Polarization imaging sensors and electronic devices

Abstract

The present application discloses a polarization imaging sensor and electronic device. The polarization imaging sensor includes: a meta-lens, which decomposes first incident light into first polarization state light and second polarization state light, where the polarization angle of the first polarization state light is different from the polarization angle of the second polarization state light; and a photoelectric device, which includes a first photoelectric unit and a second photoelectric unit, where the first polarization state light is incident on the first photoelectric unit and the second polarization state light is incident on the second photoelectric unit. The present application replaces the design of a polarization filter by designing a meta-lens and a photoelectric device. The meta-lens can vector-decompose the first incident light into first polarization state light and second polarization state light with different polarization angles. The decomposed first polarization state light and second polarization state light with different polarization angles can be focused on the first photoelectric unit and the second photoelectric unit of the photoelectric device, respectively, thereby ensuring the extinction ratio of the polarization imaging sensor while effectively improving the transmittance.

Description

Technical Field

[0001] The present application belongs to the technical field of electronic products, and in particular relates to a polarization imaging sensor and an electronic device having the polarization imaging sensor. Background Art

[0002] Traditional image sensors can only perceive certain parameters of light, such as brightness, color, and direction of propagation, but cannot record its polarization properties. Polarization imaging sensors, on the other hand, can visualize the polarization properties (the direction of light wave vibration) of light, which is imperceptible to the human eye, enriching application scenarios.

[0003] Existing polarization imaging sensors typically consist of a polarizing filter, a microlens, and a photodiode. The polarizing filter, typically constructed from a metal grating with linear slits, only allows light with a specific vector vibration direction to pass through, while absorbing (or reflecting) light with perpendicular vibrations. To achieve a high extinction ratio (ER) in polarization imaging sensors, the polarizing filter significantly reduces the pixel transmittance, making it difficult to balance the extinction ratio and transmittance characteristics of the polarizing filter. Summary of the Invention

[0004] The present application aims to provide a polarization imaging sensor and electronic device, which can at least solve the problem in the prior art that polarization imaging sensors cannot take into account both extinction ratio and transmittance at the same time.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a polarization imaging sensor, comprising: a metalens, which decomposes first incident light into first polarization state light and second polarization state light, wherein the polarization angle of the first polarization state light is different from the polarization angle of the second polarization state light; and a photoelectric device, comprising a first photoelectric unit and a second photoelectric unit, wherein the first polarization state light is incident on the first photoelectric unit and the second polarization state light is incident on the second photoelectric unit.

[0007] In a second aspect, an embodiment of the present application provides an electronic device, comprising the polarization imaging sensor in the above embodiment.

[0008] In the embodiments of the present application, by designing a meta-lens and an optoelectronic device, instead of a polarizing filter, the meta-lens can vector-decompose the first incident light into a first polarization state light and a second polarization state light with different polarization angles. The decomposed first polarization state light and the second polarization state light with different polarization angles can be focused onto the first optoelectronic unit and the second optoelectronic unit of the optoelectronic device, respectively, thereby ensuring the extinction ratio of the polarization imaging sensor while effectively improving the transmittance.

[0009] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0011] Figure 1 is a schematic structural diagram of a polarization imaging sensor according to an embodiment of the present invention;

[0012] Figure 2 is an exploded schematic diagram of a polarization imaging sensor according to an embodiment of the present invention;

[0013] Figure 3 is a cross-sectional view of a polarization imaging sensor according to an embodiment of the present invention;

[0014] Figure 4 is another cross-sectional view of a polarization imaging sensor according to an embodiment of the present invention;

[0015] Figure 5 2 is a schematic structural diagram of a meta-lens of a polarization imaging sensor according to an embodiment of the present invention;

[0016] Figure 6 is a schematic structural diagram of a microlens of a polarization imaging sensor according to an embodiment of the present invention;

[0017] Figure 7 is a schematic diagram of a light path of a polarization imaging sensor according to an embodiment of the present invention;

[0018] Figure 8 is another light path schematic diagram of a polarization imaging sensor according to an embodiment of the present invention;

[0019] Figure 9 is another schematic diagram of a light path of a polarization imaging sensor according to an embodiment of the present invention;

[0020] Figure 10 is another schematic diagram of a light path of a polarization imaging sensor according to an embodiment of the present invention;

[0021] Figure 11 is a polarization angle diagram corresponding to each pixel of the polarization imaging sensor according to the first embodiment of the present invention;

[0022] Figure 12 yes Figure 11 A partial enlarged view of the middle area A;

[0023] Figure 13is a polarization angle diagram of each pixel of the polarization imaging sensor according to the second embodiment of the present invention;

[0024] Figure 14 yes Figure 13 A partial enlarged view of the middle area B;

[0025] Figure 15 is a graph showing changes in light intensity of a polarization imaging sensor according to embodiment 1 of the present invention as a function of the polarization angle of incident light;

[0026] Figure 16 is an electric field distribution diagram of 0° polarized light incident on the second lens unit in the polarization imaging sensor according to the first embodiment of the present invention;

[0027] Figure 17 is an electric field distribution diagram of 90° polarized light incident on the second lens unit in the polarization imaging sensor according to the first embodiment of the present invention;

[0028] Figure 18 is an electric field distribution diagram of 0° polarized light incident on the second lens unit in the polarization imaging sensor according to the second embodiment of the present invention;

[0029] Figure 19 4 is a diagram of the electric field distribution when 90° polarized light is incident on the second lens unit in the polarization imaging sensor according to the second embodiment of the present invention.

[0030] Reference numerals:

[0031] Polarization imaging sensor 100;

[0032] Metalens 10; microlens 11; first lens unit 111; second lens unit 112; third lens unit 113; fourth lens unit 114;

[0033] Photoelectric device 20; first photoelectric unit 21; second photoelectric unit 22; third photoelectric unit 23; fourth photoelectric unit 24;

[0034] Fixed layer 30;

[0035] Filling layer 40;

[0036] First incident light 51; second incident light 52;

[0037] First polarization state light 61; second polarization state light 62. DETAILED DESCRIPTION

[0038] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and are not to be construed as limiting the present invention. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of this application.

[0039] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly refer to one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more. Furthermore, the term "and / or" in the specification and claims refers to at least one of the connected entities, and the character " / " generally indicates an "or" relationship between the connected entities.

[0040] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0041] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0042] The polarization imaging sensor 100 provided in the embodiment of the present application is described in detail below through specific embodiments and application scenarios in conjunction with the accompanying drawings.

[0043] like Figures 1 to 10 As shown, a polarization imaging sensor 100 according to an embodiment of the present invention includes a meta-lens 10 and an optoelectronic device 20 .

[0044] Specifically, the metalens 10 decomposes the first incident light 51 into a first polarized light 61 and a second polarized light 62. The polarization angle of the first polarized light 61 is different from the polarization angle of the second polarized light 62. The optoelectronic device 20 includes a first optoelectronic unit 21 and a second optoelectronic unit 22. The first polarized light 61 is incident on the first optoelectronic unit 21, and the second polarized light 62 is incident on the second optoelectronic unit 22.

[0045] In other words, see Figure 1 and Figure 2 , the polarization imaging sensor 100 according to an embodiment of the present invention is mainly composed of a metalens 10 and a photoelectric device 20. Among them, the metalens 10 (metalens, ML) can converge light beams and arbitrarily control the amplitude, phase and polarization of light. After the light beams with different polarization directions converge on the metalens 10, the converged light beams are vector decomposed by the metalens 10. Among them, assuming that the propagation direction of light is z, it is set that when the polarization direction of light is consistent with the x direction, it is 0° polarized light, and when it is consistent with the y direction, it is 90° polarized light. Other light rays with a certain angle of polarization to the x or y direction can be converted into small polarized light in the x and y directions according to vector decomposition through the metalens 10.

[0046] See also Figure 7 and Figure 9 When the first incident light 51 enters the meta-lens 10, the meta-lens 10 can decompose the first incident light 51 into a first polarization state light 61 and a second polarization state light 62. The polarization angle of the first polarization state light 61 is different from the polarization angle of the second polarization state light 62 ( Figure 9 Where α and β represent polarization angles respectively). The first polarized light can be understood as polarized light in the x direction, and the second polarized light can be understood as polarized light in the y direction. Figure 10 , the difference between the polarization angles of the first polarized light 61 and the second polarized light 62 is 90°. The first polarized light after decomposition of the first incident light 51 can be incident on the first photoelectric unit 21 of the photoelectric device 20. The second polarized light after decomposition of the first incident light 51 can be incident on the second photoelectric unit 22 of the photoelectric device 20. By having the light beams after vector decomposition by the metalens 10 be incident on the first photoelectric unit 21 and the second photoelectric unit 22 respectively, it is beneficial to fully utilize the light beams with different polarization directions, ensuring that the light beams with different polarization directions can all be incident on the photoelectric device 20 after decomposition, while maintaining the extinction ratio, and greatly improving the transmittance.

[0047] Therefore, according to the polarization imaging sensor 100 of the embodiment of the present invention, by designing the optoelectronic device 20 and the metalens 10, the polarization filter design is replaced. The metalens 10 can vector-decompose the converged light beams with different polarization angles. The decomposed light beams can all be focused on the optoelectronic device 20, ensuring the extinction ratio of the polarization imaging sensor 100 while effectively improving the transmittance and light utilization rate, thereby enhancing the performance of the sensor.

[0048] According to one embodiment of the present invention, the second incident light 52 passes through the metalens 10 and is incident on the first photoelectric unit 21. The polarization angle of the second incident light 52 is the same as the polarization angle of the first polarized light 61. The polarization angle of the second incident light 52 is different from the polarization angle of the first incident light 51. The first photoelectric unit 21 receives and records the first polarized light 61 obtained by decomposing the first incident light 51 after passing through the metalens 10, as well as the second incident light 52 after passing through the metalens 10.

[0049] That is to say, if Figure 8 and Figure 9 As shown, when the second incident light 52 enters the metalens 10, the polarization angle of the second incident light 52 is the same as the polarization angle of the first polarized light 61, and the polarization angle of the second incident light 52 is different from the polarization angle of the first incident light 51. Since the polarization angle of the second incident light 52 is the same as the polarization angle of the first polarized light 61, the second incident light 52 directly passes through the metalens and is incident on the first photoelectric unit. The first photoelectric unit 21 can receive and record the first polarized light 61 obtained by decomposing the first incident light 51 after passing through the metalens 10, as well as the second incident light 52 after passing through the metalens 10, thereby ensuring that the polarization imaging sensor 100 can fully utilize the light beams of other polarization directions, so that the light beams of different polarization directions can all be focused on the photoelectric device 20 after being decomposed.

[0050] The embodiments of the present application can not only allow the incident polarized light that meets the requirements to be converged to the corresponding photoelectric unit, but also can converge the remaining incident polarized light whose polarization angle does not meet the requirements and which was originally eliminated in the prior art to the corresponding photoelectric unit through vector decomposition, thereby ensuring the extinction ratio while greatly improving the transmittance.

[0051] According to one embodiment of the present invention, Figure 2 and Figure 5As shown, the meta-lens 10 is primarily composed of a first lens unit 111 and a second lens unit 112. The first lens unit 111 is disposed opposite the first photoelectric unit 21, and the second lens unit 112 is disposed opposite the second photoelectric unit 22. The first lens unit 111 and the first photoelectric unit 21 may correspond to each other in the height direction (z-direction), and the second lens unit 112 and the second photoelectric unit 22 may also correspond to each other in the height direction. After passing through the first lens unit 111, the first incident light is decomposed by the first lens unit 111 into a first polarized light 61 and a second polarized light 62. The first polarized light 61 is incident on the first photoelectric unit 21, and the second polarized light 62 is incident on the second photoelectric unit 22. Similarly, after passing through the second lens unit 112, the first incident light 51 is also decomposed by the second lens unit 112 into a first polarized light 61 and a second polarized light 62. The first polarized light 61 is incident on the first photoelectric unit 21, and the second polarized light 62 is incident on the second photoelectric unit 22.

[0052] See also Figure 5 、 Figure 12 and Figure 13 The first lens unit 111 and the second lens unit 112 each include a plurality of microlenses 11. The plurality of microlenses in the second lens unit 112 are deflected by a first angle ( Figure 5 、 Figure 12 and Figure 14 Where θ represents the first angle. The difference between the polarization angles of the first polarization state light 61 and the second polarization state light 62 is equal to the first angle.

[0053] In this application, if Figure 5 and Figure 6 As shown, each microlens 11 can be designed as a nanocolumn, and each nanocolumn in the second lens unit 112 corresponds to each nanocolumn in the first lens unit 111. At the same time, each nanocolumn in the second lens unit 112 is deflected by a first angle (see Figure 5 Wherein, the difference between the polarization angle of the first polarization state light 61 and the polarization angle of the second polarization state light 62 is equal to the first angle.

[0054] like Figure 11 and Figure 12 As shown in FIG, the first angle can be 0°, 45°, 90° or 135°. For example, when the polarization angle of the first polarization state light 61 is 90° and the polarization angle of the second polarization state light 62 is 0°, then, as shown in FIG. Figure 10As shown, when the first polarized light 61 passes through the first lens unit 111, it can be focused on the first photoelectric unit 21 in the main axis direction (height direction) of the first lens unit 111, and when the second polarized light 62 passes through the first lens unit 111, it can be focused on the second photoelectric unit 22 on the side. Figure 10 When the second polarized light 62 passes through the second lens unit 112, it can be focused on the second photoelectric unit 22 in the main axis direction of the second lens unit 112. When the first polarized light 61 passes through the second lens unit 112, it can be focused on the first photoelectric unit 21 on the side.

[0055] Therefore, the degree and direction of polarization can be calculated through the light intensity information recorded by each photoelectric unit, which is conducive to achieving tasks that are difficult for traditional image sensors to do, such as object shape recognition, elimination of interfering reflected light on water or glass surfaces, deformation and scratch detection, etc., providing electronic devices with richer application scenarios and expanding the application scope of imaging technology.

[0056] In some specific embodiments of the present invention, the metalens 10 includes a plurality of microlenses 11 , and the lengths, widths, heights, or side extension directions of the plurality of microlenses 11 are different.

[0057] In other words, Figure 2 and Figure 5 As shown, the meta-lens 10 includes a plurality of micro-lenses 11, each of which can be configured as a nano-pillar. The plurality of nano-pillar micro-lenses 11 can be arranged in an array, and the length, width, height, or side extension direction of the plurality of micro-lenses 11 can be different. When the height (H) of the anisotropic micro-lens 11 is constant, different equivalent refractive indices can be provided for 0° polarized light and 90° polarized light by adjusting the structural parameters of the nano-pillar (micro-lens 11), such as the length (L), width (W), and setting angle of the micro-lens. The sum of the phase delays along the fast axis and the slow axis of each micro-lens 11 will result in a phase profile sensitive to linear polarization, thereby achieving polarization multiplexing. It should be noted that in the drawings of this application, x, y, and z respectively represent three-dimensional directions, which is understandable and achievable for those skilled in the art and will not be described in detail in this application.

[0058] According to one embodiment of the present invention, Figure 2 and Figure 5As shown, the metalens 10 includes a first lens unit 111 and a second lens unit 112. The first lens unit 111 is disposed opposite the first photoelectric unit 21, and the second lens unit 112 is disposed opposite the second photoelectric unit 22. The first lens unit 111 and the second lens unit 112 each include a plurality of microlenses 11, and each microlens in the second lens unit 112 is rotated by the same angle relative to its own axis as each microlens in the first lens unit 111. Among them, compared with each microlens 11 in the first lens unit 111 and each microlens 11 in the second lens unit 112, one of the corresponding two microlenses 11 can be rotated by 0°, 45°, 90°, or 135° relative to the corresponding microlens 11. Therefore, the first lens unit 111 and the second lens unit can focus polarized light of 0°, 45°, 90°, and 135° onto their respective corresponding photoelectric units according to the different polarization directions of the incident light, ensuring that light of different polarization states after vector decomposition of the incident light can be focused onto the corresponding photoelectric units, thereby ensuring the extinction ratio of the polarization imaging sensor 100 while effectively improving the transmittance.

[0059] In this application, if Figure 2 and Figure 10 As shown, each lens unit in the metalens 10 and each optoelectronic unit in the optoelectronic device 20 completely correspond in the height direction (z direction), together forming a pixel. Each lens unit can focus polarized light of 0°, 45°, 90°, and 135° onto its corresponding optoelectronic unit, depending on the polarization state of the incident light. The light intensity information recorded by each optoelectronic unit can be used to calculate the degree and direction of polarization, facilitating tasks that are difficult for traditional image sensors to accomplish, such as object shape recognition, eliminating interfering reflected light from water or glass surfaces, and detecting deformation and scratches. This provides a richer range of application scenarios for electronic devices and expands the application scope of imaging technology.

[0060] According to one embodiment of the present invention, Figure 2 and Figure 5 As shown, the meta-lens 10 includes a first lens unit 111 and a second lens unit 112. The first lens unit 111 is arranged opposite to the first photoelectric unit 21, and the second lens unit 112 is arranged opposite to the second photoelectric unit 22. The first lens unit 111 and the second lens unit 112 each include a plurality of micro lenses 11. The plurality of micro lenses 11 in the first lens unit 111 and the second lens unit 112 are respectively arranged in an array. Figure 11 and Figure 12The microlenses 11 in the nth row and mth column of the first lens unit 111 and the microlenses 11 in the nth row and mth column of the second lens unit 112 are symmetrical. Here, n ≥ 1 and m ≥ 1. This allows polarized light with different polarization angles to be focused onto their corresponding optoelectronic units, making full use of light beams with different polarization directions and ensuring that all decomposed light beams with different polarization directions are focused onto the optoelectronic device 20. This effectively improves the extinction ratio while also significantly increasing light transmittance.

[0061] In some specific embodiments of the present invention, Figure 13 and Figure 14 As shown, the first lens unit 111 and the second lens unit 112 are distributed diagonally. The multiple microlenses 11 in the first lens unit 111 and the second lens unit 112 are respectively distributed in an array. The microlens 11 in the nth row and mth column of the first lens unit 111 is rotated by a first angle relative to the microlens 11 in the nth row and mth column of the second lens unit 112, where n ≥ 1 and m ≥ 1. The first angle can be 45° or 90°, thereby focusing polarized light with different polarization angles onto their corresponding different photoelectric units, which is conducive to fully utilizing light beams with different polarization directions and ensuring that light beams with different polarization directions can all be focused on the photoelectric device 20 after being decomposed, effectively improving the extinction ratio while greatly improving the transmittance.

[0062] According to one embodiment of the present invention, Figure 2 and Figure 5 As shown, the meta-lens 10 includes a first lens unit 111, a second lens unit 112, a third lens unit 113, and a fourth lens unit 114. The first lens unit 111, the second lens unit 112, the third lens unit 113, and the fourth lens unit 114 correspond substantially to Figure 5 The range of each dotted circle.

[0063] like Figure 5 As shown, the first lens unit 111, the second lens unit 112, the third lens unit 113 and the fourth lens unit 114 each include a plurality of micro lenses 11. Figure 11 and Figure 12 The plurality of microlenses 11 in the first lens unit 111, the second lens unit 112, the third lens unit 113, and the fourth lens unit 114 are arranged in an array, and the first lens unit 111 and the fourth lens unit 114 are arranged diagonally. The first lens unit 111 and the second lens unit 112 are arranged in a horizontal direction.

[0064] like Figure 12As shown, the microlens 11 in the nth row and mth column of the first lens unit 111 is rotated 90° relative to the microlens 11 in the nth row and mth column of the second lens unit 112. The microlens 11 in the nth row and mth column of the third lens unit 113 is rotated 90° relative to the microlens 11 in the nth row and mth column of the fourth lens unit 114. Furthermore, the microlens 11 in the nth row and mth column of the third lens unit 113 is rotated 45° relative to the microlens 11 in the nth row and mth column of the first lens unit 111, where n≥1 and m≥1.

[0065] In the present application, the optoelectronic device 20 further includes a third optoelectronic unit 23 and a fourth optoelectronic unit 24 , the first lens unit 111 is arranged opposite to the first optoelectronic unit 21 , the second lens unit 112 is arranged opposite to the second optoelectronic unit 22 , the third lens unit 113 is arranged opposite to the third optoelectronic unit 23 , and the fourth lens unit 114 is arranged opposite to the fourth optoelectronic unit 24 .

[0066] The meta-lens 10 decomposes the first incident light 51 into a first polarization state light 61, a second polarization state light 62, a third polarization state light and a fourth polarization state light. The polarization angle of the first polarization state light 61 is 0°, the polarization angle of the second polarization state light 62 is 90°, the polarization angle of the third polarization state light is 45°, and the polarization angle of the fourth polarization state light is 135°.

[0067] In the present application, the optoelectronic device 20 further includes a third optoelectronic unit 23 and a fourth optoelectronic unit 24 . The third polarization state light is incident on the third optoelectronic unit 23 , and the fourth polarization state light is incident on the fourth optoelectronic unit 24 .

[0068] Specifically, if Figure 2 and Figure 5 As shown, a plurality of micro lenses 11 form four lens units, and the four lens units are a first lens unit 111, a second lens unit 112, a third lens unit 113 and a fourth lens unit 114 arranged in an array. The first lens unit 111, the second lens unit 112, the third lens unit 113 and the fourth lens unit 114 are respectively Figure 2 The optoelectronic device 20 includes a first optoelectronic unit 21 , a second optoelectronic unit 22 , a third optoelectronic unit 23 and a fourth optoelectronic unit 24 corresponding to the four lens units, respectively, to form a picture element.

[0069] Among them, Figure 11 and Figure 12 As shown, the first lens unit 111 and the second lens unit 112 are arranged in sequence in the X direction, the first lens unit 111 and the third lens unit 113 are arranged in sequence in the Y direction, and the second lens unit 112 and the fourth lens unit 114 are arranged in sequence in the Y direction. Figure 3The first lens unit 111 can focus 90° polarized light onto the first photoelectric unit 21 and 0° polarized light onto the second photoelectric unit 22. The second lens unit 112 can focus 0° polarized light onto the second photoelectric unit 22 and 90° polarized light onto the first photoelectric unit 21. The third lens unit 113 can focus 135° polarized light onto the third photoelectric unit 23 and 45° polarized light onto the fourth photoelectric unit 24. The fourth lens unit 114 can focus 45° polarized light onto the fourth photoelectric unit 24 and 135° polarized light onto the third photoelectric unit 23.

[0070] In the present application, each lens unit corresponds to a photoelectric unit in the z direction and together form a pixel. Every group of four pixel units with different designs serves as a calculation unit.

[0071] In this application, the lens unit can focus polarized light of 0°, 45°, 90°, and 135° onto the corresponding different photoelectric units according to the different polarization directions of the incident light. The degree and direction of polarization can be calculated through the light intensity information recorded by the four photoelectric units.

[0072] The first pixel and the second pixel are arranged in sequence in the x direction in a manner that they are spaced apart from each other. Figure 10 、 Figure 11 and Figure 12 As shown, the first lens unit 111 in the first pixel can focus incident light with a polarization direction of 90° onto the first photoelectric unit 21 in the direction of its main axis, and focus incident light with a polarization direction of 0° onto the second photoelectric unit 22 in the second pixel next to it. Correspondingly, the second lens unit 112 in the second pixel can focus incident light with a polarization direction of 0° onto the second photoelectric unit 22 in the direction of its main axis, and focus incident light with a polarization direction of 90° onto the first photoelectric unit 21 of another first pixel next to it.

[0073] Similarly, the third and fourth pixels for modulating 45° and 135° polarized light are arranged in the same manner in the x-direction. Specifically, the third lens unit 113 in the third pixel can focus 135° polarized light onto the third photoelectric unit 23 in the direction of its principal axis, and 45° polarized light onto the fourth photoelectric unit 24 to the side. The fourth lens unit 114 in the fourth pixel can focus 45° polarized light onto the fourth photoelectric unit 24 on the principal axis, and 135° polarized light onto another third photoelectric unit 23 to the side.

[0074] In this embodiment, the polarization angles between the pixels in the x-direction differ by 90°, while the polarization angles between the pixels in the y-direction differ by 45°. Figure 11 and Figure 12As shown, the present application focuses polarized light of 0°, 45°, 90°, and 135° onto the corresponding different photoelectric units, ensuring that light beams of different polarization directions can all be focused onto the photoelectric device 20 after being decomposed, effectively improving the extinction ratio while greatly improving the transmittance.

[0075] According to one embodiment of the present invention, Figure 2 、 Figure 5 、 Figure 13 and Figure 14 As shown, the meta-lens 10 includes a first lens unit 111, a second lens unit 112, a third lens unit 113 and a fourth lens unit 114. The first lens unit 111, the second lens unit 112, the third lens unit 113 and the fourth lens unit 114 each include a plurality of micro lenses 11. Figure 13 and Figure 14 As shown, the multiple microlenses 11 in the first lens unit 111, the second lens unit 112, the third lens unit 113 and the fourth lens unit 114 are respectively distributed in an array, and the first lens unit 111 and the second lens unit 112 are arranged diagonally, and the first lens unit 111 and the third lens unit 113 are arranged in the horizontal direction.

[0076] See also Figure 12 and Figure 13 The microlens 11 in the nth row and mth column of the first lens unit 111 is rotated 45° relative to the microlens 11 in the nth row and mth column of the third lens unit 113, the microlens 11 in the nth row and mth column of the fourth lens unit 114 is rotated 45° relative to the axis of the microlens 11 in the nth row and mth column of the second lens unit 112, and the microlens 11 in the nth row and mth column of the fourth lens unit 114 is rotated 135° relative to the microlens 11 in the nth row and mth column of the first lens unit 111, where n≥1 and m≥1.

[0077] In the present application, the optoelectronic device 20 further includes a third optoelectronic unit 23 and a fourth optoelectronic unit 24 , the first lens unit 111 is arranged opposite to the first optoelectronic unit 21 , the second lens unit 112 is arranged opposite to the second optoelectronic unit 22 , the third lens unit 113 is arranged opposite to the third optoelectronic unit 23 , and the fourth lens unit 114 is arranged opposite to the fourth optoelectronic unit 24 .

[0078] The meta-lens 10 decomposes the first incident light 51 into a first polarization state light 61, a second polarization state light 62, a third polarization state light and a fourth polarization state light. The polarization angle of the first polarization state light 61 is 0°, the polarization angle of the second polarization state light 62 is 90°, the polarization angle of the third polarization state light is 45°, and the polarization angle of the fourth polarization state light is 135°.

[0079] In the present application, the optoelectronic device 20 further includes a third optoelectronic unit 23 and a fourth optoelectronic unit 24 . The third polarization state light is incident on the third optoelectronic unit 23 , and the fourth polarization state light is incident on the fourth optoelectronic unit 24 .

[0080] That is, see Figure 13 and Figure 14 This application changes the design parameters of the nanopillars, altering the arrangement of the first, second, third, and fourth pixels relative to the x-axis, while also matching the polarization angle of the polarized light. By varying the length and width of the lens unit, the propagation phase accumulated by the nanopillars is adjusted, thereby varying the lens unit's response characteristics to various linear polarizations.

[0081] like Figure 13 and Figure 14 As shown, the first lens unit 111 and the third lens unit 113 are arranged sequentially in the X direction, the first lens unit 111 and the fourth lens unit 114 are arranged sequentially in the Y direction, and the second lens unit 112 and the third lens unit 113 are arranged sequentially in the Y direction. The first lens unit 111 in the first pixel can focus 45° polarized light onto the first photoelectric unit 21 on its main axis and 0° polarized light onto the second photoelectric unit 22 to the side. The second lens unit 112 in the second pixel can focus 0° polarized light onto the second photoelectric unit 22 on its main axis and 45° polarized light onto the first photoelectric unit 21 to the side.

[0082] The third lens unit 113 of the third pixel can focus 90° polarized light onto the third photoelectric unit 23 on its main axis, and 135° polarized light onto the fourth photoelectric unit 24 located adjacent to it. The fourth lens unit 114 of the fourth pixel can focus 135° polarized light onto the fourth photoelectric unit 24 on its main axis, and 45° polarized light onto the third photoelectric unit 23 located adjacent to it. In this embodiment, the polarization angle difference between pixels is 45°, regardless of whether it is along the x-direction or the y-direction. This more uniform distribution facilitates subsequent signal processing.

[0083] In some specific embodiments of the present invention, Figures 2 to 4 As shown, the metalens 10 further includes a fixed layer 30. The metalens 10 includes a plurality of microlenses 11, each of which can be configured as a nanopillar. The plurality of microlenses can be embedded in the fixed layer 30. The fixed layer 30 can be made of polydimethylsiloxane or photoresist, and the metalens 10 can be made of a transparent dielectric material. The fixed layer 30 is spin-coated on the side of the microlens 11 away from the optoelectronic device 20, allowing the fixed layer 30 to penetrate between two adjacent microlenses 11.

[0084] In other words, if Figures 2 to 4As shown, the metalens 10 can be provided with a fixed layer 30. This fixed layer 30 provides dust protection, eliminating the need for a cover plate, further reducing the thickness of the polarization imaging sensor 100, lowering costs, and improving product competitiveness. The fixed layer 30 can be made of polydimethylsiloxane or photoresist, and the metalens 10 can be made of a transparent dielectric material to further improve the transmittance of the polarization imaging sensor 100.

[0085] The fixed layer 30 can be spin-coated on the side of the microlens 11 away from the optoelectronic device 20. By spin-coating polydimethylsiloxane or photoresist, it can play a dust-proof role. No cover plate is required, and the thickness of the polarization imaging sensor 100 is further reduced, thereby reducing costs and improving product competitiveness. Figure 3 At the same time, the meta-lens 10 is spin-coated with polydimethylsiloxane or photoresist. After baking and curing, the polydimethylsiloxane or photoresist penetrates into the polydimethylsiloxane or photoresist between two adjacent micro-lenses 11, which can also ensure that the micro-lenses 11 will not fall over, thereby improving the stability of the overall structure of the meta-lens 10.

[0086] According to one embodiment of the present invention, the polarization imaging sensor 100 further includes a fixed layer 30. The metalens 10 includes a plurality of microlenses 11. The microlenses 11 are fixed to one side of the fixed layer 30 and positioned between the fixed layer 30 and the optoelectronic device 20. A filling layer 40 is / are disposed between the metalens 10 and the optoelectronic device 20.

[0087] That is to say, if Figure 4 As shown, the polarization imaging sensor 100 further includes a fixed layer 30. The metalens 10 includes a plurality of microlenses 11. The microlenses 11 are disposed on one side of the fixed layer 30 and between the fixed layer 30 and the optoelectronic device 20. A filling layer 40 may also be disposed between the metalens 10 and the optoelectronic device 20.

[0088] like Figure 4 As shown, the fixed layer 30 can be made of a film material such as polydimethylsiloxane or SU-8 photoresist, which not only provides dust protection but also reduces the thickness of the polarization imaging sensor 100. The metalens 10 is made of a dielectric material. Compared to conventional linear slit metal gratings, dielectric materials have extremely low light absorption, which further improves light transmittance. The metalens 10 and the optoelectronic device 20 correspond to each other in the height direction, and a filling layer 40 is provided between the metalens 10 and the optoelectronic device 20. The filling layer 40 can be a silicon dioxide substrate, which fills the free propagation area between the lens unit and the optoelectronic device 20.

[0089] According to one embodiment of the present invention, the metalens 10 performs paraxial focusing on 0° polarized light and off-axis focusing on 90° polarized light.

[0090] In other words, in one embodiment of the present application, Figures 15 to 17 As shown, Figure 10 Curve a shows the variation of the light intensity of the first pixel with the polarization angle of the incident light, and curve b shows the variation of the light intensity of the second pixel with the polarization angle of the incident light. To verify the polarization multiplexing properties of the metalens 10, taking the second pixel as an example, the second lens unit 112 of the second pixel is designed to have a central operating wavelength of 550 nm. The nanopillars are subwavelength structural units with a height H of 480 nm and a period P of 300 nm, and are made of titanium dioxide. To achieve polarization multiplexing, a total of 64 nanopillars (subwavelength structural units) of different sizes were selected.

[0091] It should be noted that the above structural parameters and materials are selected solely to demonstrate the functionality of the embodiment and are not intended to limit the scope of protection of the present invention. The dimensions H and P of the subwavelength structural unit (nanopillar) can generally be designed to be between half the wavelength and the center operating wavelength. For example, in this embodiment, they can be designed to be 250 nm to 500 nm. Materials can be flexibly selected based on the operating wavelength. For example, in this embodiment, amorphous silicon can be used instead of titanium dioxide. Four different subwavelength structural unit sizes (32, 16, 8, and 4) can also be selected to construct the lens unit.

[0092] In this embodiment, the size of the second lens unit 112 is set to a square with a side length of 3.9 microns, and the incident light is set to a simple plane wave. Specifically, for 0° polarized light, the second lens unit 112 in the second pixel needs to achieve paraxial focusing, and the focus coordinates are set to (0, 0, 5μm). For 90° polarized light, the second lens unit 112 in the second pixel needs to achieve off-axis focusing, and the focus coordinates are set to (3.9μm, 0, 5μm). The phase distribution of the lens unit required to achieve this function is directly encoded into the structural unit at each spatial position, and the linearly polarized light directly presents this phase distribution through the propagation phase effect. The electric field distribution diagram in the xz plane obtained from the simulation calculation (see Figure 16 and Figure 17 ), it can be clearly observed from the figure that the second lens unit 112 achieves paraxial focusing for 0° polarized light and off-axis focusing for 90° polarized light.

[0093] Likewise, in another embodiment of the present application, Figure 18 and Figure 19As shown, taking the second lens unit 112 in the second pixel as an example, in order to verify the polarization multiplexing characteristics described in this embodiment, that is, to achieve paraxial focusing of 0° polarized light, the focus coordinates are set to (0, 0, 5μm). At the same time, off-axis focusing along the diagonal direction is achieved for 90° polarized light, and the focus coordinates are set to (3.9μm, 3.9μm, 5μm). The figure shows the focusing results of 0° and 90° polarized light after passing through the second lens unit 112 on the target focal plane z=5μm. It can be observed from the simulation results that 0° polarized light is focused at the center of the image plane, achieving the effect of paraxial focusing. At the same time, 90° polarized light is focused at a position with coordinates (3.9μm, 3.9μm, 5μm), achieving off-axis focusing along the diagonal direction.

[0094] In summary, the polarization imaging sensor 100 according to an embodiment of the present invention utilizes the optoelectronic device 20 and metalens 10, replacing the polarization filter. The metalens 10 vector-decomposes the converged light beams with different polarization angles. The decomposed light beams are then fully focused onto the optoelectronic device 20, effectively improving the transmittance while maintaining the extinction ratio of the polarization imaging sensor 100. Furthermore, the polarization imaging sensor 100 of this application is thinner overall, making assembly easier.

[0095] According to a second aspect of the present application, an electronic device is provided, comprising the polarization imaging sensor 100 of the above-described embodiment. Since the polarization imaging sensor 100 according to the embodiment of the present invention has the above-described technical effects, the electronic device according to the embodiment of the present invention should also have corresponding technical effects. That is, by employing the polarization imaging sensor 100, the electronic device of the present application can effectively balance extinction ratio and transmittance while also reducing thickness and dimensions, thereby improving the user experience.

[0096] Of course, for those skilled in the art, other structures and working principles of the electronic device are understandable and achievable, and will not be described in detail in this application.

[0097] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0098] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A polarization imaging sensor, characterized in that: include: A metalens, wherein the metalens decomposes a first incident light vector into a first polarization state light and a second polarization state light, wherein the polarization angle of the first polarization state light is different from the polarization angle of the second polarization state light; The optoelectronic device comprises a first optoelectronic unit and a second optoelectronic unit, wherein the light of the first polarization state is incident on the first optoelectronic unit and the light of the second polarization state is incident on the second optoelectronic unit; The metalens includes a first lens unit and a second lens unit, wherein the first lens unit is arranged opposite to the first photoelectric unit, and the second lens unit is arranged opposite to the second photoelectric unit. The first lens unit and the second lens unit each include a plurality of microlenses, and the plurality of microlenses in the second lens unit are deflected by a first angle relative to the microlenses at corresponding positions in the first lens unit. The difference between the polarization angles of the first polarization state light and the polarization angles of the second polarization state light is equal to the first angle.

2. The polarization imaging sensor according to claim 1, wherein: A second incident light passes through the metalens and is incident on the first photoelectric unit, wherein the polarization angle of the second incident light is the same as the polarization angle of the first polarized light, and the polarization angle of the second incident light is different from the polarization angle of the first incident light; The first photoelectric unit receives and records the first polarization state light obtained by decomposing the first incident light after passing through the meta-lens and the second incident light after passing through the meta-lens.

3. The polarization imaging sensor according to claim 1, wherein: The meta-lens includes a plurality of micro-lenses, and the lengths, widths, heights or side extension directions of the plurality of micro-lenses are different.

4. The polarization imaging sensor according to claim 1, wherein: The meta-lens includes a first lens unit and a second lens unit, wherein the first lens unit is arranged opposite to the first photoelectric unit, and the second lens unit is arranged opposite to the second photoelectric unit. The first lens unit and the second lens unit each include a plurality of microlenses, and each of the microlenses in the second lens unit is rotated by the same angle relative to its own axis as each of the microlenses in the first lens unit.

5. The polarization imaging sensor according to claim 1, wherein: The first lens unit and the second lens unit are distributed diagonally, and the plurality of microlenses in the first lens unit and the second lens unit are respectively distributed in an array, and the microlenses in the nth row and mth column of the first lens unit are rotated by the first angle relative to the microlenses in the nth row and mth column of the second lens unit, where n≥1 and m≥1.

6. The polarization imaging sensor according to claim 1, wherein: The meta-lens includes a first lens unit, a second lens unit, a third lens unit, and a fourth lens unit, wherein the first lens unit, the second lens unit, the third lens unit, and the fourth lens unit each include a plurality of micro lenses; The plurality of microlenses in the first lens unit, the second lens unit, the third lens unit, and the fourth lens unit are respectively distributed in an array, and the first lens unit and the fourth lens unit are arranged diagonally, and the first lens unit and the second lens unit are arranged in a horizontal direction; The microlens in the nth row and mth column of the first lens unit is rotated 90° relative to the microlens in the nth row and mth column of the second lens unit, the microlens in the nth row and mth column of the third lens unit is rotated 90° relative to the microlens in the nth row and mth column of the fourth lens unit, and the microlens in the nth row and mth column of the third lens unit is rotated 45° relative to the microlens in the nth row and mth column of the first lens unit, where n≥1 and m≥1.

7. The polarization imaging sensor according to claim 1, wherein: The meta-lens includes a first lens unit, a second lens unit, a third lens unit, and a fourth lens unit, wherein the first lens unit, the second lens unit, the third lens unit, and the fourth lens unit each include a plurality of micro lenses; The plurality of microlenses in the first lens unit, the second lens unit, the third lens unit, and the fourth lens unit are respectively distributed in an array, and the first lens unit and the second lens unit are arranged diagonally, and the first lens unit and the third lens unit are arranged in a horizontal direction; The microlens in the nth row and mth column of the first lens unit is rotated 45° relative to the microlens in the nth row and mth column of the third lens unit, the microlens in the nth row and mth column of the fourth lens unit is rotated 45° relative to the axis of the microlens in the nth row and mth column of the second lens unit, and the microlens in the nth row and mth column of the fourth lens unit is rotated 135° relative to the microlens in the nth row and mth column of the first lens unit, where n≥1 and m≥1.

8. The polarization imaging sensor according to any one of claims 6 or 7, characterized in that: The optoelectronic device further includes a third optoelectronic unit and a fourth optoelectronic unit, the first lens unit is arranged opposite to the first optoelectronic unit, the second lens unit is arranged opposite to the second optoelectronic unit, the third lens unit is arranged opposite to the third optoelectronic unit, and the fourth lens unit is arranged opposite to the fourth optoelectronic unit; The meta-lens decomposes the first incident light into a first polarization state light, a second polarization state light, a third polarization state light, and a fourth polarization state light, wherein the polarization angle of the first polarization state light is 0°, the polarization angle of the second polarization state light is 90°, the polarization angle of the third polarization state light is 45°, and the polarization angle of the fourth polarization state light is 135°; The third polarization state light is incident on the third photoelectric unit, and the fourth polarization state light is incident on the fourth photoelectric unit.

9. The polarization imaging sensor according to claim 1, wherein: Also includes: A fixed layer, the meta-lens includes a plurality of micro-lenses, and the plurality of micro-lenses are embedded in the fixed layer.

10. The polarization imaging sensor according to claim 9, characterized in that: The fixed layer is polydimethylsiloxane or photoresist, and the meta-lens is a transparent dielectric material; wherein the fixed layer is spin-coated on a side of the micro-lens away from the optoelectronic device, so that the fixed layer can penetrate between two adjacent micro-lenses.

11. The polarization imaging sensor according to claim 1, wherein: It also includes a fixed layer, the meta-lens includes a plurality of micro-lenses, the micro-lenses are fixed on one side of the fixed layer, and the micro-lenses are located between the fixed layer and the optoelectronic device; and / or A filling layer is provided between the metalens and the optoelectronic device.

12. The polarization imaging sensor according to claim 1, wherein: The meta-lens performs paraxial focusing on 0° polarized light and off-axis focusing on 90° polarized light.

13. An electronic device, characterized in that: The polarization imaging sensor comprises the polarization imaging sensor according to any one of claims 1 to 12.

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