101 can face the receiver 121.

[0068] In some embodiments of the present disclosure, the transmitting lens 112 may be configured to expand the transmitting field of view of the transmitter 111 such that the field of view (FOV) of the transmitting module 110 is greater than or equal to 150°. Meanwhile, the receiving lens 122 may be configured to expand the receiving field of view of the receiver 121 such that the FOV of the receiving module 120 is greater than or equal to 150°, and the focal lengths of the transmitting lens 112 and the receiving lens 122 may both be less than or equal to 10 mm.

[0069] In some embodiments of the present disclosure, the transmitting module may employ various types of lasers, including but not limited to vertical cavity surface emitting lasers (VCSELs), edge emitting lasers (EELs), etc.; the receiving module may employ various types of detectors, including but not limited to single photon avalanche diodes (SPADs), avalanche photodiodes (APDs), silicon photomultipliers (SiPMs), etc.

[0070] According to another exemplary embodiment of the present disclosure, the present disclosure also provides an optical transceiver assembly for a lidar, which includes: a transmitter including a plurality of lasers, the transmitter being configured to emit a first light beam; a receiver including a plurality of detectors, the receiver being configured to receive an echo generated after the first light beam is reflected by an object and generate an electrical signal; a beam splitting device configured to guide and separate the first light beam and the echo; a transceiver lens configured to shape the first light beam and guide the first light beam to an external field of view, and transmit the echo to the receiver; the ratio of the transmitted optical path image height to the received optical path image height of the transceiver lens at each field of view angle conforms to a first threshold range such that the overlap degree of the field of view of each laser and the field of view of at least one corresponding detector is greater than a second set threshold. The transmitted optical path image height may refer to the distance between the center of the laser emitting the first light beam having a certain field of view angle and the principal optical axis of the transmitted optical path. The received optical path image height may refer to the distance between the center of the detector receiving the echo having a certain field of view angle and the principal optical axis of the received optical path. Wherein, since the beam splitting device can guide and separate the first light beam and the echo, it may cause the transmitted optical path or the received optical path to be deflected. Therefore, if the transmitted optical path (or the received optical path) is deflected by the beam splitting device, the aforementioned principal optical axis may be the principal optical axis of the transmitted optical path (or the received optical path) after deflection. If the transmitted optical path (or the received optical path) is not deflected by the beam splitting device, the aforementioned principal optical axis may be the principal optical axis of the undeflected transmitted optical path (or the received optical path).

[0071] Figure 11 A schematic diagram showing an optical transceiver assembly 1100 for a lidar according to another exemplary embodiment of the present disclosure. Some details of the optical transceiver assembly 1100 are the same as those of the optical transceiver assembly 100 described above, and will not be repeated here. The following mainly describes the differences of the optical transceiver assembly 1100. Figures 1 - 10 The description of the optical transceiver assembly 100 above is the same, and will not be repeated here. The following mainly describes the differences of the optical transceiver assembly 1100.

[0072] The optical transceiver component 1100 for lidar may include a transmitter 1110, a receiver 1120, a beam splitter device 1130, and a transceiver lens 1140. The transmitter 1110 may include a plurality of lasers configured to emit a first beam. The receiver 1120 may include a plurality of detectors and be configured to receive the echo generated after the first beam is reflected by an object and generate an electrical signal.

[0073] Compared with the optical transceiver component 100 having a paraxial optical path, the optical transceiver component 1100 has a coaxial optical path, and its transmission optical path and reception optical path at least partially coincide. In this embodiment, the optical transceiver component 1100 includes a beam splitter device 1130 and a transceiver lens 1140 that simultaneously serves as a transmission optical path lens and a reception optical path lens. The beam splitter device 1130 may be configured to guide and separate the first beam and the echo. After the first beam is shaped and guided by the transceiver lens 1140, its detection range in space forms the transmission field of view of the optical transceiver component 1100. The spatial range that the receiver 1120 can detect through the transceiver lens 1140 forms the reception field of view of the optical transceiver component 1100. As Figure 11 shown, the beam splitter device 1130 may reflect at least a part of the first beam emitted by the transmitter 1110 for transmission to the transceiver lens 1140, and the transceiver lens 1140 is configured to shape the first beam and guide the first beam to the external field of view. The transceiver lens 1140 may also guide the echo after the first beam is reflected by an object to the beam splitter device 1130, and the beam splitter device 1130 may transmit at least a part 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 may also be interchanged, and in this case, the beam splitter device 1130 may transmit at least a part of the first beam emitted by the transmitter 1110 for transmission to the transceiver lens 1140, and may reflect at least a part of the echo and transmit it to the receiver 1120.

[0074] In the optical transceiver component 1100, the transmitter 111 and the receiver 121 of the optical transceiver component 1100 may adopt uniformly distributed optoelectronic devices (lasers and detectors). In some embodiments of the present disclosure, the same transceiver lens 1140 may be adopted at the transmitting end and the receiving end (as Figure 11 shown), and the focal lengths of the transmitting end and the receiving end are the same. Therefore, the size of the transmitter 1110 may be matched with the size of the receiver 1120 so that the overlap degree between the field of view of each laser and the field of view of at least one corresponding detector is greater than a second set threshold, which realizes that the field of view of each laser is respectively aligned with the field of view of the corresponding detector. As an example, the second set threshold may be between 50% and 90%, such as 50%, 60%, 80%, or 90%.

[0075] In some embodiments of the present disclosure, the transmitting end and the receiving end of the optical transceiver module 1100 may also have different focal lengths. Refer to Figures 12 - 14 , which shows several embodiments in which the transmitting end and the receiving end of the optical transceiver module 1100 have different focal lengths.

[0076] As Figure 12 shown, 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 optical path and the receiving optical path, and 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, and the first lens 1141 forms the receiving optical path lens.

[0077] As Figure 13 shown, 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 optical path and the receiving 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 forms the transmitting optical path lens, and the first lens 1141 and the third lens 1143 form the receiving optical path lens.

[0078] As Figure 14 shown, 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 optical path and the receiving optical path, 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, and the first lens 1141 and the third lens 1143 form the receiving optical path lens.

[0079] In the above embodiments, since the transmitting optical path and the receiving optical path have different lens compositions, there may be a situation of mismatched distortion, which may cause the echo formed by the reflection of the first beam emitted by some lasers by an object not to return to the corresponding detector, that is, there is a mismatch between the light-emitting surface and the photosensitive surface. In this regard, the transceiver lens can be configured such that the ratio of the image height of the transmitting optical path to the image height of the receiving optical path at each field of view angle conforms to a first threshold range, so that the overlap degree between the field of view of each laser and the field of view of at least one corresponding detector is greater than a second set threshold. The image height of the transmitting optical path may refer to the distance between the center of the laser emitting the first beam with a certain field of view angle and the principal optical axis of the transmitting optical path. The image height of the receiving optical path may refer to the distance between the center of the detector receiving the 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 field of view of each laser and the field of view of at least one corresponding detector can be substantially overlapped. However, for detection to be achieved, it is only necessary that the field of view of each laser and the field of view of at least one corresponding detector can overlap, and the overlap degree is greater than the set 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 range is related to the focal lengths of the transmitting optical path lens and the receiving optical path lens.

[0080] In an embodiment of the present disclosure, the transceiver lens 1140 can be configured to expand the transmitting field of view of the transmitter 1110 and the receiving field of view of the receiver 1120 such that the field of view angle (FOV) 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 with the scheme of using moving parts to rotate the optical transceiver assembly or using scanning devices to change the propagation direction of the first beam to achieve a larger FOV, the present disclosure contemplates using a lens with an expanded field of view angle to replace the moving parts or scanning devices to implement a lidar with an ultra-large field of view, which can reduce the size requirements for the optoelectronic devices in the lidar while expanding the FOV of the lidar, and can also eliminate the additional costs brought by the 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 incident direction of the first beam, and the convex surface can face the incident direction 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 referred to above Figure 9 and Figure 10 described. Optionally, the meniscus lens can have a negative optical power, thereby shortening the overall focal length of the transceiver lens 1140.

[0081] In some embodiments of the present disclosure, the transceiver lens 1140 may be configured to expand the transmission field of view of the transmitter 1110 and the reception field of view of the receiver 1120 such that the field of view (FOV) of the optical transceiver assembly is greater than or equal to 150°, and the focal length of the transceiver lens 1140 may be less than or equal to 10 mm.

[0082] In some embodiments, the beam splitter device 1130 may include a semi-transmissive and semi-reflective mirror that transmits at least a portion of the first beam and reflects at least a portion of the echo, or the semi-transmissive and semi-reflective mirror reflects at least a portion of the first beam and transmits at least a portion of the echo. In some embodiments, the beam splitter device 1130 may include a mirror with a small hole, at least a portion of the first beam may be transmitted through the small hole in the mirror to the transceiver lens, and at least a portion of the echo may be reflected by the mirror to the receiver 1120. In some embodiments, the beam splitter device 1130 may include a small mirror, at least a portion of the first beam may be reflected by the small mirror to the transceiver lens 1140, and at least a portion of the echo may be transmitted through the periphery of the small mirror to the receiver.

[0083] In an alternative embodiment of the present disclosure, in order to reduce energy loss, the optical transceiver assembly 1100 may adopt a polarization beam splitting method. Specifically, referring to Figure 15 , the beam splitter device may include a polarization beam splitter 1131 for reflecting P-polarized light and transmitting S-polarized light, and the beam splitter device may further include a quarter-wave plate 1132 located between the polarization beam splitter 1131 and the transceiver lens 1140. In this alternative embodiment, the polarization state of the first beam emitted by the transmitter 1110 may be configured as P-polarized, that is, the transmitter 1110 emits P-polarized light; the P-polarized light may be reflected by the beam splitter device 1130 to pass through the quarter-wave plate 115 and the transceiver lens 1140 and be guided to the external field of view, and the echo passes through the transceiver lens 1140 and the quarter-wave plate 1150 and returns to the beam splitter device 1130. Since the P-polarized light passes through the quarter-wave plate 1150 twice and is converted into S-polarized light, the echo as S-polarized light is transmitted by the beam splitter device 1130 and transmitted to the receiver 1120. It should be noted that in some embodiments, the polarization beam splitter 1131 may also transmit P-polarized light and reflect S-polarized light; in this case, Figure 12 the positions of the transmitter 1110 and the receiver 1120 in

[0084] According to another exemplary embodiment of the present disclosure, a lidar is further provided.

[0085] As Figure 16 shown, the lidar 1600 may include the optical transceiver assembly 100 / 1100 and the controller 200 described above.

[0086] The optical transceiver module 100 / 1100 can provide a first light beam 1001 into a target space to illuminate an object 20 in the space. At least part of the first 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 optical transceiver module 100 / 1100.

[0087] The controller 200 is connected to the optical transceiver module 100 and configured to control the emitter to emit the first light beam; and receive and process the electrical signal generated by the receiver to calculate at least one of the distance and reflectivity of the object 20.

[0088] In some embodiments of the present disclosure, the controller 200 may also be configured to control multiple lasers of the emitter to emit light simultaneously or time-divisionally.

[0089] According to another exemplary embodiment of the present disclosure, a terminal device is further provided. The terminal device may include the lidar 1600 as described above. The terminal device may be a vehicle (such as a smart car), a surveying and mapping device, an aircraft (such as a drone), a ship, etc.

[0090] So far, the optical transceiver module, the lidar including it, and the terminal device according to the present disclosure have been described. The optical transceiver module of the present disclosure allows for a uniformly distributed emitter / receiver design to be adopted when using a transceiver lens with distortion.

[0091] Optionally, the present disclosure may adopt an F-theta lens with an enlarged FOV as the transceiver lens. Since it has distortion itself, the distortion curves of the emission lens and the receiving lens can be reasonably designed so that the distortion degree at the edge of the field of view (corresponding to a larger field of view angle) is greater than that at the center of the field of view (corresponding to a smaller field of view angle). In this way, the image height can converge quickly at the edge of the lens, and while meeting the requirements of the central field of view angle resolution and FOV size, the device size can be avoided from being too large, and the angular resolution of the central field of view and the device size can be balanced.

[0092] Secondly, the lidar using the optical transceiver module of the present disclosure 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 generally the size of the detector is uniform and uniformly arranged. The lens design of the present disclosure allows for a larger distortion at the edge of the field of view (to reduce the device size). Therefore, the larger the field of view angle interval corresponding to the detector closer to the edge of the field of view, that is, the sparser the corresponding point cloud. And lidar usually pays more attention to the detection situation in the central field of view. So the optical transceiver module of the present disclosure just takes advantage of this point, and can enable the lidar to obtain a large FOV and a point cloud that is dense in the central field of view and sparse at the edge of the field of view.

[0093] 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, many modifications can be made to adapt a particular situation or material to the teachings of various embodiments of the present disclosure without departing from the scope of the present disclosure. Although the dimensions and types of the materials described herein are used to define the parameters of various embodiments of the present disclosure, the various embodiments are not meant to be restrictive but are exemplary embodiments. Many other embodiments will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the various embodiments of the present disclosure should be determined with reference to the appended claims and the full scope of equivalents to which these claims are entitled.

Claims

1. An optical transceiver component for a lidar, comprising: A transmitting module, comprising: A transmitter, comprising a plurality of lasers, the transmitter being configured to emit a first light beam; and A transmitting lens, configured to shape the first light beam and direct the first light beam to an external field of view; A receiving module, comprising: A receiving lens, configured to transmit an echo generated after the first 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, The ratio of the image height of the transmitting lens to the image height of the receiving lens at each field of view angle conforms to a first threshold range, so that the overlap degree of the field of view of each laser and the field of view of at least one corresponding detector is greater than a second set threshold.

2. The optical transceiver component according to claim 1, wherein, The second set threshold is 50%, 60%, 80% or 90%.

3. The optical transceiver component according to claim 1, wherein, The field of view angles (FOV) of both the transmitting module and the receiving module are greater than or equal to 140°, and the focal lengths of both the transmitting lens and the receiving lens are less than or equal to 16 mm.

4. The optical transceiver component according to claim 3, wherein, The transmitting lens at least includes a first meniscus lens located on the light-emitting side, the concave surface of the first meniscus lens faces the transmitter, and the first meniscus lens has a negative optical power.

5. The optical transceiver component according to claim 3, wherein, 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 component according to claim 3, wherein, The horizontal field of view angle and / or the vertical field of view angle of the transmitting module are less than 180°, and the horizontal field of view angle and / or the vertical field of view angle of the receiving module are less than 180°.

7. The optical transceiver component according to claim 6, wherein, The horizontal field of view angles of both the transmitting module and the receiving module are greater than 180°, and the transmitting lens and the receiving lens are arranged vertically.

8. The optical transceiver component according to claim 6, wherein, The vertical field of view angles of both the transmitting module and the receiving module are greater than 180°, and the transmitting lens and the receiving lens are arranged horizontally.

9. The optical transceiver component according to claim 3, wherein, The distortion degree of the transmitting lens and the receiving lens at the edge of the field of view is greater than the distortion degree at the center of the field of view.

10. The optical transceiver component according to claim 3, wherein, The field of view angles (FOV) of both the transmitting module and the receiving module are greater than or equal to 150°, and the focal lengths of both the transmitting lens and the receiving lens are less than or equal to 10 mm.

11. The optical transceiver component according to claim 1, wherein, The focal length of the transmitting lens is less than the focal length of the receiving lens.

12. The optical transceiver component according to claim 11, wherein, The size of the transmitter is less than the size of the receiver.

13. An optical transceiver component for a lidar, include: a transmitter, comprising a plurality of lasers, the transmitter configured to emit a first light beam; A receiver, comprising a plurality of detectors, wherein the receiver is configured to receive an echo generated after the first light beam is reflected by an object and generate an electrical signal; A beam splitter configured to guide and separate the first light beam and the echo; a transceiver lens configured to shape the first light beam and direct the first light beam to an external field of view, and transmit the echo to the receiver; The ratio of the image height of the transmitting light path to the image height of the receiving light path of the transceiver lens at each field of view angle meets the first threshold interval, so that the overlap between the field of view of each laser and the field of view of at least one corresponding detector is greater than a second set threshold.

14. The optical transceiver assembly according to claim 13, It is characterized in that The field of view (FOV) 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, It is characterized in that The transceiver lens at least includes a meniscus lens, a concave surface of the meniscus lens faces the incident direction of the first light beam, and a convex surface of the meniscus lens faces the incident direction of the echo.

16. The optical transceiver assembly according to claim 14, It is characterized in that The field of view (FOV) 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. A laser radar, include: The optical transceiver assembly according to any one of claims 1 to 16; as well as Controller, configured as: Controlling the emitter to emit the first light beam; and The electrical signal generated by the receiver is received and processed to calculate at least one of a distance and a reflectivity of the object.

18. The laser radar according to claim 17, It is 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.

19. A terminal device, comprising the laser radar as claimed in claim 17 or 18.

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