Superlens, dodging module, dodging emitting device and machine vision system

Abstract

The utility model provides a super lens, a dodging module, a dodging emitting device and a machine vision system. The super lens comprises a substrate and a micro-nano structure arranged on the substrate, the super lens is used for receiving emitted light of the multimode optical fiber coupling light source and modulating the emitted light into a uniform light beam, and the uniform light beam forms a uniform light spot on a target plane; wherein the phase of the super lens comprises a dodging phase and a collimation phase; the light uniformizing phase is used for uniformizing the light intensity distribution of the light beam received by the super lens; and the collimation phase is used for collimating the light beam received by the super lens. According to the light uniformizing module provided by the invention, the received light beam is collimated and diffused through the super lens, so that the light uniformizing module projects the received light beam into the uniformized light spot with high edge collimation, the structure of the light uniformizing module is simplified, the size of the light uniformizing module is reduced, and the production cost of the light uniformizing module is also reduced.

Description

Technical Field

[0001] The present application relates to the field of optics, and in particular to a superlens, a uniform light module, a uniform light emitting device and a machine vision system. Background Art

[0002] The homogenization module has a wide range of application scenarios in machine vision technology. It can be used with light sources to provide uniform lighting conditions, allowing the camera to accurately capture the image of the target object; the homogenization module can also be used with light sources as the transmitter of the TOF (Time Of Flight) sensor. TOF sensors measure distance by measuring the time during light transmission and are widely used in machine vision technology. For example, they can be used to detect surface defects of devices, automatically identify and store code reading, detect characters, guide spare parts feeding, and measure the flatness and gap width of electronic products.

[0003] However, in the prior art homogenizing module, in order to project the received light beam onto the target plane or the detection object and form a homogenized light spot with a high edge steepness, the homogenizing module needs to use a collimating lens plus two mutually perpendicular cylindrical lens arrays. As a result, the structure of the entire homogenizing module is complex, the volume is large, and the production cost is high. Utility Model Content

[0004] One purpose of the present application is to propose a metalens, a homogenizing module, a homogenizing emitting device and a machine vision system, which can improve the edge steepness of the homogenized light spot projected by the homogenized light spot while simplifying the structure of the homogenizing module and reducing the volume and production cost of the homogenizing module.

[0005] According to one aspect of an embodiment of the present application, a metalens for a robot is disclosed, characterized in that the metalens includes a substrate and a micro-nano structure arranged on the substrate; the metalens is used to receive emission light from a multimode fiber-coupled light source and modulate the emission light into a uniform light beam, and the uniform light beam forms a uniform light spot on a target plane;

[0006] Among them, the phase of the superlens includes a homogenization phase and a collimation phase; the homogenization phase is used to homogenize the light intensity distribution of the light beam received by the superlens; the collimation phase is used to collimate the light beam received by the superlens.

[0007] In an exemplary embodiment of the present application, when the divergence half angle of the uniform light beam in the target direction is less than or equal to 15°, the tailing degree of the uniform light spot in the target direction is less than 1°.

[0008] In an exemplary embodiment of the present application, when the divergence half angle of the uniform light beam in the target direction is less than or equal to 37.5°, the tailing degree of the uniform light spot in the target direction is less than 2°.

[0009] According to one aspect of an embodiment of the present application, a light homogenization module for a robot is disclosed, the light homogenization module comprising: a super lens as described in any one of the above items; a housing;

[0010] Wherein, the shell is used to fix the super lens, and a light exit hole and a light entrance hole are provided on the shell;

[0011] The super lens is arranged inside the space enclosed by the shell.

[0012] In an exemplary embodiment of the present application, the light exit hole and the light entrance hole are arranged on the same optical axis.

[0013] In an exemplary embodiment of the present application, the light homogenization module further includes a fixing structure;

[0014] The fixing structure is arranged on the inner surface of the shell, and the fixing structure is used to fix the super lens.

[0015] In an exemplary embodiment of the present application, the light homogenization module further includes a protective glass;

[0016] The protective glass is arranged at the light exit hole of the housing.

[0017] In an exemplary embodiment of the present application, the size of the plane where the light exit hole is located is greater than or equal to the size of the plane where the light entrance hole is located.

[0018] According to one aspect of an embodiment of the present application, a uniform light transmitting device is disclosed, the uniform light transmitting device comprising: a multimode fiber coupled light source; a uniform light module as described in any one of the above items;

[0019] The multimode fiber-coupled light source is arranged at the light entrance hole of the shell, and the super lens is arranged at the light exit side of the multimode fiber-coupled light source.

[0020] According to one aspect of an embodiment of the present application, a machine vision system is disclosed, and the machine vision system includes: a receiving device; and a uniform light emitting device as described in any one of the above items.

[0021] The superlens for robots provided by the present application includes: a substrate and a micro-nano structure arranged on the substrate; the superlens is used to receive the emitted light of a multimode fiber-coupled light source and modulate the emitted light into a uniform light beam, and the uniform light beam forms a uniform light spot on the target plane; wherein the phase of the superlens includes a uniform light phase and a collimation phase; the uniform light phase is used to homogenize the light intensity distribution of the light beam received by the superlens; the collimation phase is used to collimate the light beam received by the superlens. The present application provides a superlens for robots, which can project the emitted light of a multimode fiber-coupled light source into a uniform light spot with high edge collimation, so that the uniform light module can achieve the homogenization and collimation of the light beam by using only one superlens, which simplifies the structure of the uniform light module, reduces the volume of the uniform light module, and also reduces the production cost of the uniform light module.

[0022] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0023] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other objects, features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

[0025] Figure 1 A schematic diagram of the structure of a metalens provided in one embodiment of the present application is shown.

[0026] Figure 2 A schematic diagram of the operation of a metalens provided in one embodiment of the present application is shown.

[0027] Figure 3 A structural schematic diagram of a light homogenization module provided in an embodiment of the present application is shown.

[0028] Figure 4 A structural schematic diagram of a light homogenization module provided in an embodiment of the present application is shown.

[0029] Figure 5 A structural schematic diagram of a light homogenization module provided in an embodiment of the present application is shown.

[0030] Figure 6 A structural schematic diagram of a light homogenization module provided in an embodiment of the present application is shown.

[0031] Figure 7 A structural schematic diagram of a light homogenization module provided in an embodiment of the present application is shown.

[0032] Figure 8A schematic structural diagram of a uniform light emitting device provided in one embodiment of the present application is shown.

[0033] Fig. 9 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 1 of the present application is shown.

[0034] Fig.10 A schematic diagram showing the light intensity of the uniform light spot projected by the uniform light emitting device provided in Example 1 of the present application in the x-center section and the y-center section is shown.

[0035] Fig.11 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 2 of the present application is shown.

[0036] Fig.12 A schematic diagram showing the light intensity of the uniform light spot projected by the uniform light emitting device provided in Example 2 of the present application in the x-center section and the y-center section is shown.

[0037] Fig.13 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 3 of the present application is shown.

[0038] Fig.14 A schematic diagram showing the light intensity of the uniform light spot projected by the uniform light emitting device provided in Example 3 of the present application in the x-center section and the y-center section is shown.

[0039] Fig.15 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 4 of the present application is shown.

[0040] Fig.16 The spatial irradiance diagram of the position of the homogenized light spot in the y direction projected by the homogenized light emitting device provided in Example 4 of the present application is shown.

[0041] Fig.17 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 5 of the present application is shown.

[0042] Fig.18 The spatial irradiance diagram of the position of the homogenized light spot in the y direction projected by the homogenized light emitting device provided in Example 5 of the present application is shown.

[0043] Reference numerals:

[0044] 1-superlens; 11-substrate; 12-micro-nanostructure; 2-housing; 3-light exit hole; 4-light entrance hole; 5-fixed structure; 6-protective glass; 7-light source; 8-emitted light; 9-homogenized light beam; 10-homogenized light spot;

[0045] A - Target plane. DETAILED DESCRIPTION

[0046] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these example embodiments are provided so that the description of the present application will be more comprehensive and complete and the concepts of the example embodiments will be fully conveyed to those skilled in the art. The accompanying drawings are only schematic illustrations of the present application and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted.

[0047] In addition, the described features, structures or characteristics may be combined in one or more example embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the example embodiments of the present application. However, those skilled in the art will appreciate that the technical solution of the present application may be practiced while omitting one or more of the specific details, or other methods, components, steps, etc. may be adopted. In other cases, known structures, methods, implementations or operations are not shown or described in detail to avoid obscuring the present application and making the various aspects of the present application obscure.

[0048] In the prior art, the light homogenization module is widely used in machine vision technology. The light homogenization module can cooperate with the light source to provide uniform lighting conditions for the camera; the light homogenization module can also cooperate with the light source as the transmitting end of the TOF sensor, so as to project the received light beam emitted by the light source onto the target plane or the detection object, and form a homogenized light spot with a high edge steepness. However, in order to realize the projecting of the received light beam onto the target plane or the detection object and form a homogenized light spot with a high edge steepness, the light homogenization module in the prior art needs to use a collimating lens plus two mutually perpendicular cylindrical lens arrays, which will lead to the problems of complex structure, large volume and high production cost of the light homogenization module.

[0049] In order to overcome the above-mentioned defects of the related art, the present application provides a superlens for a robot and a light homogenizing module equipped with a superlens, which can modulate the received light beam and form a homogenized light spot with high edge steepness at the target plane or the detection object, while simplifying the structure of the light homogenizing module, reducing the volume of the light homogenizing module and reducing the production cost.

[0050] The present application provides a metalens for a robot, such as Figure 1 As shown, Figure 1The schematic diagram of the structure of a metalens provided by an embodiment of the present application is shown. The metalens 1 includes a substrate 11 and a micro-nano structure 12 disposed on the substrate 11, and the micro-nano structure 12 is a subwavelength structure. The metalens 1 mainly configures the material, length, height, arrangement period and other parameters of the micro-nano structure 12 at each location, thereby providing a corresponding phase at each location, applying different phase mutations to the received light beam, and thus making each location on the metalens 1 have a certain phase gradient, so that the metalens 1 modulates the light beams received at different locations thereon.

[0051] In the embodiment of the present application, since the metalens 1 provided in the present application is used for a robot, a high-power multimode fiber-coupled light source is required in the field of machine vision of the robot. Therefore, the metalens 1 is used to receive the emission light of the multimode fiber-coupled light source and modulate the emission light into a uniform light beam. After the uniform light beam propagates a certain distance, a homogenized light spot is formed at the target plane.

[0052] In the embodiment of the present application, based on the superposition of the phase of the metalens, the phase of the metalens 1 includes a homogenization phase and a collimation phase; wherein the homogenization phase is used to homogenize the light intensity distribution of the light beam received by the metalens 1; and the collimation phase is used to collimate the light beam received by the metalens 1. In other words, the phase distribution of the metalens 1 in the present application within its coverage area includes a homogenization phase for homogenizing the light intensity distribution of the light beam, and a collimation phase for collimating the light beam. In this way, the edge steepness of the light beam modulated by the metalens 1 can be improved, thereby improving the edge steepness of the homogenized light spot formed by the light beam at the target plane or the detection object, so that the edge of the formed homogenized light spot is clearer and sharper.

[0053] Furthermore, the superlens 1 can also be a superlens array composed of multiple superlenses.

[0054] In one embodiment, the uniform light phase of the metalens provided in the present application is designed by an optimal transport light mapping method, and the collimation phase is obtained by optimizing and fitting using optical product design and simulation software (such as Zemax simulation software).

[0055] As an example, when the collimation phase of the metalens 1 provided in the present application is designed using Zemax simulation software, a binary surface can be constructed in the sequence mode of the Zemax simulation software to represent the collimation phase of the metalens 1, wherein the binary surface coefficient is set to the third order. Then, the wavelength and the system aperture are set in the system options, and the aperture type of the system aperture selects the object space NA to simulate the beam divergence angle of the multimode fiber coupled light source. Then, the back focus size of the metalens 1 is set by setting the position of the binary surface, and the coefficient of the binary surface is set as a variable, and the imaging quality is set to the angular direction in the optimization wizard, and the type selects PTV to optimize the binary surface third-order coefficient. After the optimization is completed, the distribution of the collimation phase of the metalens 1 can be obtained.

[0056] Furthermore, if the metalens 1 is a metalens array, after completing the distribution of the collimation phase of a sub-metalens in the metalens array according to the above example, the collimation phase binary surface is set in the non-sequential mode of the Zemax simulation software, and then a new binary surface is constructed, and the size of the binary surface is modified to a rectangle through Boolean operation, and the binary surface metalens array is obtained by arraying it. Then, the fifth-order phase coefficient of the new binary surface is set as a variable, and the fifth-order phase coefficient of the binary surface is optimized using the spatial uniformity in the non-sequential optimization wizard, so as to obtain the distribution of the collimation phase of the metalens array.

[0057] Figure 2 FIG. 4 shows a schematic diagram of the operation of a metalens provided in an embodiment of the present application. Figure 2 As shown, after the emission light 8 emitted by the light source 7 is modulated by the super lens 1, a uniform light beam 9 is obtained. After propagating a certain distance, the uniform light beam 9 forms a uniform light spot 10 on the target plane A. It should be noted that the process of homogenizing the emission light 8 by the super lens 1 is actually also a process of diffusing the emission light 8. The super lens 1 modulates the emission light 8 into a uniform light beam 9 with a certain divergence angle in the x direction and the y direction, thereby forming a uniform light spot with a certain FOI (Field Of Illumination, illumination coverage angle) on the target plane A, as shown in FIG. Figure 2 As shown, the x direction of the homogenized light beam 9 is parallel to the x axis of the superlens 1 and the homogenized light spot 10 , and the y direction of the homogenized light beam is parallel to the y axis of the superlens 1 and the homogenized light spot 10 .

[0058] In one embodiment, when the emission light 8 from the light source 7 is modulated by the superlens 1, the half angle of divergence of the obtained uniform light beam 9 in the target direction is less than or equal to 15°, and the tailing degree of the uniform light spot 10 in the target direction is less than 1°.

[0059] In one embodiment, when the emission light 8 from the light source 7 is modulated by the superlens 1, the divergence half angle of the obtained uniform light beam 9 in the target direction is less than or equal to 37.5°, and the tailing degree of the uniform light spot 10 in the target direction is less than 2°.

[0060] It should be noted that if Figure 2 As shown, the target directions of the homogenized light beam 9 and the homogenized light spot 10 include: the positive direction of the x-axis along the coordinate axis of the homogenized light spot 10 (the center of the coordinate axis is the center of the homogenized light spot 10), the negative direction of the x-axis along the coordinate axis of the homogenized light spot 10, the positive direction of the y-axis along the coordinate axis of the homogenized light spot 10, and the negative direction of the y-axis along the coordinate axis of the homogenized light spot 10.

[0061] That is to say, when the half angle of the divergence angle of the uniform light beam 9 in the positive direction of the x-axis is less than or equal to 15°, the tailing degree of the uniform light spot 10 in the positive direction of the x-axis is less than 1°; when the half angle of the divergence angle of the uniform light beam 9 in the negative direction of the x-axis is less than or equal to 37.5°, the tailing degree of the uniform light spot 10 in the negative direction of the x-axis is less than 2°; the same is true in the positive and negative directions of the y-axis, which will not be repeated here.

[0062] Moreover, in the present application, the tailing degree is a standard for reflecting the edge steepness of the homogenized light spot 10. When the tailing degree is smaller, it represents that the edge steepness of the homogenized light spot 10 is higher. The specific calculation method of the tailing degree of the homogenized light spot 10 in the target direction is: the absolute value of the difference between the FOI half angle corresponding to 10% of the maximum light intensity of the homogenized light spot 10 in the target direction and the FOI half angle corresponding to 90% of the maximum light intensity.

[0063] The present application provides a light homogenization module for a robot, such as Figure 3 As shown, Figure 3 A schematic structural diagram of a light homogenization module provided in an embodiment of the present application is shown. The light homogenization module comprises: a super lens 1 as described in the above embodiment; and a housing 2.

[0064] Specifically, the superlens 1 is used to homogenize and collimate the received light beam to form a homogenized light spot on the target plane. The shell 2 is used to fix the superlens 1. The shell 2 is provided with a light exit hole 3 and a light entrance hole 4. The superlens 1 is arranged inside the space enclosed by the shell 2.

[0065] In detail, when the light homogenizing module is working, the light beam enters the interior of the light homogenizing module from the light inlet 4 and irradiates the super lens 1. The super lens 1 applies different phase mutations to the light beams received at different positions thereon to modulate the received light beams and output the modulated light beams, that is, the light homogenizing beams. The light homogenizing beams are emitted from the light outlet 3 and form a homogenized light spot with high edge steepness at the target plane or the detection object after propagating a certain distance. Compared with the traditional light homogenizing module, the super lens provided in the present application enables the light homogenizing module to achieve the homogenization and collimation of the light beam with only one super lens, and at the same time makes the edge steepness of the finally formed homogenized light spot high, thereby simplifying the structure of the light homogenizing module and greatly reducing the volume and production cost of the light homogenizing module.

[0066] In one embodiment, the light exit hole 3 and the light entrance hole 4 are arranged on the same optical axis, so that the light beam can enter the light homogenizing module from the light entrance hole 4 and be emitted from the light exit hole 3 after being modulated by the super lens 1 .

[0067] In another embodiment, the light exit hole 3 and the light entrance hole 4 may not be arranged on the same optical axis. In this case, the metalens 1 in the light homogenizing module has the ability to form an eccentric light beam, so that the modulated light beam can be emitted from the light exit hole 3 which is not located on the same optical axis as the light entrance hole 4. In this case, the overall shape of the light homogenizing module has more options, and can be a bent structure, such as a bent shape close to an "L" shape, so that the light homogenizing module can be applied to more machine vision scenarios, and the flexibility of the use of the light homogenizing module is improved.

[0068] In another embodiment, the super lens 1 can also be arranged at the light exit hole 3 on the outer surface of the housing 2, such as Figure 4 As shown, Figure 4 FIG. 1 shows a schematic diagram of the structure of a light homogenization module provided in an embodiment of the present application. Figure 4 In the embodiment, the light incident surface of the metalens 1 is flush with the outer surface of the housing 2. In this case, the light beam enters the homogenizing module from the light incident hole 4, passes through the light exit hole 3, and then reaches the metalens 1. After the metalens 1 modulates the incident light beam, it directly emits the homogenizing light beam to the target plane or the detection object, thereby forming a homogenized light spot with clear and sharp edges. In this case, the processing difficulty of the housing 2 can be reduced, and the production cost of the homogenizing module is also reduced.

[0069] In one embodiment, the size of the plane where the light exit hole 3 of the light homogenizing module is located is greater than or equal to the size of the plane where the light entrance hole 4 is located. Figure 3 and Figure 4 As shown, Figure 3 and Figure 4 The size of the plane where the light exit hole 3 of the light homogenizing module is located is larger than the size of the plane where the light entrance hole 4 is located. Figure 5FIG. 4 shows a schematic diagram of the structure of a light homogenization module provided in an embodiment of the present application. Figure 5 As shown, Figure 5 The size of the plane where the light exit hole 3 of the light homogenizing module is located is equal to the size of the plane where the light entrance hole 4 is located. In this case, the superlens 1 can be more easily assembled on the housing 2, thereby effectively reducing the processing difficulty of the light homogenizing module and further reducing the production cost of the light homogenizing module.

[0070] It should be noted that this application Figure 3 and Figure 4 The overall shape of the light homogenizing module shown can be understood as a truncated cone. Figure 5 The overall shape of the light homogenizing module shown can be understood as a cylinder, but this does not mean that the overall shape of the light homogenizing module of the present application is limited to this. The overall shape of the light homogenizing module provided by the present application is not limited as long as it meets the relationship between the dimensions of the plane where the light exit hole and the light entrance hole are located. Figure 6 As shown, Figure 6 FIG. 1 shows a schematic diagram of the structure of a light homogenization module provided in an embodiment of the present application. Figure 6 The size of the plane where the light exit hole 3 of the light homogenizing module is located is greater than the size of the plane where the light entrance hole 4 is located.

[0071] Furthermore, since the function of the light homogenizing module is to diffuse and collimate the light beam, that is, the divergence angle of the light beam passing through the light homogenizing module will become larger, the light output hole 3 of the light homogenizing module only needs to allow all the light beam modulated by the super lens 1 to pass through, and the specific aperture of the light output hole 3 is not limited in this application.

[0072] It should be noted that the light entrance hole 4 is arranged at the bottom of the housing 2. Figures 3 to 6 As shown, in machine vision technology, due to the needs of the application scenario, the light source used is usually a multimode fiber-coupled light source that can output high-power lasers. The multimode fiber-coupled light source outputs a light beam through a fiber connector. Therefore, in this embodiment, a light inlet 4 connected to the fiber connector is provided on the bottom of the housing 2, so that the uniform light module provided in this application can be adapted to the multimode fiber-coupled light source and applied to machine vision technology.

[0073] It should be noted that since the light input hole 4 is used to connect with the optical fiber connector, the optical fiber connector has a protruding structure, and the optical fiber connector is connected to the light homogenizing module by inserting the protruding structure into the light input hole 4, and emits a light beam through the top of the protruding structure. Therefore, in this embodiment, the thickness of the bottom of the light homogenizing module shell 2 should be less than the height of the protruding structure of the optical fiber connector, so that the light beam emitted by the protruding part of the optical fiber connector can be completely emitted and will not be blocked by the light input hole 4, thereby improving the utilization rate of light energy.

[0074] In addition, the light entrance hole 4 can also be equipped with a locking structure (not shown in the figure), which can lock the protruding structure of the optical fiber connector, so that the connection between the optical fiber connector and the light homogenizing module is more stable; similarly, the locking structure of the light entrance hole 4 can be unlocked, thereby realizing easy plugging and unplugging of the light homogenizing module and increasing the flexibility of using the light homogenizing module.

[0075] In one embodiment, the light homogenization module further includes a fixing structure 5, such as Figure 3 , Figure 5 , Figure 6 and Figure 7 As shown, the fixing structure 5 is arranged on the inner surface of the housing 2 , and the fixing structure 5 is used to fix the superlens 1 .

[0076] One side of the fixing structure 5 is used to connect with the inner surface of the housing 2, and the other side is used to connect with the metalens 1, thereby providing a fixing effect for the metalens 1. It should be noted that the specific shape of the fixing structure 5 is not limited, as long as the fixing structure 5 can fix the metalens 1 at the corresponding position.

[0077] The fixing structure 5 may also be a part of the housing 2, that is, the fixing structure 5 is an integral part of the housing 2. As an example, a raised portion is provided on the inner surface of the housing 2, and the raised portion is the fixing structure 5, and the raised portion can be connected to the metalens 1, thereby fixing the metalens 1.

[0078] In one embodiment, the light homogenization module further includes a protective glass 6; the protective glass 6 is disposed at the light exit hole 3 of the housing 2. Figure 7 As shown, Figure 7 The protective glass 6 serves as a barrier between the light homogenizing module and the external environment, which can effectively prevent the metalens 1 disposed inside the light homogenizing module from being damaged and improve the service life of the light homogenizing module.

[0079] It should be noted that the material of the protective glass needs to be transparent in the working band of the light beam emitted by the light source, so that the uniform light beam modulated by the superlens 1 can be transmitted to the target plane.

[0080] The present application also provides a uniform light emission device, which includes: a multimode fiber-coupled light source; and a uniform light module as described in the above embodiment. The multimode fiber-coupled light source is arranged at the light entrance hole of the housing 2, and the multimode fiber-coupled light source is connected to the light entrance hole 4 of the housing 2; the super lens 1 is arranged at the light exit side of the multimode fiber-coupled light source, that is, the super lens 1 is arranged downstream of the multimode fiber-coupled light source along the light path direction.

[0081] like Figure 8 As shown, Figure 8A schematic structural diagram of a uniform light emitting device provided in an embodiment of the present application is shown, wherein the light source 7 is a fiber connector of a multimode fiber-coupled light source, and the protruding structure of the fiber connector is inserted into the light entrance hole 4 at the bottom of the uniform light module housing 2 to achieve connection with the uniform light module, and the emission light 8 is emitted through the protruding structure of the fiber connector. The emission light 8 is modulated by the superlens 1 to obtain a uniform light beam 9, and the uniform light beam 9 forms a homogenized light spot on the target plane A after propagating a certain distance.

[0082] The present application also provides a machine vision system, characterized in that the machine vision system includes: a receiving device; and a uniform light emitting device as described in the above embodiment.

[0083] Specifically, after the homogenized light emitting device in the machine vision system emits a light beam and forms a homogenized light spot at the target plane, the reflected light beam reflected by the homogenized light spot can be received by the detector carried by the receiving device, that is, the detector on the receiving device can sense the homogenized light spot, so that the machine vision system can determine the distance, shape or posture of the target plane based on the homogenized light spot sensed by the detector on the receiving device.

[0084] It should be noted that the machine vision system provided by the present application can be applied to multiple fields, for example, smart home: used for visual recognition of sweeping robots, gesture recognition for various smart appliances; smart manufacturing: used to detect the flatness of goods on the assembly line; smart logistics: used to automatically identify goods and scan codes for storage, etc. That is, the machine vision system provided by the present application can be applied to multiple scenarios, and fast and accurate detection can be achieved through the homogenized light spot with high edge steepness emitted by the homogenized light emitting device and the detector in the receiving device.

[0085] Example 1

[0086] See also Fig. 9 and Fig.10 , Fig. 9 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 1 of the present application is shown. Fig.10 The schematic diagram of the light intensity of the uniform light spot projected by the uniform light emitting device provided in Example 1 of the present application in the x-center section and the y-center section is shown, Fig.10 The horizontal axis is FOI, in degrees, and the vertical axis is normalized light intensity distribution. This embodiment is simulated by MATLAB software. In this embodiment, the light source 7 is a multimode fiber-coupled light source with a wavelength of 808 nm. The FOI of the homogenized light spot projected by this homogenized light emitting device is 75°×75°, that is, the divergence angle half angle of the homogenized light beam in any target direction is 37.5°. Fig.10As shown, in the positive direction of the x-axis of the homogenized light spot, the FOI half-angle corresponding to 90% of the maximum light intensity is 36.3°, and the FOI half-angle corresponding to 10% of the maximum light intensity is 38.2°, that is, the tailing degree of the homogenized light spot in the positive direction of the x-axis is 1.9°; the tailing degrees in the other target directions are similar, all less than 2°, and the uniformity of the homogenized light spot is 80%.

[0087] Example 2

[0088] See also Fig.11 and Fig.12 , Fig.11 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 2 of the present application is shown. Fig.12 The schematic diagram of the light intensity of the uniform light spot projected by the uniform light emitting device provided in Example 2 of the present application in the x-center section and the y-center section is shown, Fig.12 The horizontal axis is FOI, in degrees, and the vertical axis is normalized light intensity distribution. This embodiment is simulated by MATLAB software. In this embodiment, the light source 7 is a multimode fiber-coupled light source with a wavelength of 940nm. The FOI of the homogenized light spot projected by this homogenized light emitting device is 50°×50°, that is, the divergence angle half angle of the homogenized light beam in any target direction is 25°. Fig.12 As shown, in the positive direction of the x-axis of the homogenized light spot, the FOI half-angle corresponding to 90% of the maximum light intensity is 23.8°, and the FOI half-angle corresponding to 10% of the maximum light intensity is 25.1°, that is, the tailing degree of the homogenized light spot in the positive direction of the x-axis is 1.3°; the tailing degrees in the other target directions are similar, all less than 2°, and the uniformity of the homogenized light spot is 80%.

[0089] Example 3

[0090] See also Fig.13 and Fig.14 , Fig.13 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 3 of the present application is shown. Fig.14 The schematic diagram of the light intensity of the uniform light spot projected by the uniform light emitting device provided in Example 3 of the present application in the x-center section and the y-center section is shown, Fig.14 The horizontal axis is FOI, in degrees, and the vertical axis is normalized light intensity distribution. This embodiment is simulated by MATLAB software. In this embodiment, the light source 7 is a multimode fiber-coupled light source with a wavelength of 1550nm. The FOI of the homogenized light spot projected by this homogenized light emitting device is 60°×60°, that is, the divergence angle half angle of the homogenized light beam in any target direction is 30°. Fig.14As shown, in the positive direction of the x-axis of the homogenized light spot, the FOI half-angle corresponding to 90% of the maximum light intensity is 29.7°, and the FOI half-angle corresponding to 10% of the maximum light intensity is 31.5°, that is, the tailing degree of the homogenized light spot in the positive direction of the x-axis is 1.8°; the tailing degrees in the other target directions are similar, all less than 2°, and the uniformity of the homogenized light spot is 80%.

[0091] Example 4

[0092] See also Fig.15 and Fig.16 , Fig.15 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 4 of the present application is shown. Fig.16 The spatial irradiance diagram of the position of the homogenized light spot in the y direction projected by the homogenized light emitting device provided in Example 4 of the present application is shown. Fig.16 The horizontal axis is the coordinate value from the point on the homogenized light spot to the y-axis center of the homogenized light spot, and the horizontal axis is the corresponding positional spatial radiance. This embodiment is simulated by Zemax software. In this embodiment, the light source 7 is a multimode fiber-coupled light source with a wavelength of 808nm, and the superlens 1 is a superlens array. The arrangement period of the sub-superlenses in the superlens array is 0.5mm, the number is 9×9, the overall size of the superlens 1 is 4.5mm×4.5mm, and the distance from the superlens 1 to the target plane is 200mm. The FOI of the homogenized light spot projected by this uniform light emitting device is 30°×30°, that is, the divergence angle half angle of the uniform light beam in any target direction is 15°. According to Fig.16 The coordinate value of and the distance from the metalens 1 to the target plane can be calculated. In the positive direction of the y-axis of the homogenized light spot, the FOI half-angle corresponding to 90% of the maximum light intensity is 14.45°, and the FOI half-angle corresponding to 10% of the maximum light intensity is 15.3°, that is, the tailing degree of the homogenized light spot in the positive direction of the y-axis is 0.85°; the tailing degrees in the other target directions are similar, all less than 1°.

[0093] Example 5

[0094] See also Fig.17 and Fig.18 , Fig.17 A schematic diagram of a homogenized light spot projected by the homogenized light emitting device provided in Example 5 of the present application is shown. Fig.18 The spatial irradiance diagram of the position of the homogenized light spot in the y direction projected by the homogenized light emitting device provided in Example 5 of the present application is shown. Fig.18The horizontal axis is the coordinate value from the point on the homogenized light spot to the y-axis center of the homogenized light spot, and the horizontal axis is the corresponding positional spatial radiance. This embodiment is simulated by Zemax software. In this embodiment, the light source 7 is a multimode fiber-coupled light source with a wavelength of 808nm, and the superlens 1 is a superlens array. The arrangement period of the sub-superlenses in the superlens array is 0.5mm, the number is 9×9, the overall size of the superlens 1 is 4.5mm×4.5mm, and the distance from the superlens 1 to the target plane is 200mm. The FOI of the homogenized light spot projected by this uniform light emitting device is 20°×20°, that is, the divergence angle half angle of the uniform light beam in any target direction is 10°. According to Fig.16 The coordinate value of and the distance from the metalens 1 to the target plane can be calculated. In the positive direction of the y-axis of the homogenized light spot, the FOI half-angle corresponding to 90% of the maximum light intensity is 9.57°, and the FOI half-angle corresponding to 10% of the maximum light intensity is 10.46°, that is, the tailing degree of the homogenized light spot in the positive direction of the y-axis is 0.89°; the tailing degrees in the other target directions are similar, all less than 1°.

[0095] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the utility model disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the appended claims.

Claims

1. A metalens for a robot, characterized in that: The superlens comprises: a substrate and a micro-nano structure arranged on the substrate; the superlens is used to receive the emission light of the multi-mode fiber-coupled light source and modulate the emission light into a uniform light beam, and the uniform light beam forms a uniform light spot on the target plane; Among them, the phase of the superlens includes a homogenization phase and a collimation phase; the homogenization phase is used to homogenize the light intensity distribution of the light beam received by the superlens; the collimation phase is used to collimate the light beam received by the superlens.

2. The metalens according to claim 1, characterized in that When the divergence half angle of the uniform light beam in the target direction is less than or equal to 15°, the tailing degree of the uniform light spot in the target direction is less than 1°.

3. The metalens according to claim 1, characterized in that When the divergence half angle of the uniform light beam in the target direction is less than or equal to 37.5°, the tailing degree of the uniform light spot in the target direction is less than 2°.

4. A light homogenization module for a robot, characterized in that: The light homogenization module comprises: the super lens according to any one of claims 1 to 3; a housing; Wherein, the shell is used to fix the super lens, and a light exit hole and a light entrance hole are provided on the shell; The super lens is arranged inside the space enclosed by the shell.

5. The light homogenization module according to claim 4, characterized in that: The light exit hole and the light entrance hole are arranged on the same optical axis.

6. The light homogenization module according to claim 4, characterized in that: The light homogenization module also includes a fixing structure; The fixing structure is arranged on the inner surface of the shell, and the fixing structure is used to fix the super lens.

7. The light homogenization module according to claim 4, characterized in that: The light homogenization module also includes a protective glass; The protective glass is arranged at the light exit hole of the housing.

8. The light homogenization module according to claim 4, characterized in that: The size of the plane where the light exit hole is located is greater than or equal to the size of the plane where the light entrance hole is located.

9. A uniform light emitting device for a robot, characterized in that: The uniform light emitting device comprises: a multimode fiber-coupled light source; a uniform light module as described in any one of claims 4 to 7; The multimode fiber-coupled light source is arranged at the light entrance hole of the shell, and the super lens is arranged at the light exit side of the multimode fiber-coupled light source.

10. A machine vision system, characterized in that: The machine vision system comprises: a receiving device; and a uniform light emitting device as described in any one of claims 8 to 9.

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