Receiving module, laser radar and robot

Abstract

The utility model provides a receiving module, a laser radar and a robot. The receiving module comprises a focusing assembly and a detection assembly which are arranged in sequence. The focusing assembly comprises at least one micro-lens array structure, the micro-lens array structure comprises at least one micro-lens array, and the micro-lens array is used for receiving the echo light beams reflected by the target object and converging the echo light beams. The detection assembly is used for receiving the echo light beam transmitted by the micro-lens array and generating an electric signal according to the echo light beam. By adjusting the shapes, sizes and the like of the microlenses on the microlens array, the field angle and the optical efficiency can be improved, and the size and the cost of the system can be reduced.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of lidar, and particularly to a receiving module, a lidar, and a robot. Background Art

[0002] Benefiting from the characteristics of high directivity, high monochromaticity, high coherence, etc. of lasers, lidar technology can achieve long-distance anti-interference detection and is of great significance in medical treatment, atmospheric monitoring, geological mapping, urban modeling, intelligent driving, etc.

[0003] In lidar, ranging can be performed based on principles such as the Direct Time of Flight (DTOF) principle or the triangulation method. In the DTOF principle, the time difference between the emission and reception of a laser beam is used to calculate the flight time of light, thereby calculating the distance to the target object. In the triangulation method, when a laser irradiates an object, the reflected light is received by a detector. Since a fixed distance is maintained between the laser and the detector, objects at different distances will form different imaging positions on the detector. Through this imaging position, the actual distance of the object can be calculated according to the triangulation formula. In the above-mentioned lidar, it is not only required that the laser emission device can generate a narrow pulse and a highly directional laser beam, but also required that the receiving device can efficiently collect the reflected light.

[0004] However, currently, a single lens or a lens group is usually used in the receiving system of lidar to focus and collect light, resulting in limited field of view and optical efficiency of the receiving sensor, and may increase the system volume and cost. Summary of the Utility Model

[0005] The embodiments of the present application provide a receiving module, a lidar, and a robot, which can improve the field of view angle and optical efficiency, and reduce the system volume and cost.

[0006] In a first aspect, the embodiments of the present application provide a receiving module, which includes a focusing component and a detection component arranged in sequence. The focusing component includes at least one microlens array structure, and the microlens array structure includes at least one microlens array. The microlens array is used to receive the echo beam reflected by the target object and converge the echo beam. The detection component is used to receive the echo beam transmitted by the microlens array and generate an electrical signal according to the echo beam.

[0007] In some embodiments, the microlens array structure includes a substrate and a microlens array. The substrate has a first side away from the detection component and a second side close to the detection component. The microlens array is arranged on the first side or the second side; alternatively, the microlens array structure includes a substrate and two microlens arrays, and the two microlens arrays are respectively arranged on the first side and the second side.

[0008] In some embodiments, the microlens array is a refractive microlens array or a diffractive microlens array.

[0009] In some embodiments, the microlens array is a refractive microlens array, and the focusing component further includes a Fresnel lens; the Fresnel lens is disposed between the microlens array structure and the detection component.

[0010] In some embodiments, the microlens array is used to adjust the spot shape and energy density of the echo beam output onto the detection component.

[0011] In some embodiments, the microlens array includes an antireflection film; the antireflection film is disposed on the surface of the microlens.

[0012] In some embodiments, the microlens array includes a plurality of microlenses, and the shapes of the microlenses are regular shapes or irregular shapes.

[0013] In some embodiments, the microlens array includes a plurality of microlenses, and the central thickness CT of the microlens and the interval d1 between two adjacent microlenses satisfy the following relationship:

[0014]

[0015] In a second aspect, an embodiment of the present application further provides a lidar, which includes a transmitting module and the receiving module as described in any one of the first aspect. The transmitting module is configured to emit a detection beam and direct the detection beam towards a target object; the receiving module is configured to receive an echo beam reflected by the target object.

[0016] In a third aspect, an embodiment of the present application further provides a robot, which includes the lidar as described in the second aspect.

[0017] Compared with the prior art, the beneficial effects of the present application are as follows: Different from the prior art, the present application provides a receiving module, a lidar, and a robot. The receiving module includes a focusing component and a detection component arranged in sequence. The focusing component includes at least one microlens array structure, and the microlens array structure includes at least one microlens array. The microlens array is configured to receive an echo beam reflected by a target object and converge the echo beam. The detection component is configured to receive the echo beam transmitted through the microlens array and generate an electrical signal according to the echo beam. By adjusting optical parameters such as the shape and size of the microlenses on the microlens array, the spot size and energy density of the echo beam incident on the detection component can be adjusted, thereby improving the field of view angle and optical efficiency. Moreover, the microlens array has a small volume, which can reduce the system volume and cost. Description of the Drawings

[0018] In one or more embodiments, exemplary illustrations are provided through the pictures in the corresponding attached drawings. These exemplary illustrations do not constitute limitations on the embodiments. Elements / modules and steps with the same reference numerals in the attached drawings are represented as similar elements / modules and steps. Unless otherwise stated, the figures in the attached drawings do not constitute a scale limitation.

[0019] Figure 1 is a structural block diagram of a receiving module provided by an embodiment of the present application;

[0020] Figure 2 is a structural diagram of a receiving module provided by an embodiment of the present application;

[0021] Figure 3 is a structural diagram of another receiving module provided by an embodiment of the present application;

[0022] Figure 4 is a relationship diagram between spot size and energy density provided by an embodiment of the present application;

[0023] Figure 5 is another relationship diagram between spot size and energy density provided by an embodiment of the present application;

[0024] Figure 6 is yet another relationship diagram between spot size and energy density provided by an embodiment of the present application;

[0025] Figure 7 is a structural block diagram of a lidar provided by an embodiment of the present application;

[0026] Figure 8 is a structural block diagram of a transmitting module provided by an embodiment of the present application. Detailed implementation manners

[0027] To facilitate the understanding of the present application, the present application will be described in more detail below with reference to the attached drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more intermediate elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more intermediate elements therebetween. The terms "upper", "lower", "inner", "outer", "vertical", "horizontal", etc. used in this specification indicate the orientation or positional relationship based on the orientation or positional relationship shown in the attached drawings. They are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation on the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0028] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0029] In addition, the technical features involved in different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0030] In a first aspect, this application provides a receiving module 100. Refer to Figure 1 and Figure 2 , the receiving module 100 includes a focusing component 10 and a detection component 20 arranged in sequence. The focusing component 10 includes at least one microlens array structure 11, and the microlens array structure 11 includes at least one microlens array. The microlens array is used to receive the echo beam L1 reflected by the target object and converge the echo beam L1. The detection component 20 is used to receive the echo beam L1 transmitted through the microlens array and generate an electrical signal according to the echo beam L1.

[0031] The echo beam L1 refers to the beam that after the detection beam emitted by the lidar irradiates the surface of the target object, due to the inconsistent surface reflectivity and roughness flatness of different objects, is diffusely reflected by the surface of the target object to the lidar. The detection component 20 is a device that can respond to optical signals, such as converting optical signals into electrical signals.

[0032] The microlens array includes a plurality of microlenses arranged in an array. A microlens refers to a lens with a through-aperture and a relief depth at the nanometer level. The microlens can be an injection-molded microlens or a glass microlens. An injection-molded microlens refers to a microlens made of plastic material, and a glass microlens refers to a microlens made of glass material. The microlens array can split the incident echo beam L1 into multiple beams and converge the beams. When designing the microlens, it can be designed to focus beams of different wavelengths simultaneously.

[0033] In this receiving module 100, the echo beam L1 will reach the detection component 20 after being converged by the microlens array. By designing the microlenses in the microlens array of the microlens array structure 11, the optical properties such as the homogenization ability and the convergence ability of the microlens array can be adjusted, so that the spot size and energy density of the echo beam L1 reaching the detection component 20 can be adjusted, which helps to expand the field of view and increase the depth of field, and makes the echo beam L1 more evenly distributed on the detection component 20, reducing the interference of ambient light and background noise, and improving the detection accuracy and range of the detection component 20. And the microlens array has a smaller volume than the traditional lens group, which is beneficial to the miniaturization of the optical system and the improvement of the integration degree, and can reduce the manufacturing cost.

[0034] In some of these embodiments, referring to Figure 2 , the receiving module 100 further includes a filtering component 30. The filtering component 30 is disposed between the focusing component 10 and the detecting component 20. The filtering component 30 is configured to receive the echo beam L1 and transmit the echo beam L1 within a preset wavelength band range to the detecting component 20.

[0035] The filtering component 30 may include optical devices such as a filter that can filter wavelength bands. The filter can selectively transmit and block light within a specific wavelength range. In some embodiments, the preset wavelength band range may be a wavelength band range greater than or equal to 800 nm and less than or equal to 1000 nm. That is, the transmittance of the filter for the echo beam L1 within the wavelength band range greater than or equal to 800 nm and less than or equal to 1000 nm is close to 100%, and the reflectance of the filter for the echo beam L1 not within the above range is close to 0%. The substrate material of the filter can use glass material. To improve the efficiency of the filtering component 30 on the light beam, the area of the filter should be larger than the cross-sectional size of the echo beam L1 to ensure that the filter can filter all the echo beams L1.

[0036] In this embodiment, by providing the filtering component 30, the light beam within the preset wavelength band range in the echo beam L1 can be separated, thereby improving the detection efficiency of the detecting component 20, reducing the interference of ambient light and stray light, and improving the detection accuracy.

[0037] In some of these embodiments, the detecting component 20 includes a single-photon avalanche diode (SPAD) photosensitive array. The SPAD photosensitive array includes SPAD sensors arranged in an array, and the SPAD sensors can be used to convert the echo beam L1 into an electrical signal. In this embodiment, by providing the SPAD photosensitive array as the detecting component 20, the detection of the echo beam L1 can be achieved.

[0038] In some of these embodiments, the microlens array is used to adjust the spot shape and energy density of the echo beam output to the detecting component.

[0039] Specifically, in the design of a microlens array, the optical performance of the microlens array can be adjusted by adjusting parameters such as the shape, focal length, arrangement structure, and duty cycle of the microlenses. In some embodiments, the shape of the microlens refers to the cross-sectional shape of the microlens, and the shape of the microlens can be regular shapes such as square, circular, elliptical, and hexagonal, or irregular shapes can be adopted. The focal length of the microlens refers to the distance at which the microlens focuses parallel light into a focal point. The arrangement structure of the microlenses refers to the layout dimensions of the microlenses in the microlens array. For example, when the shape of the microlens is circular, the arrangement structure of the microlenses can include parameters such as the refractive index of the microlens, the central thickness of the microlens, and the spherical curvature of the microlens. The duty cycle of the microlens refers to the ratio of the area occupied by the microlens to the area of the entire array.

[0040] In scenarios with high light requirements, the sensors of the detection components of traditional receiving modules will experience saturation, resulting in a decrease in ranging accuracy. In this application, by adjusting parameters such as the shape, focal length, arrangement structure, and duty cycle of the microlenses in the microlens array structure 11, the spot shape and energy density of the echo beam L1 on the detection component 20 can be reduced to within a certain threshold, avoiding saturation of the sensors of the detection component 20 and improving the ranging ability. At the same time, in practical applications, the parameters such as the shape, focal length, arrangement structure, and duty cycle of the microlenses in the microlens array structure 11 can be adjusted according to actual needs to improve the flexibility of the design.

[0041] In some of these embodiments, referring to Figure 2 , the microlens array structure 11 includes a substrate and a microlens array. The substrate has a first side close to the target object and far from the detection component 20 and a second side close to the detection component 20 and far from the target object. The microlens array is disposed on the first side or the second side; or, referring to Figure 3 , the microlens array structure 11 includes a substrate and two microlens arrays, and the two microlens arrays are respectively disposed on the first side and the second side of the substrate.

[0042] In this embodiment, the user can set the microlens array on the first side and / or the second side of the substrate according to actual needs to improve the design flexibility of the microlens array structure 11 in practical applications. Compared with the embodiments in which the microlens array is only disposed on the first side or the second side of the substrate, the embodiment in which the microlens arrays are disposed on both the first side and the second side of the substrate can improve the collection effect and homogenization efficiency of the microlens array structure 11 for the echo beam L1.

[0043] In some of these embodiments, the microlens array is a refractive microlens array or a diffractive microlens array. In a refractive microlens array, the microlenses focus light based on the refraction principle of geometric optics, following Snell's law of refraction. That is, when the echo beam L1 passes through the refractive microlens array, the echo beam L1 undergoes a refraction effect on the microlenses. In a diffractive microlens array, the microlenses focus light based on the diffraction principle of physical optics. That is, when the echo beam L1 passes through the diffractive microlens array, the echo beam L1 is modulated by the surface relief microstructures on the microlens array to change the wavefront phase, thereby realizing the modulation and transformation of light waves.

[0044] In this embodiment, by using a refractive microlens array or a diffractive microlens array as the focusing component 10, users can select the device according to actual needs, improving the design flexibility in practical applications.

[0045] In some of these embodiments, referring to Figure 2 or Figure 3 , the microlens array is a refractive microlens array, and the focusing component 10 further includes a Fresnel lens 12. The Fresnel lens 12 is disposed between the microlens array structure 11 and the detection component 20.

[0046] The material of the Fresnel lens 12 is an injection-molded Fresnel lens or a glass Fresnel lens. An injection-molded Fresnel lens refers to a Fresnel lens made of plastic material, and a glass Fresnel lens refers to a Fresnel lens made of glass material. When designing the Fresnel lens 12, it can be made to focus beams of different wavelengths simultaneously. In some embodiments, the receiving module 100 is applied to a lidar. To improve the receiving efficiency, an anti-reflection film can be coated on the surface of the Fresnel lens 12. The anti-reflection film can be used to reduce the reflection of beams within a preset wavelength range and increase the transmission of beams within the preset wavelength range. The preset wavelength range can be the wavelength range of the detection beam emitted by the transmitting module of the lidar.

[0047] In this receiving module 100, by using the microlens array structure 11 and the Fresnel lens 12 together to focus light, the focusing effect on the echo beam L1 can be improved.

[0048] In some of these embodiments, the receiving module 100 further includes a fixing bracket. The focusing component 10 and the detection component 20 are disposed on the fixing bracket. Specifically, the microlens array, the Fresnel lens 12, and the detection component 20 can be installed on the fixing bracket at a certain interval. By using the fixing bracket to install the focusing component 10 and the detection component 20, the distance between the focusing component 10 and the detection component 20 can be ensured to meet a preset relationship, thereby ensuring that the detection component 20 can normally detect the echo beam L1.

[0049] In some of these embodiments, the microlens array includes an antireflection film disposed on the surface of the microlens. The antireflection film can be used to reduce the reflection of light beams within a preset wavelength range and increase the transmission of light beams within the preset wavelength range. The preset wavelength range can be the wavelength range of the detection light beam emitted by the emission module of the lidar, such as a wavelength range greater than or equal to 800 nm and less than or equal to 1000 nm.

[0050] In this embodiment, by providing the antireflection film, the light beam within the preset wavelength range in the echo light beam L1 can be separated, thereby improving the detection efficiency of the detection component 20, reducing the interference of ambient light and stray light, and improving the detection accuracy.

[0051] In some of these embodiments, the microlens array includes a plurality of microlenses, and the central thickness CT of the microlens and the distance d1 between two adjacent microlenses satisfy the following relationship:

[0052]

[0053] Refer to Figure 3 , the central thickness CT of the microlens refers to the thickness of the central part of the microlens, which can be the maximum thickness of the microlens in the direction perpendicular to the substrate plane, and the distance d1 between two adjacent microlenses refers to the distance between the centers of two adjacent microlenses.

[0054] In this embodiment, by making the size of the microlens satisfy the above relationship, the complexity of the production process can be reduced.

[0055] Next, the working process of the receiving module 100 provided by the present application will be elaborated in detail in combination with the embodiments shown in Figure 3 . In the embodiments shown in Figure 3 , the central thickness CT of the microlens and the distance d1 between two adjacent microlenses satisfy the aforementioned relationship. The microlens array structure 11 includes a substrate and two microlens arrays, and the two microlens arrays are respectively disposed on both sides of the substrate. Among them, the microlenses on the two microlens arrays are all circular, the structures of the microlenses on the same side are the same, that is, the spherical curvature radii and focal lengths of the microlenses on the same side are the same, and the refractive indices of the microlenses on both sides are n L . Then, the effective focal length fla1 of the microlens array structure 11 satisfies the following relationship:

[0056]

[0057] Among them, R1 is the spherical curvature radius of the microlens on the first side, and R2 is the spherical curvature radius of the microlens on the second side. In this receiving module 100, after the echo beam L1 passes through each microlens on the microlens array structure 11, it will be further focused on the detection component 20 by the Fresnel lens 12, and the focused points re-form an array arrangement. The incident beam can be approximately regarded as a beam array corresponding to the microlens array. The multiple small beams refocused by the microlens array structure 11 are superimposed on each other. Based on the symmetry of the array arrangement, the non-uniformity of the small beams cancels each other out. After further focusing by the Fresnel lens 12 and filtering by the filtering component 30, a uniform light spot is finally formed on the detection surface of the detection component 20. The size D3 of the light spot satisfies the following relationship:

[0058] D3 = Pla * f / fla1;

[0059] Among them, Pla is the aperture size of the microlens, f is the focal length of the Fresnel lens 12, and fla1 is the effective focal length of the microlens array structure 11. It can be seen that the size D3 of the light spot is related to the effective focal length fla1 of the microlens array structure 11, and the effective focal length fla1 of the microlens array structure 11 is related to the spherical curvature radius R1 of the microlens on the first side, the spherical curvature radius R2 of the microlens on the second side, the refractive index n of the microlens L , the central thickness CT of the microlens, and the interval d1 between two microlenses. Therefore, the size D3 of the light spot can be adjusted by adjusting the above parameters of the microlens array structure 11.

[0060] Specifically, under the condition that the total energy of the echo beam L1 incident on the microlens array structure 11 is consistent, when the effective focal length fla1 of the microlens array structure 11 is 7 mm, refer to Figure 4 , the length and width of the light spot are both 0.64 mm, and the energy density is 120 w / mm^2 to 125 w / mm^2. When the effective focal length fla1 of the microlens array structure 11 is 11 mm, refer to Figure 5 , the length and width of the light spot are both 0.4 mm, and the energy density is 300 w / mm^2 to 350 w / mm^2. When the effective focal length fla1 of the microlens array structure 11 is 17 mm, refer to Figure 6, the length and width of the light spot are both 0.26 mm, and the density is 625 - 650 w / mm^2. It can be seen that by adjusting the size of the microlens array structure 11, the effective focal length of the microlens array structure 11 can be adjusted, so that the shape and energy density of the light spot incident on the detection component 20 can be controlled, and by adjusting the shape and energy density of the light spot on the detection component 20. In scenarios with strong light requirements, the sensors of the detection components of traditional receiving modules will be saturated, resulting in a decrease in ranging accuracy. In this application, by adjusting the microlens array structure 11, the energy density of the light spot on the detection component 20 can be reduced to within a certain threshold, avoiding the saturation of the sensors of the detection component 20 and improving the ranging ability.

[0061] In summary, the receiving module 100 provided by this application can adjust the optical properties such as the homogenization ability and convergence ability of the microlens array by designing the optical parameters such as the shape, focal length, arrangement structure, and duty cycle of the microlens array of the microlens array structure 11, so as to adjust the size and energy density of the light spot when the echo beam L1 reaches the detection component 20, which helps to expand the field of view angle and increase the depth of field, and makes the echo beam L1 more evenly distributed on the detection component 20, reducing the interference of ambient light and background noise, and improving the detection accuracy and range of the detection component 20. Moreover, the microlens array is smaller in volume than the traditional lens group, which is beneficial to the miniaturization of the optical system and the improvement of integration, and can reduce the manufacturing cost.

[0062] In a second aspect, this application also provides a lidar 1000. Refer to Figure 7 , the lidar 1000 includes a transmitting module 200 and the receiving module 100 as described in any one of the embodiments of the first aspect. The transmitting module 200 is configured to emit a detection beam L2 and direct the detection beam L2 towards the target object 2000. The receiving module 100 is configured to receive the echo beam L1 reflected by the target object 2000.

[0063] In this embodiment, the receiving module 100 has the same structure and function as the receiving module 100 described in any one of the first aspects, and will not be described in detail here.

[0064] In some of these embodiments, refer to Figure 8 , the transmitting module 200 includes a Vertical-External-Cavity Surface-Emitting Laser (VECSEL) 210 and a shaping lens 220. The VECSEL 210 is configured to emit the detection beam L2 to the shaping lens 220. The shaping lens 220 is configured to shape the detection beam L2 and direct the shaped detection beam L2 towards the target object 2000.

[0065] The VECSEL210 combines the advantages of solid-state lasers and semiconductor lasers, and can simultaneously achieve high output power and high beam quality. In addition, the VECSEL210 has a flexible external cavity structure, and various optical elements can be added to the cavity to realize functions such as wavelength tuning, mode locking, and nonlinear frequency conversion. The wavelength range λ1 of the detection beam L2 emitted by the VECSEL210 satisfies the following relationship:

[0066] 800nm ≤ λ1 ≤ 1000nm.

[0067] The shaping lens 220 may include a beam expander lens and / or a collimating lens, so as to expand and / or collimate the detection beam L2. The shaping lens 220 can be an injection-molded lens or a glass lens. An injection-molded lens refers to a lens made of plastic material, and a glass lens refers to a lens made of glass material. An antireflection film is coated on the surface of the shaping lens 220. The antireflection film can be used to reduce the reflection of the beam in the preset wavelength range and increase the transmission of the beam in the preset wavelength range. The preset wavelength range can be the wavelength range of the detection beam emitted by the emission module of the lidar, such as the wavelength range from 800nm to 1000nm.

[0068] In the emission module 200, the VECSEL210 is a surface array light source or a point light source, and can output a detection beam L2 with a certain divergence angle. The detection beam L2 propagates in space at a certain divergence angle. After being shaped by the shaping lens 220, it becomes parallel light with a spot diameter D1. The parallel light propagates in space to the target object 2000, and then the light beam is diffusely reflected back into the lidar 1000 and reaches the detection component 20 through devices such as the microlens array structure 11 in the receiving module 100, so that the optical signal can be processed to realize detection.

[0069] In the lidar 1000, by designing the optical parameters such as the shape, focal length, arrangement structure, and duty cycle of the microlens array of the microlens array structure 11 in the receiving module 100, the homogenization ability, focusing ability, and other optical properties of the microlens array can be adjusted, so that the spot size and energy density of the echo beam L1 reaching the detection component 20 can be adjusted.

[0070] In a third aspect, an embodiment of the present application further provides a robot, and the robot includes the lidar as described in any one of the embodiments of the second aspect. In this embodiment, the lidar has the same structure and function as the lidar described in any one of the second aspects, and will not be described in detail here. Among them, the robot may include, but is not limited to, a floor washer, a sweeper, an intelligent transport trolley, etc.

[0071] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; under the idea of the present application, the technical features in the above embodiments or different embodiments can also be combined, and the steps can be implemented in any order, and there are many other variations in different aspects of the present application as described above. For the sake of brevity, they are not provided in detail; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A receiving module, characterized in that, Comprising a focusing component and a detection component arranged in sequence; The focusing component includes at least one microlens array structure, the microlens array structure includes at least one microlens array, and the microlens array is used to receive the echo beam reflected by the target object and converge the echo beam; The detection component is used to receive the echo beam transmitted by the microlens array and generate an electrical signal according to the echo beam.

2. The receiving module according to claim 1, wherein, The microlens array structure includes a substrate and one microlens array, the substrate has a first side away from the detection component and a second side close to the detection component, and the microlens array is arranged on the first side or the second side; Alternatively, the microlens array structure includes the substrate and two microlens arrays, and the two microlens arrays are respectively arranged on the first side and the second side.

3. The receiving module according to claim 2, wherein The microlens array is a refractive microlens array or a diffractive microlens array.

4. The receiving module according to claim 3, wherein The microlens array is a refractive microlens array, and the focusing component further includes a Fresnel lens; The Fresnel lens is arranged between the microlens array structure and the detection component.

5. The receiving module according to any one of claims 1-4, characterized in that, The microlens array is used to adjust the spot shape and energy density of the echo beam output to the detection component.

6. The receiving module according to claim 5, wherein The microlens array includes an anti-reflection film; The anti-reflection film is arranged on the surface of the microlens.

7. The receiving module according to claim 5, wherein The microlens array includes a plurality of microlenses, and the shape of the microlenses is a regular shape or an irregular shape.

8. The receiving module according to claim 5, characterized in that, The microlens array includes a plurality of microlenses, and the central thickness CT of the microlenses and the interval d1 between two adjacent microlenses satisfy the following relationship:

9. A lidar, characterized in that, Comprising a transmitting module and the receiving module according to any one of claims 1-8; The transmitting module is used to emit a detection beam and direct the detection beam towards the target object; The receiving module is used to receive the echo beam reflected by the target object.

10. A robot, characterized in that, Comprising a lidar according to claim 9.

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