Superlens for optical emission module and optical emission module comprising same

Abstract

The utility model provides a super lens for an optical emission module and the optical emission module comprising the same. The super lens provided by the utility model comprises a substrate and a micro-nano structure, the super lens is used for receiving at least one of the first incident light and the second incident light; wherein the target physical attribute of the first incident light is different from the target physical attribute of the second incident light; the super lens modulates first incident light into a first optical signal by providing first phase distribution; the super lens modulates second incident light into a second optical signal by providing second phase distribution; at least one of the first optical signal and the second optical signal is used for acquiring depth information of the target object. By adopting the super lens provided by the invention, the depth information of the target object can be fully extracted without additionally arranging optical devices except the super lens in the optical emission module, so that the size and the weight of the optical emission module are reduced, and the performance stability of the optical emission module is improved.

Description

Technical Field

[0001] This application relates to the field of optics, and particularly to a metalens for an optical emission module and an optical emission module including the same. Background Art

[0002] In scenarios such as vehicle-mounted and face recognition, it is usually necessary to use an optical emission module to emit an optical signal containing preset optical information to a target object, so that a light spot is projected on the surface of the target object; in this way, the light spot contains both the optical information in the optical signal emitted by the optical emission module and the depth information of the target object; then, an optical reception module is used to receive the optical signal reflected from the surface of the target object, identify the light spot on the surface of the target object, and then combine the optical information in the optical signal emitted by the optical emission module to extract the depth information of the target object, thereby completing three-dimensional sensing of the target object.

[0003] In the related art, in order to more fully extract the depth information of the target object, additional optical devices need to be provided in the optical emission module. The additional optical devices will cause the optical emission module to have a large volume and weight, and will also cause the performance of the optical emission module to be unstable. Summary of the Utility Model

[0004] An object of this application is to provide a metalens for an optical emission module and an optical emission module including the same. By using the metalens provided in this application, it is possible to fully extract the depth information of the target object without additionally providing optical devices other than the metalens in the optical emission module, thereby reducing the volume and weight of the optical emission module and improving the performance stability of the optical emission module.

[0005] According to one aspect of the embodiments of this application, a metalens for an optical emission module is disclosed. The metalens includes a substrate and a micro-nano structure provided on the substrate; the metalens is configured to receive at least one of a first incident light and a second incident light and modulate the received incident light;

[0006] Wherein, a target physical property of the first incident light is different from a target physical property of the second incident light;

[0007] The metalens modulates the first incident light into a first optical signal by providing a first phase distribution; the metalens modulates the second incident light into a second optical signal by providing a second phase distribution; the first phase distribution and the second phase distribution are different from each other and independent of each other;

[0008] At least one of the first optical signal and the second optical signal is used to obtain depth information of a target object; and, a composite optical signal formed by the first optical signal and the second optical signal is used to enhance the depth information.

[0009] In an exemplary embodiment of the present application, the target physical property of the incident light includes: the central wavelength of the light beam; or, the polarization state of the light beam.

[0010] In an exemplary embodiment of the present application, when the target physical property of the incident light includes the polarization state of the light beam, the micro-nano structure is polarization-related.

[0011] In an exemplary embodiment of the present application, the first optical signal is used to project a light spot array, and the second optical signal is used to provide flood illumination;

[0012] The composite optical signal is used to enhance the depth information in a complementary manner of information accuracy and information resolution.

[0013] In an exemplary embodiment of the present application, the first optical signal is used to project a single-line light spot, and the second optical signal is used to provide flood illumination;

[0014] The composite optical signal is used to enhance the depth information in a way of information denoising.

[0015] In an exemplary embodiment of the present application, the second incident light comes from at least two sub-light sources, and the second incident lights from different sub-light sources respectively cover corresponding second sub-superlens regions on the superlens;

[0016] The second sub-superlens regions do not overlap with each other, and, the second phase distribution includes the collimation phases respectively provided by the superlens on the second sub-superlens regions.

[0017] In an exemplary embodiment of the present application, the first optical signal is used to project a light spot array or a single-line light spot, and the second optical signal is used to project a light spot array or a single-line light spot;

[0018] The composite optical signal is used to enhance the depth information in a way of information fusion.

[0019] In an exemplary embodiment of the present application, the target working distance of the light spot projected by the first optical signal is different from the target working distance of the light spot projected by the second optical signal.

[0020] In an exemplary embodiment of the present application, at least part of the light spot regions of the light spot projected by the first optical signal and the light spot projected by the second optical signal do not overlap at the same target working distance.

[0021] According to one aspect of an embodiment of the present application, an optical emission module is disclosed, the optical emission module comprising: a light source; a super lens as provided in any of the above embodiments;

[0022] The light source is used to provide the first incident light and the second incident light to the superlens in a time-sharing manner, or to provide the first incident light and the second incident light to the superlens at the same time.

[0023] In an exemplary embodiment of the present application, the light source includes a first sub-light source for providing the first incident light and a second sub-light source for providing the second incident light; the first sub-light source and the second sub-light source are arranged alternately.

[0024] In an exemplary embodiment of the present application, the target physical property of the incident light includes the central wavelength of the light beam;

[0025] The light source comprises a first sub-light source and a second sub-light source having different central wavelengths, the first sub-light source is used to provide the first incident light, and the second sub-light source is used to provide the second incident light;

[0026] Alternatively, the light source includes a sub-light source with adjustable wavelength to provide the first incident light or the second incident light by adjusting the wavelength.

[0027] In an exemplary embodiment of the present application, the target physical property of the incident light includes the polarization state of the light beam;

[0028] The light source comprises a first sub-light source and a second sub-light source having different polarization states, the first sub-light source is used to provide the first incident light, and the second sub-light source is used to provide the second incident light;

[0029] Alternatively, the light source includes a polarization-adjustable sub-light source to provide the first incident light or the second incident light by adjusting the polarization state;

[0030] Alternatively, the optical emission module further includes a polarizer, which is disposed between the light source and the superlens, and is used to cooperate with the light source to provide the first incident light or the second incident light.

[0031] In an exemplary embodiment of the present application, the first optical signal is used to project a light spot array, and the second optical signal is used to provide flood lighting;

[0032] The light source includes at least two second sub-light sources arranged at intervals for providing the second incident light; the second incident light emitted by each second sub-light source respectively covers a corresponding second sub-superlens area on the superlens, and the second sub-superlens areas do not overlap with each other.

[0033] In an exemplary embodiment of the present application, the second sub-light sources are arranged periodically;

[0034] The light source includes at least two light source units arranged periodically, and each light source unit includes one of the second sub-light sources and at least one first sub-light source for providing the first incident light.

[0035] In an exemplary embodiment of the present application, at least one of the first optical signal and the second optical signal is used to project a crosshair spot;

[0036] The light source includes at least two light source units arranged at intervals, and the emitted light of each light source unit is respectively used to project a crosshair spot; by sequentially lighting the light source units, the crosshair spots obtained by projection perform a scanning action.

[0037] The superlens provided by the present application can optionally receive the first incident light and the second incident light simultaneously, modulate and output the first optical signal and the second optical signal simultaneously; the first optical signal and the second optical signal output simultaneously together constitute a composite optical signal. Compared with a single optical signal, the composite optical signal contains richer optical information; thus, compared with a single optical signal, the composite optical signal can be more fully and effectively combined with the depth information of the target object, enhance the depth information of the target object, and further can more fully extract the depth information of the target object.

[0038] It can be seen from this that the superlens provided by the present application can modulate and output a composite optical signal with two types of optical signals by cooperatively receiving two incident lights; therefore, by using the superlens provided by the present application, there is no need to additionally provide optical devices other than the superlens in the optical emission module, and the depth information of the target object can be fully extracted, thereby reducing the volume and weight of the optical emission module and improving the performance stability of the optical emission module.

[0039] Other features and advantages of the present application will become apparent through the following detailed description, or will be partially learned through the practice of the present application.

[0040] It should be understood that the above general description and the following detailed description are only exemplary and do not limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The above and other objects, features, and advantages of the present application will become more apparent by describing its exemplary embodiments in detail with reference to the accompanying drawings.

[0042] Figure 1 The structure of a metalens in an embodiment of the present application and a schematic diagram of its input and output are shown.

[0043] Figure 2 A schematic diagram of the input and output of a metalens in an embodiment of the present application is shown.

[0044] Figure 3 A schematic diagram of the input and output of a metalens in an embodiment of the present application is shown.

[0045] Figure 4 A schematic diagram of the input and output of a metalens in an embodiment of the present application is shown.

[0046] Figure 5 A schematic diagram of the input and output of a metalens in an embodiment of the present application is shown.

[0047] Figure 6 A schematic diagram of the input and output of a metalens in an embodiment of the present application is shown.

[0048] Figure 7 A schematic diagram of the input and output of a metalens in an embodiment of the present application is shown.

[0049] Figure 8 A schematic diagram of the distribution of the spot projected by the first optical signal and the spot projected by the second optical signal at the same target working distance in an embodiment of the present application is shown.

[0050] Figure 9 A schematic diagram of the distribution of the spot projected by the first optical signal and the spot projected by the second optical signal at the same target working distance in an embodiment of the present application is shown.

[0051] Figure 10 A schematic diagram of the distribution of the spot projected by the first optical signal and the spot projected by the second optical signal at the same target working distance in an embodiment of the present application is shown.

[0052] Figure 11 A schematic diagram of the distribution of the spot projected by the first optical signal and the spot projected by the second optical signal at the same target working distance in an embodiment of the present application is shown.

[0053] Figure 12 A schematic diagram of the distribution of the spot projected by the first optical signal and the spot projected by the second optical signal at the same target working distance in an embodiment of the present application is shown.

[0054] Figure 13 The structural schematic diagram of the optical emission module in an embodiment of the present application is shown.

[0055] Figure 14 The schematic diagram of the arrangement of sub-light sources in the light source in an embodiment of the present application is shown.

[0056] Figure 15 The schematic diagram of the one-dimensional line spot performing a scanning action in an embodiment of the present application is shown.

[0057] Figure 16 The schematic diagram of the one-dimensional line spot performing a scanning action in an embodiment of the present application is shown.

[0058] Figure 17 The schematic diagram of the one-dimensional line spot performing a scanning action in an embodiment of the present application is shown.

[0059] Figure 18 The schematic diagram of the arrangement of sub-light sources in the light source in the optical emission module provided in Embodiment 1 is shown.

[0060] Figure 19 The schematic diagram of the first phase distribution provided by the meta-lens for the first incident light in the optical emission module provided in Embodiment 1 is shown.

[0061] Figure 20 The schematic diagram of the second phase distribution provided by the meta-lens for the second incident light in the optical emission module provided in Embodiment 1 is shown.

[0062] Figure 21 The schematic diagram of the light spot array obtained by projection when the optical emission module provided in Embodiment 1 outputs the first optical signal is shown.

[0063] Figure 22 The schematic diagram of the floodlight illumination provided when the optical emission module provided in Embodiment 1 outputs the second optical signal is shown.

[0064] Figure 23 The target image used when designing the first phase distribution by the GS algorithm in Embodiment 2 is shown.

[0065] Figure 24 The target image used when designing the second phase distribution by the GS algorithm in Embodiment 2 is shown.

[0066] Figure 25 The schematic diagram of the light spot array obtained by projection when the optical emission module provided in Embodiment 2 outputs the first optical signal is shown.

[0067] Figure 26 The schematic diagram of the light spot array obtained by projection when the optical emission module provided in Embodiment 2 outputs the second optical signal is shown.

[0068] Figure 27 Shows a schematic diagram of the light spot array obtained by projection when the optical emission module provided in Embodiment 2 outputs the first optical signal and the second optical signal simultaneously.

[0069] Figure 28 Shows a schematic diagram of the first phase distribution provided by the metalens for the first incident light in the optical emission module provided in Embodiment 3.

[0070] Figure 29 Shows a schematic diagram of the second phase distribution provided by the metalens for the second incident light in the optical emission module provided in Embodiment 3.

[0071] Figure 30 Shows a schematic diagram of the light spot array obtained by projection when the optical emission module provided in Embodiment 3 outputs the first optical signal.

[0072] Figure 31 Shows a schematic diagram of the one-dimensional line light spot obtained by projection when the optical emission module provided in Embodiment 3 outputs the second optical signal.

[0073] Figure 32 Shows a schematic diagram of the first phase distribution provided by the metalens for the first incident light in the optical emission module provided in Embodiment 4.

[0074] Figure 33 Shows a schematic diagram of the second phase distribution provided by the metalens for the second incident light in the optical emission module provided in Embodiment 4.

[0075] Figure 34 Shows a schematic diagram of the one-dimensional line light spot obtained by projection when the optical emission module provided in Embodiment 4 outputs the first optical signal.

[0076] Figure 35 Shows a schematic diagram of the one-dimensional line light spot obtained by projection when the optical emission module provided in Embodiment 4 outputs the second optical signal.

[0077] Figure 36 Shows a schematic diagram of the cross-shaped light spot obtained by projection when the optical emission module provided in Embodiment 4 outputs the first optical signal and the second optical signal simultaneously.

[0078] Description of reference numerals:

[0079] 1 - Metalens; 11 - Substrate; 12 - Micro-nano structure; 2 - Light source; 21 - First sub-light source; 210 - First incident light; 22 - Second sub-light source; 220 - Second incident light; 310 - First optical signal; 320 - Second optical signal. Detailed implementation manners

[0080] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these exemplary embodiments are provided so that this application will be more thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The drawings are merely schematic illustrations of this application and are not necessarily drawn to scale. Like reference numerals in the drawings denote like or similar parts, and thus their repeated description will be omitted.

[0081] In addition, the described features, structures, or characteristics may be combined in any suitable manner in one or more exemplary embodiments. In the following description, numerous specific details are provided to give a thorough understanding of the exemplary embodiments of this application. However, those skilled in the art will recognize that one or more of the specific details may be omitted in practicing the technical solutions of this application, or other methods, components, steps, etc. may be used. In other cases, well-known structures, methods, implementations, or operations are not shown or described in detail to avoid obscuring aspects of this application.

[0082] Some of the block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0083] The optical emission modules provided in the related art are generally designed for target objects in an ideal environment. However, in many application scenarios, the environment where the target object is located is usually variable and not fixed (for example: in a face recognition application, the target object is the user holding the electronic device where the optical emission module is located; the user may be in a bright environment with sufficient light or in a dim environment with poor light); therefore, in many application scenarios, the target object is not always in an ideal environment.

[0084] When the target object is in a non-ideal environment, for the optical emission module designed for the target object in an ideal environment, the optical information in the optical signal it emits often cannot be fully and effectively combined with the depth information of the target object, and thus the light spot projected by the optical signal it emits on the surface of the target object cannot be fully used to extract the depth information of the target object, resulting in the inability to perform high-quality three-dimensional sensing on the target object.

[0085] In order to more fully extract the depth information of the target object, related technologies propose to additionally provide an optical device in the optical emission module designed for the target object in an ideal environment. The additionally provided optical device is used to provide an additional optical signal for the target object in a non-ideal environment, thereby improving the quality of three-dimensional sensing. In this way, by additionally providing an optical device, regardless of whether the target object is in an ideal environment or a non-ideal environment, the optical emission module provided by related technologies can perform three-dimensional sensing on the target object with high quality.

[0086] However, due to the need to additionally provide an optical device, the optical emission module provided by related technologies has a relatively large volume and weight.

[0087] Moreover, the additionally provided optical device and the original optical device in the optical emission module are usually physically separated from each other. In this way, it is necessary to precisely control the relative position between the two to ensure that they can cooperate with each other according to the design expectation. Once the assembly error is too large, the actual performance of the optical emission module will deviate significantly from the design expectation, resulting in unstable performance of the optical emission module.

[0088] In summary, for the optical emission module provided by related technologies, in order to more fully extract the depth information of the target object, it is necessary to additionally provide an optical device. The additionally provided optical device will cause the optical emission module to have a relatively large volume and weight, and will also cause the performance of the optical emission module to be unstable.

[0089] In consideration of overcoming the above-mentioned defects existing in related technologies, the present application provides a metalens for an optical emission module. By using the metalens provided by the present application, it is possible to fully extract the depth information of the target object without additionally providing optical devices other than the metalens in the optical emission module, thereby reducing the volume and weight of the optical emission module and improving the performance stability of the optical emission module.

[0090] Figure 1 The structure of the metalens in an embodiment of the present application and a schematic diagram of its input and output are shown. Refer to Figure 1 , the metalens 1 provided by the present application includes a substrate 11 and a micro-nano structure 12 provided on the substrate 11. The metalens 1 mainly provides a phase mutation to the received light beam through the micro-nano structures 12 at various positions, so that a certain phase gradient is generated at various positions on the metalens 1, and then a certain modulation effect is applied to the light beams received at various positions.

[0091] In the embodiment of the present application, the metalens 1 is used to receive at least one of the first incident light 210 and the second incident light 220, and modulate the received incident light.

[0092] That is, the metalens 1 can only receive the first incident light 210 and modulate the first incident light 210; the metalens 1 can also only receive the second incident light 220 and modulate the second incident light 220; the metalens 1 can also receive the first incident light 210 and the second incident light 220 simultaneously, and modulate the first incident light 210 while also modulating the second incident light 220.

[0093] Among them, the target physical property of the first incident light 210 is different from the target physical property of the second incident light 220.

[0094] It should be noted that the phase mutation provided by the micro-nano structure 12 for the light beam is closely related to the physical property of the light beam. The same micro-nano structure 12 can provide different phase mutations for light beams with different physical properties. Therefore, in the embodiments of the present application, by reasonably screening the micro-nano structures 12 at various positions, the metalens 1 provides a first phase distribution for the first incident light 210 and a second phase distribution for the second incident light 220. The first phase distribution provided by the metalens 1 refers to the set of phase mutations provided by the micro-nano structures 12 at various positions for the first incident light 210; similarly, the second phase distribution provided by the metalens 2 refers to the set of phase mutations provided by the micro-nano structures 12 at various positions for the second incident light 220.

[0095] In the embodiments of the present application, the first phase distribution and the second phase distribution are different from each other and independent of each other. Under the action of the first phase distribution, the first incident light 210 is modulated by the metalens 1 into a first optical signal 310 and output by the metalens 1; under the action of the second phase distribution, the second incident light 220 is modulated by the metalens 1 into a second optical signal 320 and output by the metalens 1.

[0096] At least one of the first optical signal 310 and the second optical signal 320 is used to obtain the depth information of the target object. That is, in an ideal or relatively simple environment, only using a certain optical signal among the first optical signal 310 and the second optical signal 320 can fully extract the depth information of the target object, and then the three-dimensional sensing of the target object can be completed with high quality.

[0097] However, as mentioned above, in many scenarios where three-dimensional sensing is applied, the environment in which the target object is located is usually changeable and not fixed. Therefore, in a less than ideal or more complex environment, only using one of the first optical signal 310 and the second optical signal 320 cannot fully extract the depth information of the target object. In this case, the metalens 1 provided in the present application can choose to simultaneously receive the first incident light 210 and the second incident light 220, and simultaneously modulate and output the first optical signal 310 and the second optical signal 320; the first optical signal 310 and the second optical signal 320 outputted simultaneously together constitute a composite optical signal.

[0098] Compared with a single optical signal, a composite optical signal contains richer optical information; therefore, compared with a single optical signal, the composite optical signal can be more fully and effectively combined with the depth information of the target object, enhance the depth information of the target object, and then more fully extract the depth information of the target object.

[0099] It can be seen that the superlens 1 provided in the present application can modulate and output a composite optical signal having two types of optical signals by receiving two types of incident light; therefore, by using the superlens 1 provided in the present application, there is no need to set up additional optical devices other than the superlens in the optical emission module, and the depth information of the target object can be fully extracted, thereby reducing the volume and weight of the optical emission module and improving the performance stability of the optical emission module.

[0100] Furthermore, since the target physical properties of the first incident light 210 are different from the target physical properties of the second incident light 220, even if the first incident light 210 and the second incident light 220 overlap, there will be no crosstalk between the first incident light 210 and the second incident light 220. That is, the first incident light 210 and the second incident light 220 can overlap with each other and be incident on the superlens 1 without crosstalk; therefore, in this case, the effective area of ​​the superlens 1 used to modulate the first incident light 210 and the effective area used to modulate the second incident light 220 can overlap with each other, thereby reducing the effective area of ​​the superlens 1. The smaller the effective area of ​​the superlens 1, the smaller the cost of the superlens 1. Therefore, the superlens 1 provided in the present application can also reduce the cost of the superlens 1, thereby reducing the cost of the optical emission module. Among them, the effective area of ​​the superlens 1 refers to the area in the superlens 1 where the light beam is effectively modulated by the micro-nano structure 12.

[0101] It should be noted that although Figure 1 The super lens 1 shown is provided with only one layer of micro-nano structure 12 on its light emitting surface, and, Figure 1The micro-nano structure 12 shown is a positive micro-nano structure, but this does not mean that the superlens 1 provided in this application can only adopt this structural configuration. Specifically, the superlens 1 provided in this application can be provided with any number of layers of micro-nano structures 12 on either the light incident surface or the light output surface, and each layer of micro-nano structure 12 can be a positive micro-nano structure or a negative micro-nano structure.

[0102] It should also be noted that Figure 1 The first optical signal 310 and the second optical signal 320 shown are only abstractly shown in the form of symbols to indicate that they are different, Figure 1 and the specific symbol styles shown do not represent the specific physical parameters of the corresponding optical signals.

[0103] In one embodiment, the target physical properties of the incident light include: the central wavelength of the light beam.

[0104] Specifically, in this embodiment, the central wavelength of the first incident light 210 is different from that of the second incident light 220. The micro-nano structure 12 in the superlens 1 can provide different phase mutations for light beams with different central wavelengths. Therefore, the first phase distribution provided by the superlens 1 for the first incident light 210 is different from and independent of the second phase distribution provided by the superlens 1 for the second incident light 220.

[0105] In this embodiment, in the design stage, the micro-nano structures 12 to be arranged at each position on the superlens 1 can be determined in the following manner:

[0106] According to the central wavelength of the first incident light 210, the optical characteristics of the first incident light 210 (such as: divergence angle, light intensity distribution, etc.) and the optical characteristics of the first optical signal 310 (such as: divergence angle, light intensity distribution, etc.), determine the first phase distribution that the superlens 1 should provide for the first incident light 210, so as to determine the first phase mutation that the micro-nano structures 12 at each position on the superlens 1 should provide for the light beam with the first central wavelength. Similarly, determine the second phase mutation that the micro-nano structures 12 at each position on the superlens 1 should provide for the light beam with the second central wavelength.

[0107] Therefore, for each position on the superlens 1, determine the corresponding phase mutation combination (the first phase mutation and the second phase mutation) at that position, then screen out the micro-nano structures 12 that can provide the corresponding phase mutation combination from the micro-nano structure database, and arrange the screened micro-nano structures 12 at that position. In this way, the micro-nano structures 12 to be arranged at each position on the superlens 1 are determined. Among them, the micro-nano structure database refers to a database for recording the phase mutations provided by micro-nano structures 12 with various structural parameters for light beams with various physical properties.

[0108] In one embodiment, the target physical properties of the incident light include: the polarization state of the light beam.

[0109] Specifically, in this embodiment, the polarization state of the first incident light 210 is different from that of the second incident light 220. The micro-nano structures 12 in the metalens 1 can provide different phase mutations for light beams with different polarization states. Thus, the first phase distribution provided by the metalens 1 for the first incident light 210 is different from and independent of the second phase distribution provided by the metalens 1 for the second incident light 220.

[0110] In this embodiment, in the design stage, the micro-nano structures 12 to be arranged at each position on the metalens 1 can be determined in the following manner:

[0111] According to the polarization state of the first incident light 210, the optical characteristics of the first incident light 210 (such as: divergence angle, light intensity distribution, etc.) and the optical characteristics of the first optical signal 310 (such as: divergence angle, light intensity distribution, etc.), determine the first phase distribution that the metalens 1 should provide for the first incident light 210, so as to determine the first phase mutation that the micro-nano structures 12 at each position on the metalens 1 should provide for the light beam with the first polarization state. Similarly, determine the second phase mutation that the micro-nano structures 12 at each position on the metalens 1 should provide for the light beam with the second polarization state.

[0112] Then, for each position on the metalens 1, determine the corresponding phase mutation combination (the first phase mutation and the second phase mutation) at that position, and then select the micro-nano structures 12 from the micro-nano structure database that can provide the corresponding phase mutation combination, and arrange the selected micro-nano structures 12 at that position. In this way, the micro-nano structures 12 to be arranged at each position on the metalens 1 are determined. Among them, the micro-nano structure database records the phase mutations provided by the micro-nano structures 12 with various structural parameters for light beams with various physical properties.

[0113] In one embodiment, when the target physical property of the incident light includes the polarization state of the light beam, the micro-nano structures 12 in the metalens 1 are polarization-related.

[0114] Among them, the micro-nano structures 12 being polarization-related can also be called the micro-nano structures 12 being polarization-sensitive. Polarization-related micro-nano structures refer to micro-nano structures whose optical characteristics depend on the polarization state of the incident light; that is, for incident light with different polarization states, polarization-related micro-nano structures can have different optical characteristics. Specifically, polarization-related micro-nano structures can be obtained by configuring the cross-sectional geometric shape of the micro-nano structures (such as: a rectangle with unequal length and width; an ellipse), the characteristic size (such as: width; height), and the arrangement method (such as: rhombic lattice arrangement; rectangular lattice arrangement).

[0115] In one embodiment, the target physical properties of the incident light include: the central wavelength of the light beam and the polarization state of the light beam.

[0116] Specifically, in this embodiment, the central wavelength of the first incident light 210 is different from that of the second incident light 220, and the polarization state of the first incident light 210 is different from that of the second incident light 220. By providing different phase mutations for light beams with different central wavelengths and different polarization states through the micro-nano structure 12, the first phase distribution provided by the metalens 1 for the first incident light 210 is different from and independent of the second phase distribution provided by the metalens 1 for the second incident light 220.

[0117] Figure 2 The schematic diagram of the input and output of the metalens 1 in an embodiment of the present application is shown. Refer to Figure 2 In one embodiment, the first optical signal 310 output by modulating the first incident light 210 by the metalens 1 is used to project a light spot array, and the second optical signal 320 output by modulating the second incident light 220 is used to provide flood illumination.

[0118] For the light spot array projected by the first optical signal 310, the TOF (Time Of Flight) technology or the structured light technology can be applied to obtain the depth information of the target object. Specifically, when applying the TOF technology, the depth information of the target object can be obtained according to the time taken for each point light spot in the light spot array from emission to reception; when applying the structured light technology, the depth information of the target object can be obtained according to the displacement or deformation of each point light spot in the light spot array.

[0119] When the second optical signal 320 is used to provide flood illumination, the projected floodlight spot is a large-area continuously distributed floodlight spot; preferably, the light intensity of the floodlight spot projected by the second optical signal 320 is evenly distributed.

[0120] It should be noted that the optical information contained in the light spot array has high information accuracy, but the information resolution is not very high. On the contrary, for the optical information contained in the floodlight spot, although its information accuracy is low, its information resolution is very high.

[0121] Therefore, in this embodiment, if the three-dimensional sensing mainly has high requirements for information accuracy, only the first incident light 210 can be provided to the metalens 1, so that the metalens 1 only outputs the first optical signal 310 and only projects a light spot array with high information accuracy.

[0122] If the three-dimensional sensing mainly has high requirements for information resolution, only the second incident light 220 can be provided to the metalens 1, so that the metalens 1 only outputs the second optical signal 320 and only projects a floodlight spot with high information resolution.

[0123] If three-dimensional sensing has high requirements for both information accuracy and information resolution, the first incident light 210 and the second incident light 220 can be provided to the metalens 1 simultaneously, so that the metalens 1 outputs a composite optical signal composed of the first optical signal 310 and the second optical signal 320. On the one hand, the first optical signal 310 in the composite optical signal can complement the information accuracy of the floodlight spot projected by the second optical signal 320 through the projection light spot array; on the other hand, the floodlight spot can complement the information resolution of the light spot array. In this way, the composite optical signal can be used to obtain the depth information of the target object with high information accuracy and high information resolution, thereby enhancing the depth information of the target object in a complementary manner of information accuracy and information resolution.

[0124] It should be noted that in the embodiments of the present application, "accuracy" and "resolution" are two different concepts that are juxtaposed. Among them, "accuracy" describes the deviation degree between a single discrete information and the corresponding true information - the higher the accuracy of a certain type of information, the smaller the deviation between each discrete information and the corresponding true information; conversely, the lower the accuracy of a certain type of information, the larger the deviation between each discrete information and the corresponding true information. "Resolution" describes the minimum scale that can be distinguished when the target object is distinguished according to the obtained information - the higher the resolution of a certain type of information, the smaller the minimum scale that can be distinguished when the target object is distinguished according to this type of information; conversely, the lower the resolution of a certain type of information, the larger the minimum scale that can be distinguished when the target object is distinguished according to this type of information. Information accuracy and information resolution jointly determine information quality; if you want to fully improve information quality, it is best to improve both information accuracy and information resolution at the same time.

[0125] In one embodiment, when the first optical signal 310 is used to project the light spot array, the first phase distribution provided by the metalens 1 for the first incident light 210 can be provided with only a set of collimation phases by the whole metalens 1. In this case, the number of point light spots in the light spot array projected by the first optical signal 310 is equal to the number of sub-light sources that emit the first incident light 210. Therefore, in this case, the light spot array projected by the first optical signal 310 has a relatively large light energy for a single point light spot and a relatively sparse overall point light spot, which is suitable for three-dimensional sensing with low resolution at a long distance.

[0126] The first phase distribution may also include a diffractive replication phase. In this case, the number of point light spots in the light spot array obtained by projecting the first optical signal 310 is generally at least twice the number of sub-light sources emitting the first incident light 210. Thus, in this case, for the light spot array obtained by projecting the first optical signal 310, the light energy of a single point light spot is small, and the overall point light spots are relatively dense, which is suitable for three-dimensional sensing with high resolution at a short distance.

[0127] Regardless of whether the first phase distribution provided by the metalens 1 for the first incident light 210 only includes a collimation phase or includes a diffractive replication phase, when designing the first phase distribution, all sub-light sources emitting the first incident light 210 are preferentially treated as a whole; correspondingly, the metalens 1 as a whole provides a set of first phase distributions.

[0128] Figure 3 FIG. shows a schematic diagram of the input and output of the metalens 1 in an embodiment of the present application. Refer to Figure 3 In one embodiment, the first optical signal 310 output by modulating the first incident light 210 by the metalens 1 is used to project a one-dimensional line light spot, and the second optical signal 320 output by modulating the second incident light 220 is used to provide flood illumination.

[0129] Similar to the light spot array, the one-dimensional line light spot can also apply the TOF technology or the structured light technology to obtain the depth information of the target object. However, since the coverage area of the one-dimensional line light spot is continuous, the one-dimensional line light spot does not have the problem of low information resolution like the light spot array.

[0130] In this embodiment, by simultaneously providing the first incident light 210 and the second incident light 220 to the metalens 1, the metalens 1 can output a composite optical signal composed of the first optical signal 310 and the second optical signal 320. In this case, when there is an overlap between the one-dimensional line light spot obtained by projecting the first optical signal 310 and the flood light spot obtained by projecting the second optical signal 320, image difference can be performed on the overlapping area, and then the information noise in the overlapping area can be removed based on the difference result, so that the depth information of the target object can be more fully extracted; in this way, the composite optical signal enhances the depth information of the target object in the way of information denoising.

[0131] In one embodiment, when the first optical signal 310 is used to project a light spot array or a one-dimensional line light spot, and the second optical signal 320 is used to provide flood illumination, the second phase distribution provided by the metalens 1 for the second incident light 220 may only include a collimation phase for collimation.

[0132] Moreover, in this embodiment, the second incident light 220 is derived from at least two sub-light sources. The second incident light 220 from different sub-light sources respectively covers corresponding second sub-superlens regions on the superlens 1. In this case, the second sub-superlens regions do not overlap with each other; that is, when the second incident light 220 from different sub-light sources irradiates on the superlens 1, there is no crosstalk. Moreover, the collimation phase in the second phase distribution is provided respectively on the second sub-superlens regions.

[0133] It can be understood that if there is crosstalk when the second incident light 220 from different sub-light sources irradiates on the superlens 1, the crosstalk region will receive the second incident light 220 from multiple sources, and the collimation phase on the crosstalk region can collimate at most one source of the second incident light 220 to achieve the expected effect. Therefore, the generation of crosstalk will lead to poor collimation effect, and further make it difficult to effectively improve the floodlighting quality of the second optical signal 320.

[0134] Therefore, in this embodiment, by controlling that there is no crosstalk when the second incident light 220 from different sub-light sources irradiates on the superlens 1, the second incident light 220 from each source can be perfectly collimated by the collimation phase provided by the corresponding second sub-superlens region, thereby effectively improving the floodlighting quality of the second optical signal 320.

[0135] In one embodiment, when the first optical signal 310 is used to project a light spot array or a one-dimensional line light spot, and the second optical signal 320 is used to provide floodlighting, the second phase distribution provided by the superlens 1 for the second incident light 220 includes, in addition to the collimation phase for collimation, a shaping phase for modulating the light intensity distribution.

[0136] When the second optical signal 320 is used to provide floodlighting and the second phase distribution only includes the collimation phase, the light intensity distribution of the second optical signal 320 is basically the same as the light intensity distribution of the second incident light 220. If the light intensity distribution of the second incident light 220 is uneven (for example: the light intensity of the second incident light 220 is Gaussian distributed), and at the same time there are high requirements for the uniformity of the light intensity in floodlighting, then the second phase distribution only including the collimation phase is difficult to meet the requirements.

[0137] Thus, in this case, the second phase distribution further includes a shaping phase so that the second optical signal 320 can provide floodlighting that meets the specific light intensity distribution requirements.

[0138] Figure 4 FIG. shows a schematic diagram of the input and output of the superlens 1 in an embodiment of the present application. Figure 5 FIG. shows a schematic diagram of the input and output of the superlens 1 in an embodiment of the present application. Figure 6Shows a schematic diagram of the input and output of the metalens 1 in an embodiment of the present application. Figure 7 Shows a schematic diagram of the input and output of the metalens 1 in an embodiment of the present application.

[0139] See Figures 4 to 7 , in an embodiment, the first optical signal 310 output by modulating the first incident light 210 by the metalens 1 is used to project a dot matrix or a single-line light spot, and the second optical signal 320 output by modulating the second incident light 220 is also used to project a dot matrix or a single-line light spot.

[0140] Specifically, as Figure 4 shown, both the first optical signal 310 and the second optical signal 320 are used to project a dot matrix; as Figure 5 shown, the first optical signal 310 is used to project a dot matrix, and the second optical signal 320 is used to project a single-line light spot; as Figure 6 shown, the first optical signal 310 is used to project a single-line light spot, and the second optical signal 320 is used to project a dot matrix; as Figure 7 shown, both the first optical signal 310 and the second optical signal 320 are used to project a single-line light spot.

[0141] As mentioned above, the dot matrix obtained by projecting the optical signal can apply TOF technology or structured light technology to obtain the depth information of the target object. Similarly, the single-line light spot obtained by projecting the optical signal can also apply TOF technology or structured light technology to obtain the depth information of the target object.

[0142] In this embodiment, for a relatively ideal environment or an environment with a relatively simple structure, any one of the first optical signal 310 and the second optical signal 320 can be used alone to obtain the depth information of the target object.

[0143] For a non-ideal environment or an environment with a relatively complex structure, a composite optical signal composed of the first optical signal 310 and the second optical signal 320 can be selected for output. The optical information contained in each of the two types of optical signals in the composite optical signal can be used to extract a part of the depth information of the surface of the target object respectively; the depth information of different parts of the surface of the target object can be fused. In this way, the composite optical information can enhance the depth information of the target object in the way of information fusion, so as to obtain the depth information of the target object more fully.

[0144] It should be noted that the single-line light spot obtained by projecting the optical signal can be a single single-line light spot or a single-line light spot array including multiple single-line light spots.

[0145] In one embodiment, when the composite optical signal is used to enhance the depth information of the target object in a way of information fusion, the target working distance of the light spot projected by the first optical signal 310 is different from that of the light spot projected by the second optical signal 320.

[0146] That is, in this embodiment, by configuring different target working distances for the first optical signal 310 and the second optical signal 320 respectively, the composite optical signal is used to enhance the depth information of the target object in a way of information fusion. Among them, the target working distance of the optical signal refers to the distance between the target plane for the optical signal to project the light spot and the metalens 1.

[0147] Specifically, when the target working distance is small, the light energy loss of the light spot projected by the optical signal is small; therefore, in this case, the number and density of the light spots projected by the optical signal can be increased, so as to obtain the depth information of the target object at a short distance with high resolution. However, in this case, when the spatial range occupied by the target object is large (for example, the target object is various obstacles around the vehicle), the depth information with high resolution usually only covers a partial area of the target object.

[0148] On the contrary, when the target working distance is large, the depth information of the target object can be obtained at a long distance and can approximately cover the entire area of the target object; however, in this case, the light energy loss of the light spot projected by the optical signal is large, so it is necessary to reduce the number and density of the light spots projected by the optical signal, thereby reducing the resolution of the depth information of the target object.

[0149] Therefore, by fusing the depth information with high resolution of the partial area of the target object and the depth information with low resolution of the entire area, the depth information of the target object can be obtained more fully.

[0150] It should be noted that in this embodiment, when both the first optical signal 310 and the second optical signal 320 are used to project a light spot array, the target working distance of the light spot array from one source is less than that of the light spot array from the other source; when both the first optical signal 310 and the second optical signal 320 are used to project a one-dimensional line light spot, the target working distance of the one-dimensional line light spot from one source is less than that of the one-dimensional line light spot from the other source; when one of the first optical signal 310 and the second optical signal 320 is used to project a light spot array and the other is used to project a one-dimensional line light spot, it can be that the target working distance of the light spot array is less than that of the one-dimensional line light spot, or the target working distance of the one-dimensional line light spot is less than that of the light spot array.

[0151] Figure 8Shows a schematic diagram of the distribution of the light spot projected by the first optical signal 310 and the light spot projected by the second optical signal 320 in an embodiment of the present application at the same target working distance. Figure 9 Shows a schematic diagram of the distribution of the light spot projected by the first optical signal 310 and the light spot projected by the second optical signal 320 in an embodiment of the present application at the same target working distance. Figure 10 Shows a schematic diagram of the distribution of the light spot projected by the first optical signal 310 and the light spot projected by the second optical signal 320 in an embodiment of the present application at the same target working distance. Figure 11 Shows a schematic diagram of the distribution of the light spot projected by the first optical signal 310 and the light spot projected by the second optical signal 320 in an embodiment of the present application at the same target working distance. Figure 12 Shows a schematic diagram of the distribution of the light spot projected by the first optical signal 310 and the light spot projected by the second optical signal 320 in an embodiment of the present application at the same target working distance.

[0152] See Figures 8 to 12 , in an embodiment, when the composite optical signal is used to enhance the depth information of the target object in a way of information fusion, at least part of the light spot regions of the light spot projected by the first optical signal 310 and the light spot projected by the second optical signal 320 do not overlap at the same target working distance.

[0153] That is, in this embodiment, by configuring the same target working distance for the first optical signal 310 and the second optical signal 320, and controlling at least part of the light spot regions of the light spots projected by the two not to overlap, the composite optical signal is used to enhance the depth information of the target object in a way of information fusion.

[0154] It can be understood that two types of light spots with at least part of the light spot regions not overlapping respectively cover different regions of the target object and can be used to obtain the depth information of different regions of the target object respectively; thus, by controlling at least part of the light spot regions of the light spot projected by the first optical signal 310 and the light spot projected by the second optical signal 320 not to overlap at the same target working distance, the depth information of different regions of the target object can be fused, and then the depth information of the target object can be obtained more fully.

[0155] Specifically, as Figure 8 shown, when both the first optical signal 310 and the second optical signal 320 are used to project a light spot array, each point light spot in the light spot array projected by one of the optical signals is located in the blank region of the light spot array projected by the other optical signal. It should be noted that Figure 8The differences in the light spot shapes shown are only used to distinguish the light spots from different optical signals and are not used to represent the actual shapes of the light spots.

[0156] like Figure 9 As shown, when the first optical signal 310 is used to project a light spot array and the second optical signal 320 is used to project a word line light spot, the word line light spot is located in a blank area of ​​the light spot array. Similarly, the situation when the first optical signal 310 is used to project a word line light spot and the second optical signal 320 is used to project a light spot array is not repeated.

[0157] like Figure 10 as well as Figure 11 As shown, when the first optical signal 310 and the second optical signal 320 are both used to project a line light spot, the line light spots projected by the two types of optical signals do not cross each other and can be parallel, perpendicular, or inclined to each other.

[0158] like Figure 12 As shown, when the first optical signal 310 and the second optical signal 320 are both used to project a word line light spot, the word line light spots projected by the two types of optical signals intersect each other. When the word line light spots projected by the two types of optical signals intersect each other and are perpendicular to each other, the composite optical signal projects Figure 12 The cross-line spot shown; when the two types of optical signals respectively project the straight-line spots that intersect and are inclined to each other, the composite optical signal can project an X-shaped line spot.

[0159] In one embodiment, when at least one of the first optical signal 310 and the second optical signal 320 modulated and output by the metalens 1 is used to project a light spot array, a displacement device is provided for the light source 2 or the metalens 1. Under the action of the displacement device, the metalens 1 is controlled to be displaced relative to the light source 2 in the two-dimensional plane where it is located, so that the light spot array projected by the metalens 1 is displaced on the surface of the target object, thereby expanding the detection area of ​​the light spot array.

[0160] The present application also provides an optical emission module. Figure 13 FIG. 2 shows a schematic diagram of the structure of an optical emission module in an embodiment of the present application. Figure 13 The optical emission module provided in the present application includes: a light source 2; and a superlens 1 as provided in any of the above embodiments.

[0161] The light source 2 is used to provide the first incident light 210 and the second incident light 220 to the metalens 1 in a time-sharing manner. In this case, when the metalens 1 receives the first incident light 210, the second incident light 220 will not be received; when the metalens 1 receives the second incident light 220, the first incident light 210 will not be received.

[0162] Alternatively, the light source 2 is configured to simultaneously provide the first incident light 210 and the second incident light 220 to the metalens 1. In this case, the metalens 1 receives the first incident light 210 and the second incident light 220 simultaneously.

[0163] Whether the light source 2 provides the first incident light 210 and the second incident light 220 in a time-division manner or simultaneously mainly depends on the actual situation and requirements in the application scenario. For example: If both the first optical signal 310 and the second optical signal 320 are used to project a light spot array and the environment where the target object is located is relatively ideal, then preferably, the light source 2 provides the first incident light 210 and the second incident light 220 in a time-division manner; if the first optical signal 310 is used to project a light spot array and the second optical signal 320 is used to provide flood illumination, and the target object is in a dim environment, then preferably, the light source 2 provides the first incident light 210 and the second incident light 220 simultaneously.

[0164] Figure 14 The schematic diagram of the arrangement of the sub-light sources in the light source 2 in an embodiment of the present application is shown. Refer to Figure 14 , in an embodiment, the light source 2 includes a first sub-light source 21 for providing the first incident light 210 and a second sub-light source 22 for providing the second incident light 220, and the first sub-light source 21 and the second sub-light source 22 are arranged in an interleaved manner.

[0165] Compared with the non-interleaved side-by-side arrangement of the first sub-light source 21 and the second sub-light source 22, the interleaved arrangement of the first sub-light source 21 and the second sub-light source 22 can effectively reduce the size of the light-emitting area of the light source 2, thereby improving the integration degree of the light source 2.

[0166] Moreover, the size of the light-emitting area of the light source 2 usually directly affects the size of the effective area of the metalens 1. The larger the size of the light-emitting area of the light source 2, the larger the size of the effective area of the metalens 1, which in turn leads to a higher cost of the metalens 1. Therefore, the interleaved arrangement of the first sub-light source 21 and the second sub-light source 22 can also reduce the cost of the metalens 1, and thus reduce the cost of the optical emission module.

[0167] In an embodiment, the target physical property of the incident light includes the central wavelength of the light beam.

[0168] In this embodiment, the light source 2 includes a first sub-light source 21 and a second sub-light source 22 with different central wavelengths; the first sub-light source 21 is configured to provide the first incident light 210 with a first central wavelength, and the second sub-light source 22 is configured to provide the second incident light 220 with a second central wavelength.

[0169] Alternatively, the light source 2 includes sub-light sources with adjustable wavelengths; each sub-light source can provide the first incident light 210 or the second incident light 220 by adjusting the wavelength. For example, the light source 2 is provided with M rows of sub-light sources, and the wavelength of each sub-light source is adjustable. M is an integer greater than 1. In this case, by adjusting the wavelength, it is possible that the sub-light sources in odd rows all provide the first incident light 210, and the sub-light sources in even rows all provide the second incident light 220; it is also possible that the sub-light sources in even rows all provide the first incident light 210, and the sub-light sources in odd rows all provide the second incident light 220; it is also possible that all sub-light sources provide the first incident light 210; it is also possible that all sub-light sources provide the second incident light 220.

[0170] In one embodiment, the target physical property of the incident light includes the polarization state of the light beam.

[0171] In this embodiment, the light source 2 includes a first sub-light source 21 and a second sub-light source 22 with different polarization states; the first sub-light source 21 is used to provide the first incident light 210 with the first polarization state, and the second sub-light source 22 is used to provide the second incident light 220 with the second polarization state.

[0172] Alternatively, the light source 2 includes sub-light sources with adjustable polarization; each sub-light source can provide the first incident light 210 or the second incident light 220 by adjusting the polarization state.

[0173] Alternatively, the optical emission module further includes a polarizer. The polarizer is arranged between the light source 2 and the metalens 1. In this way, the light beam emitted by the sub-light source in the light source 2 first propagates to the polarizer, and its polarization state is converted by the polarizer into a specific polarization state to form the first incident light 210 or the second incident light 220, and then propagates to the metalens 1.

[0174] In one embodiment, the first optical signal 310 is used to project a light spot array, and the second optical signal 320 is used to provide floodlighting.

[0175] In this embodiment, the light source 2 includes at least two second sub-light sources 22 arranged at intervals for providing the second incident light 220. The second incident light 220 emitted by each second sub-light source 22 respectively covers the corresponding second sub-metalens region on the metalens 1, and the second sub-metalens regions do not overlap with each other. In this way, when the second incident light 220 from different second sub-light sources 22 irradiates on the metalens 1, there is no crosstalk.

[0176] In this case, when the second phase distribution includes the collimation phases respectively provided by the superlens 1 on the second sub-superlens regions, by controlling the non-interference of the second incident lights 220 from different sub-light sources when irradiating on the superlens 1, the second incident lights 220 from each source can be perfectly collimated by the collimation phases provided by the corresponding second sub-superlens regions, thereby effectively improving the flood illumination quality of the second optical signal 320.

[0177] Furthermore, in an embodiment, the second sub-light sources 22 are arranged periodically, so the second sub-superlens regions are arranged at equal intervals and do not overlap. In this case, the light source 2 can be divided into at least two periodically arranged light source units. Each light source unit includes a second sub-light source 22 and at least one first sub-light source 21 for providing the first incident light 210; that is, each light source unit can include a second sub-light source 22 and a first sub-light source 21, or can include a second sub-light source 22 and multiple first sub-light sources 21.

[0178] Since the first optical signal 310 is used to project a light spot array, when each light source unit includes multiple first sub-light sources 21, it is beneficial to increase the number and density of the point light spots in the light spot array under the condition of a fixed target working distance, or to increase the target working distance under the conditions of a fixed number and density of the point light spots in the light spot array.

[0179] In an embodiment, at least one of the first optical signal 310 and the second optical signal 320 is used to project a one-dimensional line light spot. For example: both the first optical signal 310 and the second optical signal 320 are used to project one-dimensional line light spots; or, the first optical signal 310 is used to project a one-dimensional line light spot, and the second optical signal 320 is used to project a light spot array; or, the first optical signal 310 is used to project a light spot array, and the second optical signal is used to project a one-dimensional line light spot.

[0180] In this embodiment, the light source 2 includes at least two light source units arranged at intervals. The emitted light of each light source unit is respectively used to project a one-dimensional line light spot. By sequentially lighting the light source units, the light source units project the corresponding one-dimensional line light spots in sequence according to the lighting order. It can be understood that when the one-dimensional line light spots projected by different light source units are located at different positions, the one-dimensional line light spots obtained by sequential projection can jointly perform a scanning action, thereby obtaining the depth information of the target object in a large area in a scanning manner.

[0181] Figure 15 FIG. shows a schematic diagram of the one-dimensional line light spot performing a scanning action in an embodiment of the present application. Figure 16 FIG. shows a schematic diagram of the one-dimensional line light spot performing a scanning action in an embodiment of the present application. Figure 17The figure shows a schematic diagram of a one-dimensional line light spot performing a scanning action in an embodiment of the present application.

[0182] Refer to Figures 15 to 17 , in an embodiment, the light source 2 includes multiple rows of first sub-light sources 21 and multiple columns of second sub-light sources 22, and the first sub-light sources 21 and the second sub-light sources 22 are arranged in an interleaved manner. Each row of the first sub-light sources 21 serves as a first type of light source unit respectively, and each first type of light source unit projects a horizontal one-dimensional line light spot on the target plane. Moreover, each column of the second sub-light sources 22 serves as a second type of light source unit respectively, and each second type of light source unit projects a vertical one-dimensional line light spot on the target plane.

[0183] In this embodiment, by sequentially lighting up each first type of light source unit, the horizontal one-dimensional line light spot obtained by projection can perform a scanning action along the vertical direction; by sequentially lighting up each second type of light source unit, the vertical one-dimensional line light spot obtained by projection can perform a scanning action along the horizontal direction.

[0184] Specifically, as Figure 15 shown, continuously light up the second type of light source unit at the middle position, so that the corresponding second optical signal 320 continuously projects a vertical one-dimensional line light spot at the middle position on the target plane. At the same time, from top to bottom, sequentially light up each first type of light source unit. In this way, the horizontal one-dimensional line light spot obtained by projection of the first optical signal 310 corresponding to each first type of light source unit performs a scanning action along the vertical direction.

[0185] As Figure 16 shown, continuously light up the first type of light source unit at the middle position, so that the corresponding first optical signal 310 continuously projects a horizontal one-dimensional line light spot at the middle position on the target plane. At the same time, from left to right, sequentially light up each second type of light source unit. In this way, the vertical one-dimensional line light spot obtained by projection of the second optical signal 320 corresponding to each second type of light source unit performs a scanning action along the horizontal direction.

[0186] As Figure 17 shown, from top to bottom, sequentially light up each first type of light source unit. At the same time, from left to right, sequentially light up each second type of light source unit. In this way, the horizontal one-dimensional line light spot performs a scanning action along the vertical direction, and at the same time, the vertical one-dimensional line light spot performs a scanning action along the horizontal direction.

[0187] Embodiment 1

[0188] In the optical emission module provided in Embodiment 1, the first optical signal 310 modulated and output by the meta-lens 1 is used to project a light spot array, and the second optical signal 320 is used to provide floodlighting.

[0189] Figure 18Shows the schematic layout of the sub-light sources in the light source 2 in the optical emission module provided in Embodiment 1. Refer to Figure 18 , in the optical emission module provided in Embodiment 1, the light source 2 includes a plurality of periodically arranged light source units, and each light source unit includes three first sub-light sources 21 for providing a first incident light 210 and one second sub-light source 22 for providing a second incident light 220. Both the first sub-light source 21 and the second sub-light source 22 are VCSELs (Vertical Cavity Surface-Emitting Lasers). The central wavelength of the first incident light 210 emitted by the first sub-light source 21 is 1550 nm, and the central wavelength of the second incident light 220 emitted by the second sub-light source 22 is 527 nm.

[0190] The size of each sub-light source is the same, and the spacing between adjacent sub-light sources is the same. Denote the spacing between adjacent sub-light sources as d, and the half divergence angle of the second incident light 220 emitted by each second sub-light source 22 as θ 2 , and the spacing between the light source 2 and the metalens 1 is L. Then control L * tan(θ 2 ) ≤ d, so that the second incident lights 220 emitted by the second sub-light sources 22 do not interfere with each other when illuminating the metalens 1.

[0191] Figure 19 Shows the schematic diagram of the first phase distribution provided by the metalens 1 for the first incident light 210 in the optical emission module provided in Embodiment 1. Figure 20 Shows the schematic diagram of the second phase distribution provided by the metalens 1 for the second incident light 220 in the optical emission module provided in Embodiment 1. Figure 21 Shows the schematic diagram of the light spot array obtained by projection when the optical emission module provided in Embodiment 1 outputs the first optical signal 310. Figure 22 Shows the schematic diagram of the floodlighting provided when the optical emission module provided in Embodiment 1 outputs the second optical signal 320.

[0192] Refer to Figures 19 to 22 , in Embodiment 1, the first phase distribution provided by the metalens 1 for the first incident light 210 is designed by using the GS (Gerchberg-Saxton) algorithm to modulate the first incident light 210 and output the first optical signal 310, and then project and obtain Figure 21 the light spot array shown.

[0193] The second phase distribution provided by the metalens 1 for the second incident light 22 only exists in each second sub-metalens region ( Figure 20The periodically arranged rectangular regions shown (i.e., the second sub-superlens regions) respectively provide collimation phases. The collimation phases in each second sub-superlens region satisfy the following formula:

[0194]

[0195] where is the collimation phase, λ is the central wavelength of the second incident light 220, f is the focal length of the superlens 1, r is the polar coordinate of the corresponding second sub-superlens region, is the constant phase.

[0196] The superlens 1 modulates the second incident light 220 by providing a second phase distribution, outputs a second optical signal 320, and further provides Figure 22 the flood illumination shown at a working distance of 1.2 m.

[0197] Embodiment 2

[0198] In the optical emission module provided by Embodiment 2, both the first optical signal 310 and the second optical signal 320 modulated and output by the superlens 1 are used to project a light spot array. The first optical signal 310 is used to project a high-density light spot array at a short distance, and the second optical signal 320 is used to project a low-density light spot array at a long distance.

[0199] The optical emission module provided by Embodiment 2, in addition to including the superlens 1 and the light source 2, further includes a polarizer for adjusting the polarization state, and the polarizer is arranged between the superlens 1 and the light source 2. The light source 2 includes 4*4 arrayed VCSELs, and the central wavelength of the emitted light of each VCSEL is 940 nm. The polarizer is used to adjust the polarization state of the incident light of the superlens 1.

[0200] When the polarizer adjusts the light beam emitted by the light source 2 to linearly polarized light in the first polarization direction, the superlens 1 receives the first incident light 210, provides a first phase distribution to the first incident light 210, and modulates and outputs to obtain the first optical signal 310.

[0201] When the polarizer adjusts the light beam emitted by the light source 2 to linearly polarized light in the second polarization direction, the superlens 1 receives the second incident light 220, provides a second phase distribution to the second incident light 220, and modulates and outputs to obtain the second optical signal 320. The first polarization direction is perpendicular to the second polarization direction.

[0202] When the polarizer adjusts the light beam emitted by the light source 2 into linearly polarized light in the third polarization direction (the third polarization direction is in the same plane as the first polarization direction and the second polarization direction, but is neither parallel to the first polarization direction nor parallel to the second polarization direction. Therefore, the linearly polarized light in the third polarization direction can be regarded as the combined light of the linearly polarized light in the first polarization direction and the linearly polarized light in the second polarization direction, that is, the linearly polarized light in the third polarization direction can provide the linearly polarized light in the first polarization direction and the linearly polarized light in the second polarization direction at the same time; preferably, the angle between the third polarization direction and the first polarization direction is 45°, and the angle between the third polarization direction and the second polarization direction is also 45°, thereby ensuring that the light energy of the linearly polarized light in the first polarization direction is equal to the light energy of the linearly polarized light in the second polarization direction), the metalens 1 receives the first incident light 210 and provides a first phase distribution for the first incident light 210, and modulates and outputs to obtain a first optical signal 310; at the same time, the metalens 1 also receives the second incident light 220 and provides a second phase distribution for the second incident light 220, and modulates and outputs to obtain a second optical signal 320.

[0203] Figure 23 Shows the target image used when designing the first phase distribution by using the GS algorithm in Embodiment 2. Figure 24 Shows the target image used when designing the second phase distribution by using the GS algorithm in Embodiment 2. Figure 25 Shows a schematic diagram of the light spot array projected when the optical emission module provided in Embodiment 2 outputs the first optical signal 310. Figure 26 Shows a schematic diagram of the light spot array projected when the optical emission module provided in Embodiment 2 outputs the second optical signal 320.

[0204] Figure 27 Shows a schematic diagram of the light spot array projected when the optical emission module provided in Embodiment 2 outputs the first optical signal 310 and the second optical signal 320 at the same time.

[0205] See Figures 23 to 27 , in Embodiment 2, the first phase distribution provided by the metalens 1 for the first incident light 210 and the second phase distribution provided by the metalens 1 for the second incident light 220 are both designed by using the GS algorithm. Specifically, Figure 23 The target image shown contains 5*5 points, Figure 24 The target image shown includes 3*3 points.

[0206] Then, using the GS algorithm and using the Figure 23 shown target image, the first phase distribution is designed; so that when the metalens 1 only receives the first incident light 210, after the first phase distribution modulates the first incident light 210, the Figure 25 shown light spot array is projected.Figure 25 The pattern of the light spot array shown is equivalent to replicating the pattern of the 4×4 light source 2 twenty-five times in a 5×5 manner.

[0207] Similarly, using the GS algorithm and using Figure 24 the target image shown, a second phase distribution is designed; so that when the metalens 1 only receives the second incident light 220, after the second phase distribution modulates the second incident light 220, the projected light spot array shown is obtained. Figure 26 shown. Figure 26 The pattern of the light spot array shown is equivalent to replicating the pattern of the 4×4 light source 2 nine times in a 3×3 manner.

[0208] Example 2, when the metalens 1 simultaneously receives the first incident light 210 and the second incident light 220, the first phase distribution modulates the first incident light 210, and at the same time, the second phase distribution modulates the second incident light 220, and then the projected light spot array shown is obtained. Figure 27 shown. Figure 27 The light spot array shown simultaneously includes Figure 25 the light spot array shown and Figure 26 the light spot array shown.

[0209] Example 3

[0210] In the optical emission module provided in Example 3, the first optical signal 310 modulated and output by the metalens 1 is used to project a light spot array, and the second optical signal 320 is used to project a one-dimensional line light spot.

[0211] The optical emission module provided in Example 3 includes a metalens 1 and a light source 2. The light source 2 includes multiple rows of first sub-light sources 21 and multiple rows of second sub-light sources 22, and the first sub-light sources 21 and the second sub-light sources 22 are arranged alternately; the first incident light 210 provided by the first sub-light source 21 is linearly polarized light in a first polarization direction; the second incident light 220 provided by the second sub-light source 22 is linearly polarized light in a second polarization direction; the first polarization direction is perpendicular to the second polarization direction; each sub-light source is a VCSEL.

[0212] Figure 28 Shows a schematic diagram of the first phase distribution provided by the metalens 1 for the first incident light 210 in the optical emission module provided in Example 3. Figure 29 Shows a schematic diagram of the second phase distribution provided by the metalens 1 for the second incident light 220 in the optical emission module provided in Example 3. Figure 30 Shows a schematic diagram of the light spot array obtained by projection when the optical emission module provided in Example 3 outputs the first optical signal 310. Figure 31Shows a schematic diagram of the one-dimensional line spot obtained by projection when the optical emission module provided in Embodiment 3 outputs the second optical signal 320.

[0213] In Embodiment 3, the first phase distribution provided by the metalens 1 for the first incident light 210 is as Figure 28 shown, including a collimation phase and a point cloud phase.

[0214] The collimation phase in the first phase distribution satisfies the following formula:

[0215]

[0216] where is the collimation phase, λ is the central wavelength of the first incident light 210, f is the focal length of the metalens 1, r is the polar coordinate on the surface of the metalens 1, is a constant phase.

[0217] The point cloud phase in the first phase distribution is used to replicate the pattern of the light source array formed by the first sub-light sources 21 by 7×11 times. The point cloud phase can be designed using algorithms such as the GS algorithm and the iterative Fourier transform algorithm.

[0218] All the first sub-light sources 21 are lit, and the first incident light 210 emitted by all the first sub-light sources 21 is provided to the metalens 1; then the metalens 1 provides the first phase distribution for the first incident light 210, outputs the first optical signal 310, and then projects to obtain Figure 31 the light spot array shown.

[0219] In Embodiment 3, the second phase distribution provided by the metalens 1 for the second incident light is as Figure 29 shown, including a collimation phase and a shaping phase.

[0220] The collimation phase in the second phase distribution is the same as the collimation phase in the first phase distribution, and will not be elaborated here.

[0221] The shaping phase in the second phase distribution is used to shape the second incident light 220 provided by the single-row second sub-light sources 22 into a one-dimensional line spot. The shaping phase can be designed using the GS algorithm and the light intensity mapping method.

[0222] From top to bottom, the second sub-light sources 22 in each row are lit in a time-sharing manner (only one row of second sub-light sources 22 is lit at the same time). In this way, as Figure 31 shown, the metalens 1 provides the second phase distribution for the second incident light 220 provided by the single-row second sub-light sources 22, outputs the second optical signal 320, and projects to obtain a horizontal one-dimensional line spot; moreover, the projected horizontal one-dimensional line spot performs a scanning action along the vertical direction.

[0223] Embodiment 4

[0224] In the optical emission module provided in Embodiment 4, the first optical signal 310 modulated and output by the metalens 1 is used to project a horizontal one-dimensional line spot, and the second optical signal 320 is used to project a vertical one-dimensional line spot.

[0225] The optical emission module provided in Embodiment 4 includes a metalens 1 and a light source 2. The light source 2 includes multi-row and multi-column dual-polarization multimode VCSELs, and each sub-light source can be selectively configured as a first sub-light source 21 for providing a first incident light 210 or a second sub-light source 22 for providing a second incident light 220. Thus, the light source 2 is configured to include multi-row first sub-light sources 21 and multi-column second sub-light sources 22; the central wavelength of the light beam emitted by each sub-light source is 850 nm. Among them, the first incident light 210 is linearly polarized light in a first polarization direction, and the second incident light 220 is linearly polarized light in a second polarization direction; the first polarization direction is perpendicular to the second polarization direction.

[0226] Figure 32 The figure shows a schematic diagram of the first phase distribution provided by the metalens 1 for the first incident light 210 in the optical emission module provided in Embodiment 4. Figure 33 The figure shows a schematic diagram of the second phase distribution provided by the metalens 1 for the second incident light 220 in the optical emission module provided in Embodiment 4. Figure 34 The figure shows a schematic diagram of the one-dimensional line spot obtained by projection when the optical emission module provided in Embodiment 4 outputs the first optical signal 310. Figure 35 The figure shows a schematic diagram of the one-dimensional line spot obtained by projection when the optical emission module provided in Embodiment 4 outputs the second optical signal 320. Figure 36 The figure shows a schematic diagram of the cross-shaped spot obtained by projection when the optical emission module provided in Embodiment 4 outputs the first optical signal 310 and the second optical signal 320 simultaneously.

[0227] In Embodiment 4, the first phase distribution provided by the metalens 1 for the first incident light 210 is as Figure 32 shown, including a collimation phase and a shaping phase.

[0228] The collimation phase in the first phase distribution satisfies the following formula:

[0229]

[0230] where is the collimation phase, λ is the central wavelength of the first incident light 210, f is the focal length of the metalens 1, r is the polar coordinate on the surface of the metalens 1, is the constant phase.

[0231] The shaping phase in the first phase distribution is used to shape the first incident light 210 emitted by the single-row first sub-light source 21 into a horizontal one-dimensional line spot. The shaping phase in the first phase distribution can be designed using the GS algorithm or the intensity mapping method.

[0232] Light up the single-row first sub-light source 21 and provide the first incident light 210 provided by the single-row first sub-light source 21 to the metalens 1; then, the metalens 1 provides a first phase distribution for the first incident light 210, outputs a first optical signal 310, and then projects to obtain Figure 34 The horizontal one-dimensional line spot shown.

[0233] In Embodiment 4, the first phase distribution provided by the metalens 1 for the second incident light 220 is as Figure 33 Shown, including a collimation phase and a shaping phase.

[0234] The collimation phase in the second phase distribution is the same as the collimation phase in the first phase distribution and will not be elaborated here.

[0235] The shaping phase in the second phase distribution is used to shape the second incident light 220 emitted by the single-column second sub-light source 22 into a vertical one-dimensional line spot. The shaping phase in the second phase distribution can also be designed using the GS algorithm or the intensity mapping method.

[0236] Light up the single-column second sub-light source 22 and provide the second incident light 220 provided by the single-column second sub-light source 22 to the metalens 1; then, the metalens 1 provides a second phase distribution for the second incident light 220, outputs a second optical signal 320, and then projects to obtain Figure 35 The vertical one-dimensional line spot shown.

[0237] In Embodiment 4, when the single-row first sub-light source 21 and the single-column second sub-light source 22 are lit simultaneously, the metalens 1 provides a first phase distribution for the received first incident light 210, and at the same time, provides a second phase distribution for the received second incident light 220, and then projects to obtain Figure 36 The crosshair spot shown.

[0238] After considering the specification and practicing the disclosed utility model herein, those skilled in the art will readily conceive of other embodiments of the present application. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include known common knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and embodiments are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the appended claims.

Claims

1. A metalens for an optical emission module, characterized in that: The superlens includes a substrate and a micro-nano structure disposed on the substrate; the superlens is used to receive at least one of the first incident light and the second incident light, and modulate the received incident light; wherein the target physical property of the first incident light is different from the target physical property of the second incident light; The metalens modulates the first incident light into a first optical signal by providing a first phase distribution; the metalens modulates the second incident light into a second optical signal by providing a second phase distribution; the first phase distribution and the second phase distribution are different from and independent of each other; At least one of the first optical signal and the second optical signal is used to obtain depth information of a target object; and a composite optical signal composed of the first optical signal and the second optical signal is used to enhance the depth information.

2. The metalens according to claim 1, characterized in that Target physical properties of the incident light include: the central wavelength of the light beam; or, the polarization state of the light beam.

3. The metalens according to claim 2, characterized in that When the target physical property of the incident light includes the polarization state of the light beam, the micro-nanostructure is polarization dependent.

4. The metalens according to claim 1, wherein: The first optical signal is used to project a light spot array, and the second optical signal is used to provide flood lighting; The composite optical signal is used to enhance the depth information in a manner that information accuracy and information resolution complement each other.

5. The metalens according to claim 1, wherein: The first optical signal is used to project a line of light spots, and the second optical signal is used to provide flood lighting; The composite optical signal is used to enhance the depth information in an information denoising manner.

6. The metalens according to claim 4 or 5, characterized in that The second incident light comes from at least two sub-light sources, and the second incident light from different sub-light sources covers the corresponding second sub-super-lens areas on the super-lens respectively; The second sub-super lens regions do not overlap with each other, and the second phase distribution includes the collimated phases respectively provided by the super lens on the second sub-super lens regions.

7. The metalens according to claim 1, wherein: The first optical signal is used to project a light spot array or a line light spot, and the second optical signal is used to project a light spot array or a line light spot; The composite optical signal is used to enhance the depth information in an information fusion manner.

8. The superlens according to claim 7, characterized in that A target working distance of the light spot projected by the first optical signal is different from a target working distance of the light spot projected by the second optical signal.

9. The superlens according to claim 7, characterized in that The light spot projected by the first optical signal and the light spot projected by the second optical signal have at least partial non-overlapping light spot areas at the same target working distance.

10. An optical emission module, characterized in that: The optical emission module comprises: a light source; a super lens as described in any one of claims 1 to 9; The light source is used to provide the first incident light and the second incident light to the superlens in a time-sharing manner, or to provide the first incident light and the second incident light to the superlens at the same time.

11. The optical emission module according to claim 10, characterized in that: The light source includes a first sub-light source for providing the first incident light and a second sub-light source for providing the second incident light; the first sub-light source and the second sub-light source are arranged alternately.

12. The optical emission module according to claim 10, characterized in that: The target physical properties of the incident light include the central wavelength of the beam; The light source comprises a first sub-light source and a second sub-light source having different central wavelengths, the first sub-light source is used to provide the first incident light, and the second sub-light source is used to provide the second incident light; Alternatively, the light source includes a sub-light source with adjustable wavelength to provide the first incident light or the second incident light by adjusting the wavelength.

13. The optical emission module according to claim 10, characterized in that: The target physical properties of the incident light include the polarization state of the beam; The light source comprises a first sub-light source and a second sub-light source having different polarization states, the first sub-light source is used to provide the first incident light, and the second sub-light source is used to provide the second incident light; Alternatively, the light source includes a polarization-adjustable sub-light source to provide the first incident light or the second incident light by adjusting the polarization state; Alternatively, the optical emission module further includes a polarizer, which is disposed between the light source and the superlens, and is used to cooperate with the light source to provide the first incident light or the second incident light.

14. The optical emission module according to claim 10, characterized in that: The first optical signal is used to project a light spot array, and the second optical signal is used to provide flood lighting; The light source includes at least two second sub-light sources arranged at intervals for providing the second incident light; the second incident light emitted by each second sub-light source covers the corresponding second sub-super lens area on the super lens, and the second sub-super lens areas do not overlap with each other.

15. The optical emission module according to claim 14, characterized in that: The second sub-light sources are arranged periodically; The light source includes at least two light source units arranged periodically, and each of the light source units includes one second sub-light source and at least one first sub-light source for providing the first incident light.

16. The optical emission module according to claim 10, characterized in that: At least one of the first optical signal and the second optical signal is used to project a word line light spot; The light source comprises at least two light source units arranged at intervals, and the emitted light of each light source unit is used to project a line light spot; by lighting the light source units in time division, the projected line light spot performs a scanning action.

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