Receiving module, radar, terminal, and vehicle end

Abstract

A receiving module (200), a radar, a terminal, and a vehicle end, relating to the technical field of laser radars. The receiving module (200) comprises an optical element and a detector (201), and the receiving module (200) is used for receiving a linear light beam extending in a first direction. The optical element is used for astigmatism of a first light beam in a second direction and / or field curvature of the first light beam. The detector (201) receives, by means of a plurality of monitoring areas, a light beam passing through the optical element, and the detector (201) is located at a target focal plane of the optical element. The dynamic range of imaging can be ensured by diffusing the first light beam in the second direction by means of astigmatism and diffusing a light beam at an edge field of view by means of field curvature. The detector (201) is placed at the target focal plane of the optical element, so that on the basis of configuration of pixels on the detector (201), the receiving module (200) has the capability of high-resolution reception. Therefore, the optical element provided in the solution does not involve a complex manufacturing process, has a simple structure, involves low manufacturing costs, and can achieve low-cost design of high-resolution laser radars.

Description

Receiving module, radar, terminal and vehicle terminal

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on January 19, 2024, with application number 202410082985.0, and priority to the Chinese patent application entitled “A Receiving Module, Radar, Terminal and Vehicle Terminal”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of laser radar technology, and in particular to a receiving module, radar, terminal and vehicle terminal. Background Art

[0003] Lidar, also known as optical radar, is a light detection and ranging (Lidar) system. Using light as its detection medium, Lidar utilizes the emission and reception of lasers to detect targets, for example, to measure distance, velocity, or azimuth.

[0004] LiDAR scanning methods include one-dimensional scanning and two-dimensional scanning. One-dimensional scanning, based on diffractive optical elements (DOEs), improves detection and resolution of regions of interest (ROIs). Two-dimensional scanning requires controlling the scanning mirror to perform non-uniform motion in two dimensions, enabling high-resolution detection of the ROI.

[0005] Since the manufacturing process of the above-mentioned DOE is difficult, the temperature reliability is low, and the control logic of the above-mentioned two-dimensional scanning method is complex, achieving high-resolution reception of the laser radar through a low-cost and simple control logic method is an urgent problem that needs to be solved. Summary of the Invention

[0006] This application provides a receiving module, radar, terminal, and vehicle terminal, relating to the field of laser radar technology. The receiving module is based on a one-dimensional scanning architecture of a line spot to achieve high-resolution reception of the laser radar.

[0007] In a first aspect, the present application provides a receiving module comprising: an optical element and a detector. The receiving module is used to receive a linear light beam (first light beam) extending along a first direction. The optical element is used to perform astigmatism on the first light beam in a second direction, and / or to perform field curvature on the first light beam. The detector receives the light beam passing through the optical element through a plurality of monitoring areas, the plurality of monitoring areas including different pixel shapes, and the detector is located at the target focal plane of the optical element. Furthermore, the first direction and the second direction are perpendicular to each other.

[0008] The receiving module provided in the present application is used to receive a linear light beam (referred to as the first light beam for short) extending along a first direction, so that the receiving module can be applied to a one-dimensional scanning architecture of a linear light spot. The optical element performs astigmatism on the first light beam in the second direction, which can cause the first light beam to diffuse in the second direction. The optical element performs field curvature on the first light beam, which can cause the first light beam to diffuse in the first direction and the second direction. It can be understood that the diffusion intensity of the astigmatism on the first light beam is proportional to the distance of the light spot from the optical axis. For example, the light spot near the optical axis (center field of view) is weakest affected by the astigmatism, and the light spot at the edge field of view is strongest affected by the astigmatism. The diffusion intensity of the field curvature on the first light beam is proportional to the distance of the light spot from the optical axis. For example, the light spot near the optical axis is basically not affected by the field curvature. For another example, the light spot located at the edge field of view is affected by the field curvature and will produce a large range of diffusion in the first direction and the second direction. It can be seen that the diffusion intensity of the first light beam of the optical element at different positions is also different. Accordingly, the detector receives the light beam passing through the optical element through multiple monitoring areas, and the multiple monitoring areas include different pixel shapes, so that the detector can accurately receive the light beam passing through the optical element and use it for subsequent imaging.

[0009] Because the detector is located at the target focal plane of the optical element, the light spot near the optical axis in the first direction does not diffuse. Furthermore, because the linear beam from the detector extends along the first direction, the receiving module achieves high-resolution reception. Furthermore, the optical element is used to treat astigmatism and / or field curvature of the linear beam, eliminating the need for complex manufacturing processes, resulting in a simple structure and low manufacturing cost.

[0010] In summary, the receiving module provided by this application utilizes a one-dimensional scanning structure of a linear light spot, enabling high-resolution LiDAR reception and a low-cost design for high-resolution LiDAR. Furthermore, because the receiving module provided by this application is based on a one-dimensional scanning structure of a linear light spot and does not require complex optical components, it also facilitates the miniaturization of high-resolution LiDAR designs.

[0011] In a possible implementation, the plurality of monitoring areas include a first monitoring area and a second monitoring area. In the first direction, a length of pixels in the first monitoring area is smaller than a length of pixels in the second monitoring area.

[0012] In the embodiment of the present application, in the first direction, the length of the pixels in the first monitoring area is smaller than the length of the pixels in the second monitoring area, so that the pixel density of the first monitoring area in the first direction is greater than that of the second monitoring area, so that the resolution of the corresponding imaging of the first monitoring area is higher than that of the second monitoring area.

[0013] Optionally, the first monitoring area is, for example, the monitoring area through which the optical axis of the optical element passes, or the monitoring area including the central field of view. The second monitoring area is, for example, the monitoring area farther from the optical axis of the optical element, or the monitoring area including the edge field of view.

[0014] Optionally, the first monitoring area is, for example, an ROI area, and the second monitoring area is, for example, another monitoring area other than the ROI area among the multiple monitoring areas. In the first direction, the pixel length of the ROI area is smaller than the pixel lengths of the other monitoring areas, so that the imaging corresponding to the ROI area has a high imaging resolution.

[0015] Optionally, in the first direction, the length of the light spot received in the first monitoring area is smaller than the length of the light spot received in the second monitoring area.

[0016] In another possible implementation, in the first direction, the length of pixels in the first monitoring area is greater than the length of pixels in the second monitoring area.

[0017] In the above embodiment, in the second direction, the pixel length of the first monitoring area is greater than the pixel length of the second monitoring area, so as to ensure the dynamic range of the imaging corresponding to the first monitoring area.

[0018] Optionally, the first monitoring area is, for example, an ROI area, and the second monitoring area is, for example, another monitoring area other than the ROI area among the multiple monitoring areas. In the second direction, the pixel length of the ROI area is greater than the pixel lengths of the other monitoring areas, thereby ensuring the dynamic range of the imaging corresponding to the ROI area.

[0019] Optionally, in the second direction, the length of the light spot received in the first monitoring area is greater than the length of the light spot received in the second monitoring area.

[0020] In another possible implementation, the areas of pixels in the first monitoring area and the second monitoring area are equal.

[0021] In the embodiment of the present application, the areas of the pixels in the first monitoring area and the second monitoring area are equal, which enables the areas (number) of light beams received by pixels in different monitoring areas to be equal, thereby ensuring that the dynamic ranges of the corresponding imaging in different monitoring areas are the same, thereby facilitating subsequent imaging processing (for example, stitching, fusion, encoding, etc.).

[0022] In another possible implementation, in the second direction, the length of pixels in the first monitoring area is equal to the length of pixels in the second monitoring area.

[0023] In the embodiment of the present application, in the second direction, the pixel length of the first monitoring area is equal to the pixel length of the second monitoring area, so that the imaging corresponding to the first monitoring area and the second monitoring area has a high dynamic range.

[0024] Optionally, in the second direction, the length of the light spot received in the first monitoring area is equal to the length of the light spot received in the second monitoring area.

[0025] In another possible implementation, the length a of the pixels in the first monitoring area in the first direction and the length b in the second direction satisfy the following relationship: b=L*a, where L is greater than or equal to 2.

[0026] In an embodiment of the present application, the length a of pixels in the first monitoring area in the first direction and the length b in the second direction satisfy the following relationship: b = L*a, where L is greater than or equal to 2. This allows the pixels in the first monitoring area to receive a linear light beam that is widely diffused in the second direction. For example, the pixels in the first monitoring area can receive a linear light beam that is acted upon by an astigmatism, a cylindrical lens, or a micro-cylindrical lens array, wherein the linear light beam extends along the first direction, and the astigmatism, cylindrical lens, or micro-cylindrical lens array is used to diffuse the linear light beam in the second direction.

[0027] Optionally, the above L equals 4, that is, b=4a.

[0028] Optionally, the length c of the pixels in the second monitoring area in the first direction and the length d in the second direction satisfy the following relationship: c=d.

[0029] Optionally, the areas of pixels in the first monitoring area and the second monitoring area are equal, that is, a×b=c×d.

[0030] In another possible implementation, the multiple monitoring areas include a third monitoring area, and the third monitoring area is covered by an obstruction.

[0031] In the embodiment of the present application, the plurality of monitoring areas include not only the first monitoring area and the second monitoring area, but also a third monitoring area. The third monitoring area is covered by an obstruction, which can block the light beam from being received by the third monitoring area, thereby reducing the introduction of interfering light beams and thus avoiding the introduction of background noise into the first monitoring area and the second monitoring area.

[0032] Optionally, the third monitoring area is shielded by screen printing, coating, electroplating or dispensing, so as to prevent the light beam from being received by the third monitoring area.

[0033] Optionally, the third monitoring area does not overlap with the first monitoring area and the second monitoring area.

[0034] In another possible implementation, the optical element is used to perform astigmatism on the first light beam in the second direction, and the optical element is used to perform field curvature on the first light beam.

[0035] In the embodiment of the present application, the optical element is capable of performing astigmatism and field curvature on the first light beam. The diffusion direction of the light beam due to astigmatism (the second direction) is perpendicular to the direction in which the first light beam extends (the first direction), which can cause the light beam near the optical axis of the optical element to diffuse over a large range in the second direction. The intensity of the light beam diffusion due to field curvature is proportional to the distance between the light beam and the optical axis. In addition, the diffusion effect of field curvature on the light beam is omnidirectional (the first direction and the second direction). Combined with the above description, the first light beam is affected by astigmatism and field curvature, and presents the following rules: 1. The light beam near the optical axis of the optical element will mainly be affected by astigmatism, resulting in a large range of diffusion in the second direction. 2. As the distance between the light beam and the optical axis of the optical element increases, the light beam is increasingly affected by the field curvature and astigmatism, so the light beam will be diffused to a certain extent in both the first direction and the second direction.

[0036] Optionally, by controlling the properties of astigmatism and field curvature, the degree of diffusion of the light beam near the optical axis of the optical element in the second direction can be greater than that of other light beams (in this case, the detector can be located between the meridional focal plane and the sagittal focal plane).

[0037] Alternatively, the receiving module provided in the embodiments of this application utilizes a one-dimensional scanning architecture based on a linear spot, achieving high resolution through optical properties such as astigmatism and field curvature. This eliminates the need for expensive optical components and complex control logic, effectively reducing production costs and volume.

[0038] In another possible implementation, the optical element is used to perform field curvature on the first light beam. A micro-cylindrical lens array is provided on the first monitoring area, and the micro-cylindrical lens array is used to diffuse the light beam passing through the optical element in the second direction.

[0039] In an embodiment of the present application, an optical element is used to perform field curvature on the first light beam, which can allow the diffusion intensity of the light beam to continuously increase as the distance between the light beam and the main optical axis of the optical element increases, thereby ensuring the dynamic range of the corresponding imaging of other monitoring areas (monitoring areas other than the first monitoring area). In addition, the optical element performs field curvature on the first light beam, which can also ensure that the light beam received by the first monitoring area is less diffused in the first direction, thereby ensuring that the imaging corresponding to the first monitoring area has high resolution. In an embodiment of the present application, a micro-column lens array is arranged on the first monitoring area, which can diffuse the light beam passing through the optical element in the second direction. Specifically, the micro-column lens array causes the light beam received by the first monitoring area to be diffused in the second direction, thereby ensuring the dynamic range of the corresponding imaging of the first monitoring area.

[0040] Optionally, by controlling the properties of the micro-cylindrical lens array and the field curvature, the diffusion degree of the light beam received by the first monitoring area in the second direction can be made greater than that of the light beams received by other monitoring areas.

[0041] Alternatively, the receiving module provided in the embodiments of this application utilizes a one-dimensional scanning architecture based on a linear spot, achieving high resolution through the field curvature of optical elements and a micro-cylindrical lens array. This eliminates the need for expensive optical components and complex control logic, effectively reducing production costs and volume.

[0042] In another possible implementation, the optical element is used to perform field curvature on the first light beam. The receiving module further includes a cylindrical lens disposed between the optical element and the detector, the cylindrical lens being used to diffuse the light beam passing through the optical element in the second direction.

[0043] In an embodiment of the present application, an optical element is used to perform field curvature on the first light beam, which can allow the diffusion intensity of the light beam to continuously increase as the distance between the light beam and the optical axis of the optical element increases, thereby ensuring the dynamic range of the corresponding imaging of other monitoring areas (monitoring areas other than the first monitoring area). In addition, the optical element performs field curvature on the first light beam, which can also ensure that the light beam received by the first monitoring area is less diffused in the first direction, thereby ensuring that the imaging corresponding to the first monitoring area has high resolution. In an embodiment of the present application, a cylindrical lens is provided between the optical element and the detector, which can diffuse the light beam passing through the optical element in the second direction, so that the light beam received by the first monitoring area is diffused in the second direction, thereby ensuring the dynamic range of the corresponding imaging of the first monitoring area.

[0044] Optionally, a cylindrical lens is provided between the optical element and the detector, so that the light beam received by the second monitoring area is diffused in the second direction, thereby improving the dynamic range of the imaging corresponding to the second monitoring area.

[0045] Alternatively, the receiving module provided in the embodiments of this application utilizes a one-dimensional scanning architecture based on a linear spot, achieving high resolution through the field curvature of optical elements and a cylindrical lens array. This eliminates the need for expensive optical components and complex control logic, effectively reducing production costs and volume.

[0046] In another possible implementation, the first direction depends on a target focal plane.

[0047] In the embodiment of the present application, the first direction depends on the target focal plane, so that the extension direction of the first light beam can be adjusted based on the target focal plane, which facilitates the flexible design of the emission module.

[0048] Optionally, the target focal plane is a meridional focal plane or a sagittal focal plane.

[0049] Optionally, when the optical element has no astigmatism, the target focal plane is the optimal focal plane.

[0050] Optionally, when the target focal plane is a meridional focal plane, the first direction is a vertical direction (a direction perpendicular to the horizon), and the second direction is a horizontal direction (a direction parallel to the horizon).

[0051] Optionally, when the target focal plane is a sagittal focal plane, the first direction is a horizontal direction and the second direction is a vertical direction.

[0052] Optionally, when the target focal plane is the optimal focal plane, the first direction can be any direction, for example, a horizontal direction or a vertical direction. The second direction can be perpendicular to the first direction. For example, the first direction is a vertical direction, and the second direction is a horizontal direction. The first direction is a horizontal direction, and the second direction is a vertical direction.

[0053] In another possible implementation, the number of detection units in a pixel depends on the area of ​​the detection unit, where the detection unit is the smallest unit for a detector to receive a light beam.

[0054] In the embodiment of the present application, the number of detection units in a pixel depends on the area of ​​the detection unit. For example, the number of detection units in a pixel is proportional to the area of ​​the detection unit. For another example, pixels of the same area include the same number of detection units.

[0055] In another possible embodiment, the detection unit includes one or more of the following: a single photon avalanche detector (SPAD), a silicon photomultiplier (SiPM), a multi-pixel photon counter (MPPC), a semiconductor avalanche photodiode (APD), or a "positive-intrinsic-negative" PIN diode.

[0056] In another possible implementation, the cylindrical lens may be integrated with the optical element.

[0057] In another possible implementation, the micro-cylindrical lens array may be embossed on a cover glass (CG).

[0058] In another possible implementation, the micro-cylindrical lens array and the detector may be integrated and packaged using micro-nano technology.

[0059] In a second aspect, the present application provides a detection device comprising a transmitting module and a receiving module. The transmitting module is configured to transmit a linear light beam, and the receiving module is configured to receive the linear light beam transmitted by an object. The receiving module comprises the receiving module described in the first aspect and any possible embodiment described above.

[0060] In the embodiments of the present application, the transmitting module is used to transmit a linear light beam and perform a one-dimensional scan of the detected object, without the need for complex control logic. In combination with the first aspect and any possible embodiment described above, this enables high-resolution reception of the detection device and a low-cost design of the detection device. Furthermore, because the receiving module provided in this application is based on a one-dimensional scanning structure of a linear light spot and does not require complex optical elements, it is also beneficial to achieve a miniaturized design of the detection device.

[0061] In one possible embodiment, the receiving module includes an optical element and a detector. When the detector is located in the meridional focal plane of the optical element, the linear beam emitted by the transmitting module extends in a vertical direction. When the detector is located in the sagittal focal plane of the optical element, the linear beam emitted by the transmitting module extends in a horizontal direction. When the optical element is free of astigmatism, the linear beam emitted by the transmitting module can extend in any direction. For example, the linear beam emitted by the transmitting module extends in a horizontal or vertical direction.

[0062] In a third aspect, an embodiment of the present application provides a radar or a radar system, which includes the receiving module shown in the above-mentioned first aspect or any possible implementation manner of the above-mentioned first aspect, or includes the detection device shown in the above-mentioned second aspect.

[0063] In a fourth aspect, an embodiment of the present application provides a terminal device, which includes the receiving module shown in the above-mentioned first aspect or any possible implementation method of the above-mentioned first aspect, or includes the detection device shown in the above-mentioned second aspect, or includes the radar or radar system shown in the above-mentioned third aspect.

[0064] In the fifth aspect, an embodiment of the present application provides a vehicle end, which includes the receiving module shown in the first aspect or any possible implementation of the first aspect, or includes the detection device shown in the second aspect, or includes the radar or radar system shown in the third aspect, or includes the terminal device shown in the fourth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The following is a brief introduction to the drawings required for describing the embodiments.

[0066] FIG1 is a schematic diagram of an application scenario of a detection device provided in an embodiment of the present application;

[0067] FIG2 is a schematic structural diagram of a detection device provided in an embodiment of the present application;

[0068] FIG3 is a schematic diagram of a line-scanning and line-collecting scanning method provided in an embodiment of the present application;

[0069] FIG4 is a schematic diagram of a coaxial architecture provided in an embodiment of the present application;

[0070] FIG5 is a schematic diagram of an off-axis architecture provided in an embodiment of the present application;

[0071] FIG6A is a schematic diagram of a meridian plane and a sagittal plane provided in an embodiment of the present application;

[0072] FIG6B is a schematic diagram of astigmatism provided in an embodiment of the present application;

[0073] FIG6C is a schematic diagram of an imaging law of astigmatism provided in an embodiment of the present application;

[0074] FIG6D is a schematic diagram of a field curvature provided in an embodiment of the present application;

[0075] FIG7 is a schematic diagram of a receiving module provided in an embodiment of the present application;

[0076] FIG8 is a schematic diagram of phase difference interference provided by an embodiment of the present application;

[0077] FIG9 is a schematic diagram of a detector configuration provided in an embodiment of the present application;

[0078] FIG10 is a schematic diagram of another detector configuration provided in an embodiment of the present application;

[0079] FIG11A is a schematic diagram of a top view of a receiving module provided in an embodiment of the present application;

[0080] FIG11B is a schematic diagram of a target light spot provided in an embodiment of the present application;

[0081] FIG11C is a schematic diagram of another target light spot provided in an embodiment of the present application;

[0082] FIG12 is a schematic diagram of a side view of a micro-cylindrical lens array and detector package provided in an embodiment of the present application;

[0083] FIG13 is a schematic diagram of another detector configuration provided in an embodiment of the present application;

[0084] FIG14 is a schematic diagram of another detector configuration provided in an embodiment of the present application;

[0085] FIG15 is a schematic diagram of a top view of another receiving module provided in an embodiment of the present application;

[0086] FIG16 is a schematic diagram of a detector configuration provided in an embodiment of the present application;

[0087] FIG17 is a schematic diagram of another detector configuration provided in an embodiment of the present application. DETAILED DESCRIPTION

[0088] In order to make the purpose, technical solutions and advantages of this application clearer, the embodiments of this application will be described below in conjunction with the drawings in the embodiments of this application.

[0089] The terms "first" and "second" in the specification, claims, and drawings of this application are used to distinguish different objects, not to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to the process, method, product, or device.

[0090] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It will be understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0091] It should be understood that in the present application, "at least one (item)" refers to one or more, "more than one" refers to two or more, "at least two (items)" refers to two or three and more than three, and "and / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0092] The following is an explanation of some of the terms used in this application. It should be noted that these explanations are for the purpose of facilitating understanding by those skilled in the art and are not intended to limit the scope of protection claimed in this application.

[0093] (1) Pixels.

[0094] In this article, pixel refers to the basic unit of image (including point cloud and image), and is also used to indicate a sample. In the field of computer vision, the information of a pixel is usually obtained by the output of one or more photoelectric conversion units, so the pixel is also used to represent the photoelectric conversion unit or photoelectric conversion unit group in the light receiver. In this field, pixels are commonly used to refer to one or more photoelectric conversion units (also called detection units, or simply cells). Furthermore, in the case of including multiple units, the multiple units within the pixel can be arranged in an array. For example, in an array detector, a pixel includes A rows and B columns of detection units, A is an integer and A≥1, and B is a positive number and B≥1.

[0095] (2)Pixel configuration.

[0096] The direction defined by a row of detection units can be referred to as the horizontal direction of the detector, and the direction defined by a column of detection units can be referred to as the vertical direction of the detector. In this application, a pixel is configured such that A rows and B columns of detection units are combined to form a pixel. For example, 3 rows and 12 columns of detection units form a pixel, or 6 rows and 6 columns of detection units form a pixel.

[0097] (3) Pixel shape.

[0098] The shape of a pixel can be represented by pixel length and pixel width, where pixel length represents the length of the pixel in the horizontal direction and pixel width represents the length of the pixel in the vertical direction. It should be noted that the following description takes the case where the detection units in the detector are of the same type and the detection units are evenly distributed in the detector as an example to introduce the present application. Therefore, the shape of the pixel depends on the configuration of the pixel. For example, for a pixel composed of A rows and B columns of detection units, the shape is also approximately a rectangle with a length of B and a width of A. There are some scenarios in which the detector includes different types of detection units, and the detection units are unevenly distributed in the detector. Combined with the description below and common sense in the field, this scenario still falls within the scope of protection of the present application.

[0099] (4) Detection area (also known as field of view), which represents the maximum range that can be observed. The detection area includes the horizontal detection area and the vertical detection area, and is usually expressed in angles. For example, the detection area can be represented in the format of A×B, where A represents the horizontal detection area and B represents the vertical detection area. Specifically, the detection area is 120°×60°. The detection area can be divided into the region of interest (ROI) and the non-ROI area. The ROI area is generally located at the center of the detection area (also known as the central field of view), while the non-ROI area is located at the edge of the detection area (also known as the edge field of view).

[0100] (5) ROI refers to the area in the detection area that needs to be processed or paid attention to, which is represented by a box, circle, ellipse, or irregular polygon. The region of interest generally includes the detection target.

[0101] (6) Light spot refers to the bright spot formed by a light beam, and also refers to the energy density (or intensity, power) distribution of the light beam. In the embodiments of the present application, the light spot can be regarded as the projection of the light beam on a certain surface.

[0102] (7) Point cloud, i.e., an aggregation or collection of points, where points (also called target points or data points) are generally used to indicate characteristics of an object. For example, a point indicates one or more of the following: position (e.g., one-dimensional, two-dimensional, or three-dimensional coordinate position), distance, angle, reflection intensity, color information, etc.

[0103] The above explanations of terms may be applied hereinafter.

[0104] The detection device uses signals as the detection medium. By transmitting signals to the detection area (i.e., the object space) and receiving the signal echo, it can detect the detection area, for example, to measure distance, speed, or azimuth. The detection device is provided with a transmitting module and a receiving module. The transmitting module is used to transmit signals, and the receiving module is used to receive signals. The signals here include light, such as lasers. When using light for detection, an optical system is provided in the detection device to process the light beam. The processing here includes one or more of splitting, filtering, converging, diverging, refraction, filtering, reflection, or scanning.

[0105] With the development of intelligence, the requirements of equipment for the detection accuracy of detection devices are getting higher and higher. Some solutions achieve high-density scanning of ROI through two-dimensional non-uniform scanning, thereby increasing the point cloud density of ROI and achieving high-resolution detection of ROI. However, the two-dimensional non-uniform scanning method has a complex structure, high cost, low reliability, and will also lead to limited aperture of the scanning mirror, thereby affecting the distance measurement performance of the detection device. Other solutions use DOE cascade to form high-density dot matrix illumination of ROI, thereby achieving high-resolution detection of ROI. However, the existing DOE process is immature, resulting in high cost of DOE, low temperature reliability, and diffraction efficiency far less than the transmittance of refractive optical elements, which affects the stability and distance measurement performance of the detection device. It can be seen that two-dimensional non-uniform scanning or DOE cascade is not conducive to the low-cost design of high-resolution lidar.

[0106] Therefore, the present application provides a receiving module, radar, terminal and vehicle end, which relate to the field of laser radar technology and can achieve high-resolution reception of laser radar and realize low-cost design of high-resolution laser radar.

[0107] The following first introduces an application scenario of the detection device provided by the present application. FIG1 exemplarily shows a schematic diagram of an application scenario of a detection device. In this example, the detection device 10 is installed on a vehicle, so it is also called a vehicle-mounted detection device. In addition, the detection device 10 also includes a ship-mounted detection device installed on a ship, and an airborne detection device installed on a machine, etc. In a possible example, as shown in FIG1 , the detection device 10 can send a detection signal, which is reflected after being irradiated by an object in front of the vehicle, and the reflected echo signal can be received by the detection device 10, and then the detection device 10 detects the obstacle information in front of the vehicle based on the echo signal, such as the size, speed and distance of the obstacle, so as to use the obstacle information to realize the driving function of the vehicle, including but not limited to automatic assumption or assisted driving.

[0108] In conjunction with Figure 2, the detection device 10 is introduced in detail. As shown in Figure 2, the detection device 10 includes a transmitting module 100, a receiving module 200 and a processing unit 300. The transmitting module 100 includes an excitation source (or called a laser driver), a laser 101, and an emitting optical system 102. The excitation source drives the laser 101 to emit a detection signal, such as a laser beam (or laser pulse), and the laser beam (or laser pulse) is emitted outward through the transmitting optical system 102. The receiving module 200 includes a receiving optical system 202 and a detector 201. After the detection signal emitted from the detection device 10 encounters a target object, it interacts with the target object to form a reflected / scattered echo signal. The echo signal is collected by the receiving optical system 202 and received by the detector 201, which converts the optical signal into an electrical signal. The electrical signal is then processed by the analog front end and passed to the processing unit 300. The processing unit 300 processes the received signals to obtain information such as the distance, speed, and azimuth of the target object. Furthermore, it can obtain information such as the target's surface morphology and physical properties to establish an object model. The detector 201 is typically a photodetector that converts the received light signal into an electrical signal. This electrical signal is typically an analog signal. The processing unit 300 is typically used to process digital signals, such as a digital signal processor (DSP). Therefore, the analog electrical signal is converted into a digital signal via an analog-to-digital converter (ADC) and provided to the processing unit 300. Furthermore, the electrical signal can be amplified, and the amplified electrical signal is converted into a digital signal via an ADC and provided to the processing unit 300. The processing unit 300 includes a signal processing circuit for processing the digital signal to obtain information such as the distance, speed, and azimuth of the target object, and further establish an object model. The detection device 10 also includes a control circuit, such as a control unit for controlling the excitation source and a control unit for controlling the scan drive circuit 402. These two control units can be integrated or provided independently. Furthermore, the signal processing circuit and the control circuit can be integrated or provided independently.

[0109] In addition, in one implementation, the emission module 100 may also include a laser modulator and a beam controller. The laser beam emitted by the laser 101 passes through the beam controller. Under the control of the laser modulator, the beam controller controls the direction and number of lines of the emitted laser beam. The laser beam emitted from the beam controller passes through the emission optical system 102 and is emitted outward.

[0110] In one implementation, the laser 101 may include one or more of the following light sources: vertical cavity surface emitting laser (VCSEL), photonic crystal surface emitting semiconductor lasers (PCSEL), edge emitting laser (EEL), laser diode (LD), distributed feedback laser diode (DFB-LD), grating coupled sampling reflection laser diode (GCSR-LD), or micro opto electro mechanical system laser diode (MOEMS-LD), etc.

[0111] In one implementation, the detector 201 may include, but is not limited to, a single-photon avalanche diode (SPAD), a silicon photomultiplier (SiPM), a multi-pixel photon counter (MPPC), a semiconductor avalanche photodiode (APD), or a "positive-intrinsic-negative" (PIN) diode (or a P-type semiconductor-impurity-N-type semiconductor diode), etc. In the case where the detector includes a plurality of detection units, the plurality of detection units may be arranged in an array to form an array detector, for example, the receiving module includes a SPAD array detector. The detector 201 may also be an image sensor, including one or more of the following photosensitive elements: complementary metal oxide semiconductor (CMOS), charge-coupled device (CCD), Live MOS, etc. For example, the image sensor includes a CMOS image sensor (CIS), which is used to convert optical images into electronic signals. In some scenarios, the detector and image sensor can be collectively referred to as a light receiving chip.

[0112] In one implementation, the transmitting optical system 102 and the receiving optical system 202 refer to systems composed of optical elements, including but not limited to: lenses, filters, polarizers, mirrors, beam splitters, prisms, windows, and scatterers.

[0113] In addition, the detection device 10 may also include a scanning unit 400. Under the action of the scanning unit 400, the detection signal emitted by the transmitting module 100 is scanned on the plane to generate real-time planar image information. The scanning unit 400 mainly includes a scanning mechanism 401 and a scanning drive circuit 402. The scanning drive circuit 402 is used to drive the operation of the scanning mechanism 401. Under the action of the scanning mechanism 401, the detection signal is transformed from a "line" to a "plane", or from a "point" to a "line" and then to a "plane".

[0114] Optionally, scanning mechanism 401 may include one or more of a one-dimensional oscillating mirror, a one-dimensional polygon mirror, a micro-electro-mechanical system (MEMS) galvanometer, or a metal galvanometer. In some embodiments, scanning mechanism 401 may include one or more reflective surfaces, which may be mounted in the form of patches on the main body of the scanning module. Alternatively, the reflective surfaces of scanning mechanism 401 and the main body of scanning mechanism 401 may be integrally formed. Optionally, scanning mechanism 401 may employ one-dimensional scanning.

[0115] In one possible embodiment, the transmitting module 100 and the receiving module 200 can scan the object using a line scanning and line receiving scanning method (also known as a line beam one-dimensional scanning architecture). For example, the detection signal emitted by the laser 101 is transmitted through the transmitting optical system 102 and displayed as a line spot on the YOX plane. After the line spot is adjusted by the scanning unit 400, it will scan a linear area corresponding to a vertical field of view angle FOV1 on the object each time (i.e., the horizontal line filling area on the object shown in Figure 2). In addition, the control circuit can control the laser 101 to repeatedly emit multiple detection signals in the form of pulsed lasers to detect the same linear area on the object. The number of detection signals can be set to a value between 10-500 for example. After scanning a linear area using multiple detection signals, the scanning unit 400 will control the multiple detection signals subsequently emitted by the transmitting optical system 102 to move to the next linear area along the positive direction of the illustrated X-axis (also known as the scanning direction of the detection signal) until the area corresponding to the entire horizontal field of view angle FOV2 is scanned, and it is determined that the detection area has been traversed. Correspondingly, the line beam emitted by the transmitting optical system 102 remains a line beam after being reflected by the object. This line beam is transmitted back to the receiving optical system 202 via the scanning unit 400. In the receiving optical system 202, it is transmitted and focused to the detection unit of the detector 201. The detector 201 converts the signal received by the detection unit into an electrical signal and transmits it to the processing unit 300. The processing unit 300 then generates point cloud data corresponding to each linear area and combines the point cloud data of each linear area to generate a frame of image. It should be noted that the Z axis is parallel to the optical axis of the detection device 10.

[0116] It should be understood that the light beam adjusted by the scanning unit 400 shown in FIG2 is a line beam parallel to the Y-axis, which is only a possible design. The embodiment of the present application does not specifically limit the form of the light beam. For example, in other designs, the line beam adjusted by the scanning unit 400 may also be parallel to the X-axis, and is used to scan a linear area corresponding to a horizontal field of view FOV2 on the object at a time, and moves along the positive or negative direction of the Y-axis in the figure until the area corresponding to the entire vertical field of view FOV1 is scanned. Alternatively, in some other designs, the line beam adjusted by the scanning unit 400 may also be an inclined line beam that forms a certain angle with both the X-axis and the Y-axis, and may move along the positive or negative direction of the X-axis in the figure, the positive or negative direction of the Y-axis, or other directions on the XOY plane until the area corresponding to the entire vertical field of view FOV1 and the entire horizontal field of view FOV2 is scanned. Alternatively, in some designs, some optical lenses can be set at special positions of the emitting optical system 102, so that the pulsed laser emitted by the laser 101 is converted into a dislocated beam or other special-shaped beam through the action of these optical lenses to adapt to more detection scenarios.

[0117] Refer to Figure 3, which is a schematic diagram of a line scanning and line collection scanning method provided by the present application. The surface of the object can be divided into N areas (the oblique line / horizontal line filled areas on the object shown in Figure 3 (a)), where N is an integer greater than or equal to 1. The detection signal scans the N areas in sequence. For example, the scanning order of the detection signal is area 1, area 2, ..., area N-1, area N (the serial numbers of the areas are represented by numbers / or letters in the figure). Optionally, the number of times the detection signal scans an area can be set. For example, the detection signal can be set to scan an area 300 times, and then scan the next area. Correspondingly, when the detection signal scans any area once, the echo signal will form a target light spot at the same position of the detector 201. For example, the target light spots will all be located at the position shown in Figure 3 (b). The detector 201 uses the detection unit as the minimum receiving unit of the target light spot, converts the target light spot into an electrical signal, and uses it for subsequent processing, such as sending the electrical signal to the processing unit 300. Exemplarily, a plurality of detection units are arranged in an array to form a pixel. For example, the detection units in the pixel shown in (b) of FIG3 are arranged in a 3×3 form. It should be noted that the arrangement of the detection units in the pixel will be given in more examples in conjunction with specific implementation methods below, and the 3×3 arrangement should not be used as a limitation of this application. The pixels covered by the target light spot in FIG3 can also be arranged in an 8×2 form, that is, two pixels in the X direction and 8 pixels in the Y direction. The target light spot in FIG3 covers two columns of pixels. In a specific implementation, the target light spot may cover one column of pixels or multiple columns of pixels, and this application does not limit this. It should be noted that the shape of the target light spot depends on the shape of the detection signal and one or more items in the receiving optical system 202, which will be specifically described below and will not be described in detail here.

[0118] It should be understood that the detection signal shown in FIG3 extends along the Y-axis (the detection signal is parallel to the Y-axis), which is only one possible design. In a specific implementation, the detection signal can also extend along the X-axis, or the extension direction of the detection signal forms a certain angle with the X-axis / Y-axis, which is not limited in this application.

[0119] It should be noted that the detection device 10 may be a laser radar. The application does not specifically limit the type of laser radar, which may be a mechanical laser radar, a liquid laser radar, a pure solid-state laser radar, or a hybrid solid-state laser radar (also known as a semi-solid-state laser radar).

[0120] In the case where the detection device 10 is a laser radar, the detection signal can also be called a laser beam (or simply a beam). When the detection device 10 scans an object using a line-scanning and line-collecting scanning method, the detection signal can also be called a line beam. According to the shape of the laser, the laser can be divided into a point laser and a line laser. The point laser requires that the emitted light beam be a collimated light beam, so that the light spot formed at a long distance is a point, thereby defining the collimation direction of the emitted light beam. The line beam requires that the emitted light beam be a collimated light beam in the first direction and a divergent light beam in the second direction, so that the light spot formed at a long distance is a line. The first direction can also be called the collimating direction, and the second direction can be called the diverging direction, wherein the diverging direction is also equivalent to the direction in which the line beam extends, or the direction in which the line beam is parallel. In conjunction with the coordinate system in Figure 2 or Figure 3 above, the vertical direction shown below can be understood as the Y direction, and the parallel direction can be understood as the X direction.

[0121] In one possible design, the transmitting module 100 and the receiving module 200 in the detection device 10 can be coaxial or off-axis. A coaxial design refers to an optical path architecture in which the main optical axes of the transmitting module 100 and the receiving module 200 coincide, while an off-axis design refers to an optical path architecture in which the main optical axes of the transmitting module 100 and the receiving module 200 do not coincide.

[0122] Referring to Figure 4, Figure 4 is a schematic diagram of a coaxial architecture exemplarily provided in the present application. The coaxial architecture shown in Figure 4 realizes the coaxiality of the detection signal and the echo signal through the scanning unit 400. The detection signal is reflected to the object space through the scanning unit 400, and the echo signal is received by the receiving module 200 without passing through the scanning unit 400 (for example, passing through both sides of the scanning unit 400). In conjunction with Figure 2 above, the scanning unit 400 includes a scanning drive circuit 402 and a scanning mechanism 401. Among them, the scanning mechanism 401 may include one or more of a one-dimensional swing mirror, a one-dimensional rotating mirror (polygon), a micro-electro-mechanical system (MEMS) galvanometer, or a metal galvanometer. In some embodiments, the scanning mechanism 401 may include one or more reflecting surfaces, and the reflecting surface may be mounted on the main body of the scanning module in the form of a patch, or the reflecting surface of the scanning mechanism 401 and the main body of the scanning mechanism 401 may also be integrated. Optionally, the scanning mode of the scanning mechanism 401 may be one-dimensional scanning.

[0123] See Figure 5, which is a schematic diagram of an off-axis architecture exemplified in this application. The primary optical axes of the transmitting module 100 and the receiving module 200 shown in Figure 5 do not coincide, and the optical paths of the detection signal and the echo signal are also different. In an off-axis architecture, the transmitting and receiving optical paths are effectively isolated, thereby improving the detection performance of the detection device 10.

[0124] It is understandable that, whether it is an off-axis design or an on-axis design, the optical components will have a huge impact on the final imaging quality. For example, in an ideal imaging system, the following three conditions are met:

[0125] 1. All light rays from the same point on the object will converge to the same point on the image.

[0126] 2. If the plane formed by all points on the object (object plane) is perpendicular to the optical axis, then the plane formed by all points on the image (image plane) is also perpendicular to the optical axis (the image field is flat).

[0127] 3. The ratio of image height to object height is constant for all points on the image and object planes (given the object and image distances, there is only one magnification).

[0128] However, in actual imaging systems, ideal imaging systems are often unattainable or extremely expensive, hindering product commercialization. Therefore, phase aberration often exists in actual imaging systems. Simply put, the difference between actual and ideal imaging can be called phase aberration.

[0129] In one possible classification method, the phase difference can be classified according to attributes such as color (or wavelength) and position.

[0130] For example, according to the relationship between phase difference and color (wavelength), it can be divided into monochromatic phase difference and chromatic aberration.

[0131] For example, based on the relationship between the phase difference and the position of the object point, the monochromatic phase difference can be divided into on-axis point phase difference and off-axis point phase difference, where the "axis" refers to the main optical axis of the optical system.

[0132] Furthermore, the off-axis point aberration can be divided into astigmatism, field curvature, coma and distortion according to the cause of the aberration.

[0133] Among them, astigmatism is due to the different focusing effects when the object point light beams in the meridional focal plane and the sagittal focal plane are focused by the optical element. As a result, all the light beams on the object point cannot be focused on the same point, resulting in unclear imaging. Please refer to Figure 6A. The light rays emitted from object point A are all focused on image point A1 through the optical element. As shown in Figure 6A, the section passing through object point A and the principal optical axis is called the meridional plane, and the section passing through the principal light ray and perpendicular to the meridional plane is called the sagittal plane. The light beam in the above-mentioned meridional plane is called the meridional light beam, and the image formed by the meridional light beam is called the meridional image point. The image plane where the meridional image point is located is called the meridional image plane, also known as the meridional focal plane. Similarly, the light beam in the sagittal plane is called the sagittal light beam, and the image formed by the sagittal light beam is called the sagittal image point. The image plane where the sagittal image point is located is called the sagittal image plane, also known as the sagittal focal plane.

[0134] For ease of description, the following assumptions can be made. As shown in Figure 6B, the direction perpendicular to the principal ray in the meridional plane is called the Y direction, the direction perpendicular to the principal ray in the sagittal plane is called the X direction, and the direction parallel to the principal optical axis is called the Z direction. The effect of astigmatism / field curvature on the beam diffusion can be divided into diffusion in the Y and X directions.

[0135] Please refer to Figure 6B, which is a schematic diagram of astigmatism provided in an embodiment of the present application. As shown in Figure 6B, the meridional image point and the sagittal image point do not coincide (or, the meridional focal plane and the sagittal focal plane do not coincide). For example, the meridional beam focuses earlier than the sagittal beam, and the meridional image point is closer to the optical element.

[0136] In one possible implementation, when there is astigmatism in the optical element, the spot shape corresponding to the object point will change as the image plane moves. Specifically, there are five cases:

[0137] For ease of description, the following rules are made: if the image plane is located before XX (meridional image point / sagittal image point), it is understood that the distance between the image plane and the optical element is smaller than the distance between the image plane and XX. If the image plane is located after XX, it is understood that the distance between the image plane and the optical element is larger than the distance between the image plane and XX.

[0138] Case 1: The image plane is located in front of the meridional image point. In this case, the light spot corresponding to the object point has a greater diffusion degree in the sagittal plane than in the meridional plane, so the light spot is elliptical. Specifically, the length of the elliptical light spot in the X direction is greater than the length in the Y direction.

[0139] Case 2: The image plane is the meridional focal plane. In this case, the meridional beam is focused, while the sagittal beam is diverging. Therefore, the light spot corresponding to the object point only spreads within the sagittal plane, forming a straight line (a line spot). The length of the line is related to the degree of astigmatism. Specifically, this line spot extends in the X direction.

[0140] Case 3: The image plane is located behind the meridional image point and before the sagittal image point. In this case, both the meridional and sagittal beams are diverging, and the degree of divergence changes as the image plane moves. Therefore, the light spot corresponding to the object point will exhibit different shapes. For example, as the image plane moves from the meridional image point to the sagittal image point, the light spot corresponding to the object point will successively appear as an ellipse (with a greater length in the X direction than in the Y direction), a circle, and then an ellipse (with a greater length in the Y direction than in the X direction).

[0141] Case 4: The image plane is the sagittal focal plane. In this case, the sagittal beam is focused, while the meridional beam is diverging. Therefore, the light spot corresponding to the object point only spreads within the meridional plane, forming a straight line (a line spot). The length of the line is related to the degree of astigmatism. Specifically, the line spot extends in the Y direction.

[0142] Case 5: The image plane is behind the sagittal image point. In this case, the light spot corresponding to the object point diffuses more in the meridional plane than in the sagittal plane, resulting in an elliptical light spot. Specifically, the length of the elliptical light spot in the Y direction is greater than its length in the X direction.

[0143] In another possible implementation, the degree of diffusion of the sub-beams caused by astigmatism gradually increases as the distance between the sub-beams and the main optical axis increases, or the degree of diffusion of the sub-beams caused by astigmatism is proportional to the square of the field of view angle.

[0144] It's understood that a line beam reflected by an object includes multiple sub-beams reflected from the object point. Ideally, the sub-beams are imaged as a single point on the detector. However, due to phase aberration, these sub-beams appear as spots on the detector. The distance between a sub-beam and the principal optical axis can be equivalent to the distance between the object point / image point / spot and the principal optical axis.

[0145] For example, taking the above-mentioned case 1 as an example, the image plane is located in front of the meridian image point, and the light spot corresponding to the object point is elliptical. Referring to Figure 6C, light spot A is located near the principal optical axis, and light spots B and C are equidistant from the principal optical axis. Light spots A, B, and C are all elliptical, with lengths in the Y direction of d1, d2, and d3, respectively, where d2 = d3 > d1. It can be understood that the degree of diffusion of the light spots in the Y direction is different, that is, as the distance between the light spots and the principal optical axis increases, the degree of diffusion of the light spots in the Y direction increases. In the X direction, the length of light spot A is d4, and the lengths of light spots B and C are d5. d5 > d4, that is, the degree of diffusion of the light spots in the X direction increases as the distance between the light spots and the principal optical axis increases, and different light spots with the same distance from the principal optical axis have the same degree of diffusion in the X direction.

[0146] It should be noted that in the astigmatism shown in FIG6B , the meridional beam is focused before the sagittal beam. In some implementations, the sagittal beam may also be focused before the meridional beam. Both scenarios are applicable to the solution provided in this application, and the scenario shown in FIG6B will be used as an example for description below.

[0147] It is understandable that if an optical element has astigmatism, it will also be accompanied by field curvature. Conversely, if an optical element has field curvature, it will not necessarily have astigmatism.

[0148] Please refer to Figure 6D, which is a schematic diagram of a field curvature provided in an embodiment of the present application. As shown in Figure 6D, the focal plane of the optical element is a curved surface. As the distance between the object point and the main optical axis increases, the meridional beam and the sagittal beam cannot be focused on the image plane, and the degree of divergence is the same. Therefore, the light spot corresponding to the object point near the main optical axis can be focused into a point, and the light spot corresponding to the object point far away from the main optical axis is a circle, and as the distance between the object point and the main optical axis increases, the area of ​​the light spot corresponding to the object point continues to increase. As shown in Figure 6D, the distance d1 between spot A and the main optical axis is smaller than the distance d2 between spot B and the main optical axis, then the area of ​​spot A is smaller than spot B. The distance d2 between spot B and the main optical axis is equal to the distance d3 between spot C and the main optical axis, then the area of ​​spot B is equal to spot C. Spot D is located on the main optical axis, then spot D is a point spot.

[0149] It should be noted that in the field curvature diagram shown in FIG6D , the focal plane is curved toward the optical element. In one possible scenario, field curvature may also cause the focal plane to bend in the opposite direction of the optical element (please refer to FIG6D for understanding, which is not shown in the figure). In this case, the effect of field curvature on the diffusion of the light spot can be seen in FIG6D , and will not be further described here.

[0150] Please refer to Figure 7, which is a schematic diagram of a receiving module exemplified in the present application. As shown in Figure 7, the lens module is composed of optical elements and a detector 201. The optical elements may include but are not limited to: a convex lens and a concave lens, etc., wherein the convex lens may be a biconvex lens, a plano-convex lens and a concave-convex lens, etc. The concave lens may be a biconcave lens, a plano-concave lens, a convex-concave lens, etc. Specifically, as shown in Figure 7, the arrangement of the optical elements from left to right is a glass cover, a plano-convex lens, a biconcave lens and two convex-concave lenses. The light beam passing through the optical element is received by the detector 201, and is converted into an electrical signal by the detector 201 and sent to the processing unit for generating an image.

[0151] Optionally, when the optical element cooperates with the detector 201 to receive the light beam and convert the light signal into an electrical signal, the optical element shown in FIG7 can be referred to as a receiving optical system, such as the receiving optical system 202 shown in FIG2 .

[0152] Optionally, in the coaxial architecture shown in FIG4 above, the optical element described in FIG7 can also be used to cooperate with the laser and the laser's excitation source to emit a detection signal. In this case, the optical element shown in FIG7 can be referred to as an emitting optical system, such as the emitting optical system 102 shown in FIG2 above.

[0153] It is understandable that optical elements acting as transmitting or receiving optical systems will have phase differences. For example, the optical element shown in FIG7 has astigmatism and / or field curvature. To this end, this application exemplarily provides three receiving module design solutions, which utilize the astigmatism and / or field curvature of optical elements in combination with a specified pixel configuration to achieve high-resolution detection by the detection device, thereby enabling a low-cost and compact design of the detection device.

[0154] Before introducing the design scheme of the receiving module, the following explanation is made. The receiving module provided in this application can achieve high-resolution detection under high dynamic range based on the one-dimensional scanning architecture of the linear beam (as shown in Figure 2 above). Taking Figure 2 above as an example, in the subsequent introduction, the design scheme of the receiving module 200 will be combined to specifically introduce the extension direction of the linear beam emitted by the detection device 10. Other implementations of the transmitting module 100 and the scanning unit 400 in the detection device 10 are not specifically limited.

[0155] In a possible implementation, the receiving module includes an optical element and a detector, wherein the receiving module is, for example, the receiving module 200 shown in FIG2 , and the optical element and the detector are a receiving optical system 202 and a detector 201 , respectively.

[0156] The detector is located at the target focal plane of the optical element. It is understood that if the optical element has astigmatism, the meridional and sagittal focal planes of the optical element do not coincide, and the target focal plane can be either the meridional or sagittal focal plane. If the optical element does not have astigmatism, the meridional and sagittal focal planes coincide. In this case, the target focal plane refers to a fixed focal plane, also known as the optimal focal plane.

[0157] The receiving module is used to receive a first light beam, which is a linear light beam extending along a first direction. Taking Figure 3 above as an example, the first direction is, for example, the Y direction (also known as the vertical direction) shown in Figure 3. Optionally, the first direction can also be the X direction (also known as the horizontal direction) shown in Figure 3, which is not limited in this application. In one possible implementation, the extension direction of the light beam is aligned with the target focal plane (meridional focal plane / sagittal focal plane) where the detector is located. The specific implementation can be seen in the description below.

[0158] Optionally, the optical element is configured to astigmatize the first light beam in a second direction. Taking Case 2 (Case 4) shown in Figure 6B above as an example, the image plane is the meridional focal plane (sagittal focal plane), and the light spot corresponding to the object point diffuses only within the sagittal plane (meridional plane), forming a straight line extending along the X direction (Y direction). This diffusion within the sagittal or meridional plane is referred to as astigmatism of the light beam by the optical element in the X direction (Y direction).

[0159] The optical element is used to perform field curvature on the first light beam. Taking FIG6D as an example, the field curvature will cause the light spots at different positions to exhibit different degrees of diffusion. For details, please refer to the description of FIG6D above, which will not be repeated here.

[0160] The extension direction of the first light beam (the first direction) is perpendicular to the direction of astigmatism (the second direction). For example, in Case 2 of Figure 6B , if the astigmatism causes the light spot to spread along the X direction, the extension direction of the first light beam should be the Y direction. For example, in Case 4 of Figure 6B , if the astigmatism causes the light spot to spread along the Y direction, the extension direction of the first light beam should be the X direction. Furthermore, the direction of astigmatism can also be at a specified angle to the X / Y axis; the extension direction of the first light beam should still be perpendicular to the direction of astigmatism.

[0161] The detector includes multiple monitoring areas. It should be noted that the detector including multiple monitoring areas can be a conceptual division. In the specific implementation process, the area on the detector for receiving the light beam can be divided into multiple areas (equivalent to the detector including multiple monitoring areas).

[0162] The pixel shapes of multiple monitoring areas are different. Different monitoring areas can be configured with different pixels to achieve different detection resolutions in different monitoring areas. For example, the area on the detector for receiving the light beam can be divided into a first monitoring area, a second monitoring area, and a third monitoring area. Among them, the configuration of pixels in the first monitoring area and the second monitoring area is 6×6, and the configuration of pixels in the second monitoring area is 3×12. For a more specific introduction, please refer to the subsequent related descriptions, which are not described in detail here. Optionally, the pixel shapes of multiple monitoring areas are different, and it can also be understood that there are at least two pixel configurations in multiple monitoring areas. For example, the detector includes 5 monitoring areas, and there are three pixel configurations in the 5 monitoring areas.

[0163] It is understandable that the detection device provided by the present application is based on a one-dimensional scanning architecture of a line beam, and the scanning direction (X direction) of the line beam is perpendicular to the extension direction of the line beam. The number of pixels corresponding to a line beam in the scanning direction is related to the width of the line beam, the sampling resolution, etc. Therefore, the number of pixels generated in the scanning direction when different monitoring areas receive the same line beam is equal. For example, the first monitoring area and the second monitoring area receive the first beam, and the number of pixels generated in the scanning direction is N columns, where N is a positive integer. For example, N = 1, 2, ..., 100, etc.

[0164] Next, by introducing optical elements and detectors respectively, three design schemes of receiving modules are shown. These three receiving modules can be applied to the detection device 10 shown in FIG. 2 .

[0165] Design solution 1: The receiving module includes an optical element and a detector, wherein the optical element has astigmatism and field curvature, and the detector includes multiple monitoring areas, and the pixel shapes in the multiple monitoring areas are different but the pixel areas are equal.

[0166] In one possible implementation, the first direction depends on the target focal plane.

[0167] For example, if the target focal plane is the meridional focal plane, the beam within the meridional plane of the target focal plane can be focused, while the beam within the sagittal plane is in a divergent state. The first direction should be parallel to the meridional plane and perpendicular to the sagittal plane. Taking Case 2 in Figure 6B as an example, if astigmatism causes the light spot to diverge within the sagittal plane, the first direction should be the Y direction, and the corresponding second direction should be the X direction.

[0168] For example, when the target focal plane is the sagittal focal plane, the light beam within the sagittal plane can be focused, while the light beam within the meridional plane is in a divergent state. The first direction should be parallel to the sagittal plane and perpendicular to the meridional plane. Taking Case 4 in Figure 6B as an example, if astigmatism causes the light spot to diverge within the meridional plane, the first direction is the X direction, and the corresponding second direction is the Y direction.

[0169] Figures 6B and 6C above only illustrate the diffusing effect of astigmatism on sub-beams. For a clearer illustration of the combined diffusing effect of astigmatism and field curvature on a linear beam, please refer to Figure 8. Figure 8 illustrates this using the example of a first direction being the Y direction, a second direction being the X direction, and a detector located in the meridional or sagittal focal plane of an optical element. The first beam can, for example, be a linear beam reflected from an object, extending along the Y direction. The light spot formed by the receiving module receiving the first beam should also extend along the Y direction, as shown in the "ideal light spot" of Figure 8. As shown by the light spot corresponding to "astigmatism" in Figure 8, due to the effect of astigmatism, the light spot formed by the receiving module receiving the first beam diffuses in the X direction. As the distance between the light spot and the principal optical axis increases, the diffusing effect of astigmatism in the X direction gradually increases. As shown by the light spot corresponding to "field curvature" in Figure 8, due to the effect of field curvature, the light spot formed by the receiving module receiving the first beam diffuses in both the X and Y directions. As the distance between the light spot and the principal optical axis increases, the diffusing effect of field curvature in both the X and Y directions gradually increases. As shown in the light spot corresponding to the "field curvature + astigmatism" scenario in Figure 8, due to the combined effects of astigmatism and field curvature, the sub-beam near the principal optical axis is only diffused by astigmatism in the X direction, resulting in a linear light spot extending along the X direction. As the distance between the sub-beam and the principal optical axis increases, the diffusing effect of astigmatism in the X direction increases, while the effect of field curvature in the X and Y directions increases, resulting in an elliptical light spot. As the distance between the sub-beam and the principal optical axis continues to increase, the diffusing effect of astigmatism in the X direction decreases, while the effect of field curvature in the X and Y directions increases, maintaining the elliptical shape of the light spot. It should be noted that the light spot shown in Figure 8 may be a sample of an actual light spot, used to better illustrate the diffusion effects corresponding to astigmatism, field curvature, or both. It should be understood that Figure 8 illustrates the diffusion effect experienced by the first light beam when the target focal plane is the meridional focal plane. For the diffusion effect experienced by the first light beam when the target focal plane is the sagittal focal plane, please refer to the relevant description in Figure 8.

[0170] As shown in Figure 8 for the "field curvature + astigmatism" light spot, the light spot near the principal optical axis has minimal spread in the Y and X directions. As the distance from the principal optical axis increases, the spread in the X and Y directions increases. To address this issue, multiple monitoring areas can be set up on the detector to receive light spots at different locations. Each monitoring area includes multiple pixels.

[0171] The detector includes a first monitoring area and a second monitoring area. As shown in FIG9 , the area for receiving light beams in the detector 201 includes a first monitoring area and a second monitoring area. The first monitoring area is used to receive light beams near the main optical axis, and the second monitoring area is used to receive light beams at other locations. The first monitoring area is, for example, the area covered by the horizontal stripes in FIG9 , and the second monitoring area is, for example, the area covered by the vertical stripes in FIG9 . The light beam near the main optical axis may refer to a light beam whose diffusion degree in the first direction is less than a preset threshold, that is, a light beam that can be well focused in the first direction. This will be described in detail below and will not be described in detail here.

[0172] The location design of the first monitoring area and the second monitoring area can be as follows:

[0173] In one possible design, the first monitoring area and the second monitoring area are connected but do not overlap. For example, the first monitoring area and the second monitoring area do not include the same detection unit, that is, a detection unit only belongs to the first monitoring area or the second monitoring area.

[0174] In another possible design, the first and second monitoring areas are arranged parallel to the direction of extension of the first light beam. Specifically, the first and second monitoring areas are arranged parallel to the first direction. As shown in FIG9 , when the first light beam extends in the Y direction, the first and second monitoring areas are arranged parallel to the Y direction. Of course, when the first light beam extends in the X direction, the first and second monitoring areas are arranged parallel to the X direction.

[0175] In another possible design, the principal optical axis passes through the center of the first monitoring area. For example, when the detector 201 is coupled to the optical element, the focal point of the optical element is located at the center of the first monitoring area. For example, if the target focal plane is a meridional focal plane, the focal point within the meridional focal plane is located at the center of the first monitoring area. For another example, if the target focal plane is a sagittal focal plane, the focal point within the sagittal focal plane is located at the center of the first monitoring area.

[0176] The design of the pixels in the first monitoring area and the second monitoring area can be as follows:

[0177] A possible design scheme is that in the first direction, the length of the pixels in the first monitoring area is smaller than the length of the pixels in the second monitoring area. As shown in Figure 9, in the Y direction (first direction), the length of the pixels in the first monitoring area is 3, and the length of the pixels in the second monitoring area is 6. The smaller the length of the pixels in the first direction, the more pixels can be generated in the first direction within the same length, which can improve the imaging resolution. Therefore, the imaging resolution corresponding to the first monitoring area of ​​the detector 201 shown in Figure 9 will be higher than the imaging resolution corresponding to the second monitoring area. In addition, the present application does not limit the length of the pixels in the first monitoring area and the second monitoring area in the first direction. For example, in the first direction, the length of the pixels in the first monitoring area can also be 1, 2, 4, 5, 6 or 7, and the length of the pixels in the second monitoring area can also be 3, 4, 5, 6, 7 or 8, etc., as long as it is ensured that in the first direction, the length of the pixels in the first monitoring area is greater than the length of the pixels in the second monitoring area.

[0178] Another possible design scheme is that in the second direction, the length of the pixels in the first monitoring area is greater than the length of the pixels in the second monitoring area. As shown in Figure 9, in the X direction (second direction), the length of the pixels in the first monitoring area is 12, and the length of the pixels in the second monitoring area is 6. This application also does not limit the length of the pixels in the first monitoring area and the second monitoring area in the second direction. For example, in the second direction, the length of the pixels in the first monitoring area can also be 6, 8, 10, 14 or 16, and the length of the pixels in the second monitoring area can also be 4, 8, 10 or 12, etc., as long as it is ensured that in the second direction, the length of the pixels in the first monitoring area is less than the length of the pixels in the second monitoring area. By designing that the length of the pixels in the first monitoring area is greater than the length of the pixels in the second monitoring area in the second direction, it can be ensured that the dynamic range of imaging in the first monitoring area is not reduced.

[0179] Another possible design scheme is that the areas of the pixels in the first monitoring area and the second monitoring area are equal. By designing that the areas of the pixels in the first monitoring area and the second monitoring area are equal, the areas (numbers) of the light beams received by the pixels in different monitoring areas can be equal, thereby ensuring that the dynamic ranges of the corresponding imaging in different monitoring areas are the same, and thus facilitating subsequent processing of the imaging (for example, splicing, fusion, encoding, etc.). Taking Figure 9 above as an example, the configuration of the pixels in the first monitoring area can be 6×6, and the configuration of the pixels in the second monitoring area can be 3×12. For another example, the configuration of the pixels in the first monitoring area can be 4×4, and the configuration of the pixels in the second monitoring area can be 2×8. For another example, the configuration of the pixels in the first monitoring area can be 8×8, and the configuration of the pixels in the second monitoring area can be 4×16, etc.

[0180] In another possible design, the length c of the pixels in the second monitoring area in the first direction and the length d in the second direction satisfy the following relationship: d = M * c, where M is greater than or equal to 1 and less than 2. As shown in Figure 9, c = d = 6. By designing the pixels in the second monitoring area to satisfy this relationship, the second monitoring area can receive light beams affected by field curvature, thereby accurately imaging. Alternatively, if the optical element only includes field curvature, c = d can be designed.

[0181] It should be noted that FIG9 is merely an exemplary illustration of a design of the detector 201. The detector 201 may include more or fewer pixels, and each pixel may have a different configuration. For details, please refer to the design illustrated above. Therefore, FIG9 should not be construed as limiting the present application.

[0182] As can be seen from the detector 201 shown in Figure 9, the detector 201 includes a first monitoring area and a second monitoring area, and the first monitoring area and the second monitoring area occupy all detection units in the detector 201. Combined with Figure 6B above, it can be seen that under ideal imaging conditions, the light spot formed by the first light beam on the detector is a linear spot, and not all detection units on the detector are required. In addition, due to design errors in optical components, background noise may be introduced, interfering with the imaging results.

[0183] To this end, the present embodiment also provides another design for a detector 201. As shown in Figure 10, the detector 201 includes a first monitoring area, a second monitoring area, and a third monitoring area. The first and second monitoring areas are used to receive light beams passing through the optical element. For a detailed description, please refer to the first and second monitoring areas shown in Figure 9 and will not be repeated here.

[0184] The third monitoring area is covered by an obstruction (the area covered by the diagonal lines in Figure 10) to prevent the detection unit in the third monitoring area from receiving stray light beams, thereby interfering with the imaging of the first monitoring area and the second monitoring area. For example, the detection unit in the third monitoring area can be prevented from receiving stray light beams by means of silk screen printing, coating, electroplating, or dispensing. Regarding the configuration of the elements in the third monitoring area, the embodiment of the present application does not limit it. What is shown in Figure 10 is only exemplary, and the content shown in Figure 10 should not be used as a limitation of this application. For example, the configuration of the elements in the third monitoring area can be 6×6, 3×12, etc. Since the elements in the third monitoring area do not receive light beams, they may not be configured.

[0185] Furthermore, this application does not impose any limitation on the number of pixels in the second direction when the detector 201 receives a line beam. The detector 201 shown in FIG10 receives a line beam and generates four columns of pixels in the second direction. In a specific implementation, the detector 201 may also generate 10, 20, 50, or 90 columns of pixels in the second direction when it receives a line beam, and this application does not impose any limitation on this.

[0186] Design solution 2: The receiving module includes an optical element, a detector and a micro-cylindrical lens array, wherein the optical element has field curvature, the detector includes multiple monitoring areas, and the pixel shapes in the multiple monitoring areas are different but the pixel areas are equal.

[0187] It should be noted that in the second design, the phase difference of the optical element does not include astigmatism, that is, the meridional focal plane and the sagittal focal plane of the optical element coincide, so the plane where the detector is located can be called the optimal focal plane.

[0188] In one possible design, a micro-cylindrical lens array is disposed on the detector to diverge the light beam passing through the optical element in a second direction.

[0189] Please refer to Figure 11A, which is a schematic diagram of a top view of a receiving module provided in an embodiment of the present application. The first light beam received by the optical element extends along the Y direction (first direction), and the micro-column lens array is used to make the first light beam diverge in the X direction (second direction). It can be understood that although the first light beam extends along the Y direction, the first light beam also has a certain width in the X direction, such as 1 mm or 2 mm, etc., and the present application does not limit this. For example, the micro-column lens array can be controlled to diverge part of the light beam passing through the optical element, and the micro-column lens array can also be controlled to diverge all the light beams passing through the optical element.

[0190] It should be noted that the divergence effect of the micro-column lens array or the cylindrical lens hereinafter on the light beam can be to diverge the light beam in a certain direction (the second direction). For example, for a light beam that is ideally imaged as a point light spot, the micro-column lens array can diverge it into a line light spot. For a light beam that is ideally imaged as a line light spot, the micro-column lens array can diverge it into a surface light spot, or a line light spot with a longer length (depending on whether the divergence direction is the same as the extension direction of the line light spot). For example, please refer to Figures 11B and 11C. Among them, Figure 11B shows the case where the light beam received by the detector 201 does not pass through the micro-column lens array or the cylindrical lens, and the target light spot covers a column of pixels (line light spot) in the X direction. Figure 11C shows the case where the light beam received by the detector 201 passes through the micro-column lens array or the cylindrical lens, and the target light spot is diffused in the X direction, and the target light spot covers four columns of pixels (surface light spot) in the X direction.

[0191] Please refer to FIG. 12 , which is a schematic diagram of a side view of a micro-column lens array and detector package provided in an embodiment of the present application. FIG. 12 includes a micro-column lens array, an isolation layer, and a detector 201 .

[0192] In conjunction with Figure 11A, it can be seen that the micro-column lens array is used to allow the first light beam to diverge in the X direction. The isolation layer is used to isolate the divergent light generated by the micro-column lens array to prevent the divergent light generated by the micro-column lens from diverging in the Y direction, thereby interfering with other monitoring areas. It can be understood that the isolation layer is relatively small in size and will not affect the normal operation of the detection unit in the detector. For example, the isolation layer can be set in the gap between the two detection units so as not to affect the detection unit receiving the light beam. The material of the spacer layer can be silicon oxide, silicon nitride, metal oxide, metal nitride, etc., for example, one or more of silicon dioxide, silicon nitride, aluminum oxide, aluminum nitride, hafnium oxide, zirconium oxide, zinc oxide, titanium dioxide and the like. The detector 201 can include a first monitoring area and a second monitoring area. For a specific description, please refer to Figure 9 or Figure 10 above.

[0193] In one possible design, an isolation layer may be provided at the junction of the first monitoring area and the second monitoring area to prevent the light beam diffused by the microcylindrical lens array from being received by the second monitoring area, thereby affecting imaging of the second monitoring area.

[0194] In one possible design, the isolation layer is used to isolate the micro-cylindrical lens array and the detector by a certain distance, so that the light beam diverged by the micro-cylindrical lens array can be received by the detector.

[0195] In a possible design solution, the micro-cylindrical lens array is used to diffuse the light beam received by the first monitoring area in the second direction.

[0196] As shown in Figure 12, the micro-cylindrical lens array is placed above the first monitoring area and can diffuse the light beam received by the first monitoring area in the X direction (the second direction). This causes the light spot received by the first monitoring area to expand in the X direction, thereby ensuring the dynamic range of the corresponding imaging of the first monitoring area.

[0197] To further illustrate the position of the micro-cylindrical lens array within detector 201, please refer to Figure 13 . The first and second monitoring areas included in Figure 13 can be found in the description of Figure 9 above, and will not be repeated here. A micro-cylindrical lens array is also located above the first monitoring area. This micro-cylindrical lens array is used to diffuse the light beam received by the first monitoring area in the X direction. For details, please refer to the description of Figures 11A and 12 above.

[0198] In another possible design, a portion of the monitoring area of ​​detector 201 is covered by an obstruction to reduce the impact of stray light beams on the corresponding imaging of detector 201. Please refer to Figure 14. The first, second, and third monitoring areas included in Figure 14 can be referred to in the description of Figure 10 above and will not be repeated here. A micro-cylindrical lens array is also positioned above the first monitoring area. This micro-cylindrical lens array is used to diffuse the light beam received by the first monitoring area in the X direction. Please refer to the relevant description of Figures 11A, 11B, 11C, and 12 above.

[0199] In one possible implementation, in order to ensure that the light beam received by the first monitoring area is a light beam that has passed through the micro-column lens array, it is necessary to set a cover above the area in the first monitoring area where the micro-column lens array is not set (the area covered by the diagonal lines in Figure 13 or Figure 14) to prevent the light beam that has not passed through the micro-column lens array from being received by the first monitoring area. For an introduction to the cover, please refer to the description of Figure 10 above, which will not be repeated here. It should be noted that the area of ​​the first monitoring area blocked by the cover is only used to prevent the light beam that has passed through the optical element from being directly received by the first monitoring area. The area of ​​the first monitoring area blocked by the cover can still receive the light beam that has been diffused by the micro-column lens array.

[0200] In another possible implementation, the length of the micro-cylindrical lens array is equal to the length of the first monitoring area in a first direction, and is less than the length of the first monitoring area in a second direction. For example, in the first direction, the micro-cylindrical lens array overlaps with the first monitoring area, and in the second direction, the center of the micro-cylindrical lens array coincides with the center of the first monitoring area, or in the second direction, the micro-cylindrical lens array is located at the center of the first monitoring area, thereby ensuring that light passing through the micro-cylindrical lens array is evenly distributed throughout the first monitoring area.

[0201] Figure 11A shows a side view of the micro-cylindrical lens array and detector package, and Figure 12 shows a top view of the micro-cylindrical lens array and detector package. In another possible design, the micro-cylindrical lens array can be embossed on the detector's cover glass (CG). Another possible design is to integrate the micro-cylindrical lens array and detector using micro-nano processing.

[0202] Design solution three: The receiving module includes an optical element, a detector and a cylindrical lens, wherein the optical element has field curvature, the detector includes multiple monitoring areas, and the pixel shapes in the multiple monitoring areas are different but the pixel areas are equal.

[0203] It should be noted that in the second design, the phase difference of the optical element does not include astigmatism, that is, the meridional focal plane and the sagittal focal plane of the optical element coincide, so the plane where the detector is located can be called the optimal focal plane.

[0204] In a possible design solution, a cylindrical lens is disposed between the optical element and the detector, and is configured to diverge the light beam passing through the optical element in a second direction.

[0205] Please refer to Figure 15, which is a schematic diagram of a top view of another receiving module provided in an embodiment of the present application. The first light beam received by the optical element extends along the Y direction (first direction), and the cylindrical lens is used to make the first light beam diverge in the X direction (second direction). It is understandable that although the first light beam extends along the Y direction, the first light beam also has a certain width in the X direction, such as 1 mm or 2 mm, etc., and this application does not limit this. It should be noted that due to its large size, the cylindrical lens usually diverges all light beams passing through the optical element.

[0206] In a possible design, the cylindrical lens can be mounted together with the optical element, that is, the cylindrical lens is disposed in the receiving optical system 202 .

[0207] In another possible design, the cylindrical lens can be installed together with the detector, that is, the cylindrical lens is set in the detector 201.

[0208] The detector includes a fourth monitoring area and a fifth monitoring area. As shown in Figure 16, the area of ​​detector 201 used to receive light beams includes a fourth monitoring area and a fifth monitoring area. The fourth monitoring area is used to receive light beams near the main optical axis, while the fifth monitoring area is used to receive light beams at other locations. The fourth monitoring area is, for example, the area covered by the horizontal stripes in Figure 16, and the fifth monitoring area is, for example, the area covered by the vertical stripes in Figure 16.

[0209] The position design of the fourth monitoring area and the fifth monitoring area may refer to the position design of the first monitoring area and the second monitoring area, and will not be repeated here.

[0210] The design of the pixels in the fourth monitoring area and the fifth monitoring area can be as follows:

[0211] In a possible design, the detector 201 includes multiple monitoring areas, and the lengths of pixels in the multiple monitoring areas in the second direction are equal.

[0212] For example, the detector 201 shown in FIG16 includes a fourth monitoring area and a fifth monitoring area. The fourth monitoring area is used to receive light beams near the main optical axis, and the fifth monitoring area is used to receive light beams at other positions. The length of the pixels in the fourth monitoring area and the fifth monitoring area in the X direction are the same, both being 12. In addition, the present application does not limit the length of the pixels in the fourth monitoring area and the fifth monitoring area in the second direction. For example, in the second direction, the length of the pixels in the fourth monitoring area and the fifth monitoring area can also be 6, 8, 10 or 14, etc., as long as it is ensured that in the second direction, the length of the pixels in the fourth monitoring area is less than or equal to the length of the pixels in the fifth monitoring area.

[0213] Since the cylindrical lens diverges the light beam received by the detector 201 in the second direction, combined with the configuration of pixels of the detector 201 in the fourth monitoring area and the fifth monitoring area, it can ensure that the corresponding imaging of the fourth monitoring area and the fifth monitoring area has a higher dynamic range.

[0214] Furthermore, because the cylindrical lens diverges all light beams passing through the optical element, and light beams away from the principal optical axis are also affected by field curvature, when configuring the detector pixels, the length of the fourth monitoring area in the second direction can be set to be less than or equal to the length of the fifth monitoring area in the second direction. For example, the length of pixels in the fourth monitoring area in the second direction is 12, the length of pixels in the fifth monitoring area in the second direction is 14, and so on.

[0215] In another possible design, in the first direction, the length of pixels in the fourth monitoring area is smaller than the length of pixels in the fifth monitoring area.

[0216] As shown in Figure 16, in the Y direction (first direction), the length of the pixels in the fourth monitoring area is 3, and the length of the pixels in the fifth monitoring area is 6. The smaller the length of the pixels in the first direction, the more pixels can be generated in the first direction within the same length, which can improve the imaging resolution. Therefore, the imaging resolution corresponding to the fourth monitoring area of ​​the detector 201 shown in Figure 16 will be higher than the imaging resolution corresponding to the fifth monitoring area. In addition, the present application does not limit the length of the pixels in the fourth monitoring area and the fifth monitoring area in the first direction. For example, in the first direction, the length of the pixels in the fourth monitoring area can also be 1, 2, 4, 5, 6 or 7, and the length of the pixels in the fifth monitoring area can also be 3, 4, 5, 6, 7 or 8, etc., as long as it is ensured that in the first direction, the length of the pixels in the fourth monitoring area is greater than the length of the pixels in the fifth monitoring area.

[0217] It should be noted that FIG16 is merely an exemplary illustration of a design of the detector 201. The detector 201 may include more or fewer pixels, and each pixel may have a different configuration. For details, please refer to the design illustrated above. Therefore, FIG16 should not be construed as limiting the present application.

[0218] As can be seen from the detector 201 shown in Figure 16 , the detector 201 includes a fourth monitoring area and a fifth monitoring area, and these areas occupy all detection units in the detector 201. Combined with Figure 6B , it can be seen that under ideal imaging conditions, the light spot formed by the first light beam on the detector is a single line spot, and not all detection units on the detector are required. Furthermore, due to design errors in optical components, background noise may be introduced, interfering with the imaging results.

[0219] To this end, the present invention also provides another design for a detector 201. As shown in FIG17 , the detector 201 includes a fourth monitoring area, a fifth monitoring area, and a sixth monitoring area. The fourth and fifth monitoring areas are used to receive light beams passing through the optical element. For detailed descriptions, please refer to the fourth and fifth monitoring areas shown in FIG16 , and will not be repeated here.

[0220] The sixth monitoring area is covered by an obstruction to prevent the detection unit in the sixth monitoring area from receiving stray light beams, thereby interfering with the imaging of the fourth monitoring area and the fifth monitoring area. For example, the detection unit in the sixth monitoring area can be prevented from receiving stray light beams by means of silk screen printing, coating, electroplating, or dispensing. Regarding the configuration of the elements in the sixth monitoring area, the embodiment of the present application does not limit it. What is shown in FIG17 is only exemplary, and the content shown in FIG17 should not be used as a limitation of the present application. For example, the configuration of the elements in the sixth monitoring area can be 6×6, 3×12, etc. Since the elements in the sixth monitoring area do not receive light beams, they may not be configured.

[0221] Furthermore, this application does not impose any limitation on the number of pixels in the second direction when the detector 201 receives a line beam. The detector 201 shown in FIG17 receives a line beam and generates eight columns of pixels in the second direction. In specific implementations, the detector 201 may receive a line beam and generate one, ten, twenty, fifty, or ninety columns of pixels in the second direction, and this application does not impose any limitation on this.

[0222] Next, configurations of different monitoring areas in the first direction in the above three design solutions are exemplarily introduced.

[0223] Combined with the above description, it can be seen that in the first direction, the spread of the light beam is only affected by field curvature, so the degree of light beam spread is related to the magnitude of the field curvature. Furthermore, the first or fourth monitoring area is used to receive light beams near the principal optical axis (light beams whose spread in the first direction is less than a specified threshold). Therefore, the number of pixels in the first or fourth monitoring area in the first direction depends on the field curvature of the optical element. Referring to Figure 6D , when the field curvature of the optical element is large, the light beam at a distance d1 from the principal optical axis is significantly affected by the field curvature, meaning that light spot A cannot be properly focused, or the degree of focus of light spot A cannot meet the imaging requirements. In this case, the number of pixels in the first direction of the first or fourth monitoring area should be small, so that the light beams received by the first or fourth monitoring area can be well focused and meet the user's imaging requirements. Of course, when the field curvature of the optical element is small, the light beam at a distance d1 from the principal optical axis is less affected by the field curvature, meaning that light spot A can still be well focused, or the degree of focus of light spot A can still meet the imaging requirements. In this case, the number of pixels in the first direction of the first monitoring area or the fourth monitoring area should be large, so that the light beams received by the first monitoring area or the fourth monitoring area can be better focused to meet the user's imaging needs.

[0224] Exemplarily, the first monitoring area and the fourth monitoring area may be used as ROI areas.

[0225] In design solutions one and two, the first monitoring area in the detector 201 is used to receive the light beam near the main optical axis of the optical element. In design solution one, the light beam near the main optical axis is mainly diffused by the astigmatism in the second direction, and in design solution two, the light beam near the main optical axis is mainly diffused by the micro-cylindrical lens array in the second direction. In the first direction, the light beam near the main optical axis is less disturbed by the phase difference, so high-resolution imaging can be obtained. Combined with the configuration of pixels in the first monitoring area, it can be ensured that the dynamic range of the imaging corresponding to the first monitoring area does not decrease. In design solution three, the light beam passing through the optical element is diffused in the second direction by the cylindrical lens, and the light beam near the main optical axis is less disturbed by the phase difference in the first direction. Combined with the configuration of pixels in the fourth monitoring area, the imaging corresponding to the fourth monitoring area has high resolution while ensuring that the dynamic range does not decrease. In addition, the above three design solutions are simple in structure, the optical elements do not require complex manufacturing processes, and the manufacturing cost is low. In summary, the receiving module provided in this application utilizes a one-dimensional scanning structure of a linear spot to achieve high-resolution reception of a laser radar and realize a low-cost design of a high-resolution laser radar. In addition, since the receiving module provided in this application is a one-dimensional scanning structure based on a linear light spot and the receiving module does not require complex optical elements, the receiving module provided in this application is also conducive to the miniaturization design of high-resolution lidar.

[0226] The present application also provides a radar, comprising the aforementioned detection device 10, or the aforementioned receiving module 200, or the aforementioned detector 201. In one possible embodiment, the radar is, for example, a laser radar. For example, the transmitting module and receiving module of the laser radar can be coaxial, as shown in FIG4 , or off-axis, as shown in FIG5 , although this application does not limit this.

[0227] An embodiment of the present application also provides a terminal device, which includes the aforementioned detection device 10, or includes the aforementioned receiving module 200, or includes the aforementioned detector 201, or includes the aforementioned laser radar.

[0228] Optionally, the terminal device can be an intelligent terminal or transportation tool such as a vehicle, drone, or robot, or the terminal device can also be an industrial device. It should be understood that the terminal devices involved in this application may include intelligent terminals or transportation tools such as vehicles, robots, drones, ships, and ships. Among them, the vehicle is a vehicle in a broad sense, which can be a transportation tool (such as a commercial vehicle, passenger car, motorcycle, flying car, train, etc.), an industrial vehicle (such as a forklift, trailer, tractor, etc.), an engineering vehicle (such as an excavator, bulldozer, crane, etc.), an agricultural equipment (such as a mower, harvester, etc.), etc. For example, the robot can be an intelligent handling robot (automated guided vehicle, AGV), a walking conversational robot, a service robot, etc. Industrial equipment includes industrial robots, robotic arms, etc. Leisure and entertainment equipment includes virtual reality (VR) equipment, mixed reality (MR) equipment, or a 4D cinema cabin, etc.

[0229] Optionally, the detection device can be installed in a variety of possible locations, such as on the platform of the vehicle's dashboard, or on the head of the vehicle (as shown in Figure 1), or on the top of the cabin, the side of the vehicle, the rear of the vehicle, etc.

[0230] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A receiving module, characterized in that, The receiving module includes: an optical element and a detector, where the detector is located at the target focal plane of the optical element; The receiving module is configured to receive a first light beam, and the first light beam is a linear light beam extending along a first direction; The optical element is configured to astigmatize the first light beam in a second direction, and / or, the optical element is configured to field curve the first light beam; the first direction is perpendicular to the second direction; The detector is configured to receive the light beam that has passed through the optical element, and the detector includes a plurality of monitoring regions, and the pixel shapes of the plurality of monitoring regions are different.

2. The receiving module according to claim 1, wherein, The plurality of monitoring regions include a first monitoring region and a second monitoring region; In the first direction, the length of the pixels in the first monitoring region is less than the length of the pixels in the second monitoring region.

3. The receiving module according to claim 1 or 2, characterized in that The plurality of monitoring regions include a first monitoring region and a second monitoring region; In the second direction, the length of the pixels in the first monitoring region is greater than the length of the pixels in the second monitoring region.

4. The receiving module according to any one of claims 1-3, characterized in that The plurality of monitoring regions include a first monitoring region and a second monitoring region; The areas of the pixels in the first monitoring region and the second monitoring region are equal.

5. The receiving module according to claim 1 or 2, characterized in that, The plurality of monitoring regions include a first monitoring region and a second monitoring region; In the second direction, the length of the pixels in the first monitoring region is equal to the length of the pixels in the second monitoring region.

6. The receiving module according to any one of claims 1-5, characterized in that, The plurality of monitoring regions include a first monitoring region; For the pixels in the first monitoring region, the length a in the first direction and the length b in the second direction satisfy the following relationship: b = L * a, where L is greater than or equal to 2.

7. The receiving module according to any one of claims 1-6, characterized in that, The plurality of monitoring regions include a third monitoring region, and the third monitoring region is covered by an occluder.

8. The receiving module according to any one of claims 1-4, characterized in that, The optical element is configured to astigmatize the first light beam in a second direction, and the optical element is configured to field curve the first light beam.

9. The receiving module according to any one of claims 2-4, characterized in that, The optical element is configured to field curve the first light beam; A microlens array is disposed on the first monitoring region, and the microlens array is configured to diffuse the light beam that has passed through the optical element in the second direction.

10. The receiving module according to claim 5, wherein The optical element is configured to field curve the first light beam, and the receiving module further includes a cylindrical lens; The cylindrical lens is disposed between the optical element and the detector, and the cylindrical lens is configured to diffuse the light beam that has passed through the optical element in the second direction.

11. The receiving module according to any one of claims 1-10, characterized in that, The first direction depends on the target focal plane.

12. The receiving module according to any one of claims 1-11, characterized in that, The number of detection units in the pixel depends on the area of the detection unit, and the detection unit is the smallest unit for the detector to receive the light beam.

13. The receiving module according to claim 12, wherein The detection unit includes one or more of the following: single photon avalanche diode SPAD, silicon photomultiplier SiPM, multi-pixel photon counter MPPC, semiconductor avalanche photodiode APD, or "p-i-n" PIN diode.

14. The receiving module according to any one of claims 1-8, characterized in that, The target focal plane is a meridional focal plane or a sagittal focal plane.

15. The receiving module according to claim 14, wherein When the target focal plane is a meridional focal plane, the first direction is the vertical direction, and the second direction is the horizontal direction; When the target focal plane is the sagittal focal plane, the first direction is the horizontal direction and the second direction is the vertical direction.

16. A detection device, characterized in that, The detection device includes a transmitting module and a receiving module; wherein, the transmitting module is configured to emit a linear light beam, and the receiving module is configured to receive the linear light beam reflected by an object; the receiving module includes the receiving module according to any one of claims 1-15.

17. A radar, characterized in that, The radar includes the receiving module according to any one of claims 1-15.

18. A terminal device, characterized in that, The terminal device includes the receiving module according to any one of claims 1-15, or the detection device according to claim 16, or the radar according to claim 17.

19. A car end, characterized in that, The vehicle end includes the receiving module according to any one of claims 1-15, or the detection device according to claim 16, or the radar according to claim 17, or the terminal device according to claim 18.

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