Lens array and preparation method thereof, and naked-eye 3D implementation method

Abstract

The invention provides a lens array, a preparation method thereof and a naked-eye 3D implementation method, and relates to the technical field of naked-eye 3D. The lens array comprises a substrate and a nano unit, the nanometer unit is generated on the substrate; the nano units are arranged periodically; the diameters and / or heights of the nano units continuously change along with the positions of the nano units in the array; wherein the nano units approximately realize the same phase modulation distribution under red light, green light and blue light. Broadband achromatism is achieved through the nanostructure, it is ensured that red light, green light and blue light are imaged on the same focus, the chromatic aberration problem of a traditional micro lens is fundamentally solved, and the color effect of a 3D image is greatly improved. The stray light eliminating function is achieved through the precise design of the nano structure, it is guaranteed that only light within a certain angle range penetrates, and the definition of a 3D image is greatly improved.

Description

Technical Field

[0001] This application relates to the field of naked-eye 3D technology, and more specifically, to a lens array, a method for fabricating the array, and a method for realizing naked-eye 3D. Background Technology

[0002] First, in microlens array-based moiré imaging systems, only transmissive structures can be used to generate floating real images in order to achieve regional imaging of flat panel displays. This structure imposes strict constraints on the relative periodicity of the microlenses and micropatterns, and typically requires maintaining a fixed relative position and alignment accuracy, limiting the system's application flexibility in complex scenes or dynamic displays. Furthermore, transmissive imaging often depends on specific lighting conditions, and ambient light interference can lead to decreased imaging contrast or weakened visual effects.

[0003] Secondly, although metasurface lenses can achieve thin, planar optical designs by controlling the phase and amplitude of light at the subwavelength scale, and overcome the volume and aberration limitations of traditional curved lenses, they still face several challenges in practical applications. For example, the fabrication of metasurface lenses typically relies on nanofabrication technology, which requires extremely high process precision, leading to increased manufacturing costs and difficulties in large-scale production. Simultaneously, maintaining chromatic aberration correction and efficiency across a wide wavelength range still presents challenges in terms of design complexity and performance trade-offs. Furthermore, the design and optimization of existing metasurface lenses are often targeted at specific functions or single wavelengths, making it difficult to simultaneously achieve high efficiency and high imaging quality in continuous spectrum or multi-wavelength composite scenarios, thus limiting their direct application in full-color displays and composite imaging systems. Summary of the Invention

[0004] In view of this, the purpose of this application is to provide a lens array and its preparation method, as well as a method for realizing naked-eye 3D, so as to improve the above-mentioned problems existing in the prior art.

[0005] In a first aspect, embodiments of this application provide a lens array, the lens array comprising: a substrate and nanounits; the nanounits are generated on the substrate; the nanounits are arranged periodically; the diameter and / or height of the nanounits continuously vary with their position in the array; wherein the nanounits approximately achieve the same phase modulation distribution under red, green, and blue light.

[0006] In the above implementation process, by continuously varying the diameter and / or height of the nanounits with their position, spatial phase modulation of incident light at different positions in the array is achieved. Since the structural parameters change continuously rather than abruptly, the dispersion effect is effectively reduced, enabling the lens array to achieve approximately consistent phase modulation distribution under illumination in the red, green, and blue light bands. This significantly reduces chromatic aberration and achieves broadband achromatic imaging.

[0007] Optionally, the material of the nanounit includes one or more of titanium dioxide, silicon nitride, or zinc sulfide. In the above-mentioned process, high refractive index materials can significantly enhance the scattering ability of nanounits on incident light, thereby achieving subwavelength scale. These materials provide complete phase coverage across the entire range; simultaneously, they exhibit extremely low absorption loss in the visible to near-infrared bands, ensuring a high level of transmission efficiency for the lens array. Furthermore, they possess excellent thermal and chemical stability, making them suitable for long-term stable operation under high-power illumination and complex environmental conditions.

[0008] Optionally, the shape of the nanounit includes one or more of spheres, cylinders, or elliptical cylinders.

[0009] In the above implementation process, by selecting nano-units with different geometric shapes, the weights of the resonance mode and geometric phase contribution can be independently adjusted while keeping the period unchanged, so that the phase modulation curve remains linear and has a consistent slope over a wide band. The Mie resonance introduced by the spherical unit can expand the phase control margin, the cylindrical unit provides high symmetry to reduce polarization sensitivity, and the elliptical cylindrical unit uses anisotropy to break degeneracy, and can still maintain the phase distribution consistency of red, green and blue light in oblique incidence or wide field of view, thus taking into account both achromatic performance and process tolerance.

[0010] Optionally, the nanounit is elliptical in shape, with a diameter ranging from 100 nm to 400 nm and a height ranging from 500 nm to 800 nm.

[0011] In the above implementation process, the simultaneous scanning of the major and minor axes of the elliptical cylinder allows for continuous gradual changes in the structural parameters across the entire field of view within a single exposure and etching process, eliminating the need for multi-layer overlay etching. This simplifies the process and ensures good repeatability. The diameter variation range of 100 nm to 400 nm covers the overlap region of electric and magnetic dipole resonances, providing a single-step process. The smooth phase modulation, along with the consistent slope of the effective refractive index dispersion curves across the three fundamental wavelengths within the 500 nm to 800 nm height range, ensures that the phase errors of red, green, and blue light are all less than [value missing]. This enables the mass production of monolithic broadband achromatic plane lenses.

[0012] Optionally, the material of the substrate includes one or more of the following: quartz glass, sapphire, fused silica, or high refractive index glass.

[0013] In the above process, the high light transmittance and wide band consistency of the substrate material can suppress background reflection, ensure that the phase modulation signal of the nanounit is dominant, and enable the lens array to exhibit stable and repeatable focusing characteristics under red, green and blue illumination.

[0014] In a second aspect, a method for fabricating a lens array includes: forming a dielectric thin film on a substrate and defining a nano-unit array pattern on the dielectric thin film; etching the dielectric thin film using the nano-unit array pattern as a mask to form the nano-unit array; and removing residual mask material to obtain the lens array described above.

[0015] In the above process, the fabrication of high aspect ratio nanoarrays is completed without the need for multi-layer alignment or metal stripping, which simplifies the process chain and avoids phase noise caused by overlay errors. At the same time, the integrated design of the mask and the layer to be etched makes the sidewall steepness better than 80°, ensuring the lateral gradient accuracy of the geometric parameters of the elliptical cylinder. This ensures that the red, green and blue light obtains consistent phase modulation on the entire lens, realizing wafer-level, low-cost, and highly repeatable mass production of broadband achromatic plane lenses.

[0016] Thirdly, a method for realizing naked-eye 3D, the method comprising: acquiring two-dimensional image data corresponding to a target three-dimensional image; performing patterning processing on the two-dimensional image data to obtain a micro-pattern array; wherein the patterning processing spatially redistributes the image content based on a preset period; modulating the light of the micro-pattern array based on an optical modulator to generate a naked-eye three-dimensional visual image; wherein the optical modulator includes the lens array described above, and the optical modulator has a modulation period matching the preset period.

[0017] In the aforementioned implementation process, the broadband achromatic properties of the lens array ensure that the light rays from the red, green, and blue sub-pixels maintain spatial phase consistency after passing through the same modulation cycle, avoiding color shift and crosstalk. Its nano-unit parameters continuously and gradually change with position, enabling simultaneous viewpoint segmentation and wavefront reconstruction within a single plane, eliminating the need for additional diffusion films or cylindrical mirrors, and reducing the system thickness to the hundreds of micrometers level. Thus, after passing through an optical modulator, the beams from each viewpoint of the micro-pattern array are collimated and incident directly into the human eye, with the left and right eyes receiving independent parallax images. This achieves full-color, low stray light, and wide field-of-view naked-eye 3D display, with a large tolerance for viewing distance and angle, adapting to the thinner and lighter requirements of mobile display terminals.

[0018] Optionally, the patterning process includes: extracting corresponding local image fragments from the two-dimensional image data as micro-patterns according to the periodic units defined by the preset period, and setting the micro-patterns at the positions of the corresponding periodic units.

[0019] In the above implementation process, the two-dimensional image data is directly split into local segments corresponding to the lens units by using a preset period as the sampling grid. No additional interpolation or compression is required. This not only preserves the original parallax information, but also makes the micro-pattern naturally aligned with the modulation period of the subsequent lens array. This simplifies the data generation process and reduces the risk of moiré patterns and ghosting caused by pixel mismatch.

[0020] Optionally, the step of modulating the light of the micro-pattern array based on the optical modulator to generate a naked-eye three-dimensional visual image includes: displaying the micro-pattern array on a flat panel display screen; placing the optical modulator on the light-emitting side of the flat panel display screen, and the light emitted by the flat panel display screen passes through the optical modulator to generate a naked-eye three-dimensional visual image.

[0021] In the above implementation process, the flat panel display screen is only responsible for illuminating the micro-patterns in periodic units. The optical modulator can work by directly attaching to its light-emitting side without the need for an additional light source, collimation system or mechanical alignment mechanism. The distance between the nanostructure layer of the lens array and the screen surface is controlled at the level of hundreds of micrometers, so that the beams of light from different angles are immediately given a preset phase after exiting the screen, forming spatially separated viewpoints. Viewers can receive continuous parallax within the normal viewing distance.

[0022] Optionally, the light emitted by the flat panel display screen passes through the optical modulator, including: providing transmission conforming to the target phase modulation for incident light with an incident angle less than or equal to a first angle threshold; and providing transmission deviating from the target phase modulation for incident light with an incident angle greater than the first angle threshold.

[0023] In the above implementation process, the lens array maintains a linear phase response at small angles of incidence through a continuously gradient nanoelliptical cylinder structure, so that the light within the main viewing angle range is reconstructed according to the designed wavefront, ensuring the brightness and depth accuracy of the 3D image; when the incident angle exceeds the first angle threshold, the phase curve becomes nonlinear, the transmitted light deliberately deviates from the target modulation, and the energy is dispersed to higher-order diffraction or background, thereby suppressing large-angle stray light and crosstalk between adjacent viewpoints, improving the contrast and viewing angle purity of naked-eye 3D display, and achieving natural separation of private and public areas without the need for an additional privacy film.

[0024] This application also provides an electronic device, which includes a memory and a processor. The memory stores program instructions, and when the processor reads and runs the program instructions, it executes the steps in any of the above implementation methods.

[0025] This application also provides a computer-readable storage medium storing computer program instructions, which are read and executed by a processor to perform the steps in any of the above implementations. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of a lens array provided in an embodiment of this application; Figure 2 Statistical diagrams of nanostructure dimensions provided for embodiments of this application; Figure 3 A simplified schematic diagram of the system provided in this application embodiment; Figure 4 This is a schematic diagram of the phase distribution of each wavelength provided in the embodiments of this application; Figure 5 This is a flowchart illustrating the method for fabricating a lens array as provided in an embodiment of this application. Figure 6 The method for implementing naked-eye 3D provided in the embodiments of this application; Figure 7 This is a block diagram of an electronic device provided in an embodiment of this application.

[0028] Icons: 001-Substrate; 002-Nano unit; 003-Display; 100-Electronic device; 111-Memory; 112-Memory controller; 113-Processor; 114-Peripheral interface; 115-Input / output unit; 116-Display unit. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of the embodiments of this application.

[0030] Moiré imaging can be achieved by superimposing a microlens array with a designed micropattern array in a certain manner. Moiré imaging has a real / virtual effect: when the period of the microlens array is less than the period of the micropattern array, the moiré image is above the microlens and forms a real image; when the period of the microlens array is greater than the period of the micropattern array, the moiré image is below the micropattern and forms a virtual image. Moiré imaging has transmissive and reflective types. In reflective type, the micropattern is above the microlens, and in transmissive type, the micropattern is below the microlens. Since imaging of an area of ​​the flat panel display 003 is required, only a transmissive structure can be selected to form a floating real image.

[0031] Traditional optical lenses rely on light propagating over distances much larger than the wavelength to form wavefronts. The properties of light change cumulatively over the distance traveled, leading to the need for large sizes and curved surface configurations in traditional optical elements. Metasurfaces, on the other hand, allow for the free design of optical wavefronts within the wavelength scale, overcoming the limitations of traditional optical element design. By designing the interaction between the incident light and nanoscale units, metalenses can achieve precise control of the outgoing light beam. By changing the size and structure of the metalens, the phase and transmittance of the outgoing light at different positions can be adjusted, thereby controlling the magnitude and direction of the outgoing light.

[0032] Firstly, please refer to Figure 1 , Figure 1 This is a schematic diagram of a lens array provided in an embodiment of this application.

[0033] This application provides a lens array, which includes a substrate 001 and nano-units 002; nano-units 002 are generated on the substrate 001; the nano-units 002 are arranged periodically; the diameter and / or height of the nano-units change continuously with their position in the array; wherein the nano-units 002 approximately achieve the same phase modulation distribution under red, green and blue light.

[0034] In the aforementioned implementation process, by optimizing the geometric parameters of the nanounit 002, it is possible to achieve approximately the same phase response in the red, green, and blue light bands. This enables consistent wavefront modulation over a wide wavelength range, reducing chromatic aberration and improving imaging or beam shaping effects across multiple wavelengths. By achieving approximately the same phase modulation in red, green, and blue light, the lens array can significantly reduce dispersion problems and avoid shifts in the focusing position of light of different wavelengths. The diameter and / or height of the nanounit 002 continuously vary with position, allowing for fine-tuning of the incident light phase. The periodic arrangement of the nanounits 002 and their continuous parameter changes make them suitable for wafer-level mass production using semiconductor processes (such as nanoimprinting and photolithography). Optical elements based on nanostructures typically exhibit high transmittance and low absorption loss, and phase modulation is achieved through geometric phase or resonant phase modulation, resulting in high efficiency.

[0035] In one embodiment of this application, the core performance indicators of the superlens need to be defined based on the application requirements of the target optical system. Key parameters typically include: focal length, for example... =500μm, which determines the lens's converging ability and the position of the imaging plane; the working wavelength, for example, is selected. =386 nm, 588 nm and 656 nm three characteristic spectral lines to cover the visible light band; and stray light suppression requirements, such as setting the main lobe outer The energy suppression ratio within a certain range is used to control sidelobes and improve image contrast. Based on these parameters, the coordinates of any point on the lens plane can be calculated using optical path difference theory. The phase delay distribution required to achieve ideal focusing The calculated continuous spatial phase distribution This is discretized and mapped onto an array of nanounits 002 of different sizes. To do this, it is necessary to establish the geometric parameters (D, H) of the nanostructure and their resulting transmission phase. A database of correspondences between amplitude T and other parameters is established. The creation of this database relies on rigorous electromagnetic field simulation calculations. Methods such as Finite-Difference Time-Domain (FDTD) or Rigorous Coupled-Wave Analysis (RCWA) are typically used to perform scanning simulations of unit structures under periodic boundary conditions. The simulation outputs the transmission phase and transmittance for various size combinations, and further evaluates its collimation efficiency (i.e., the proportion of light energy emitted in the design direction). Through optimized design, while ensuring complete phase coverage... While maintaining the cycle, we strive for consistency and high efficiency in the transmission amplitude of each unit.

[0036] Optionally, the material of the nanounit 002 includes one or more of titanium dioxide, silicon nitride, or zinc sulfide. In the above implementation process, the physical basis for achieving continuous phase modulation is the periodically arranged subwavelength nanostructure units. The choice of materials is crucial, requiring high refractive index and low optical loss to achieve high efficiency. The aforementioned materials possess significantly higher refractive indices in the visible to near-infrared band than air and common substrates (such as silicon dioxide), while exhibiting extremely low absorption loss. The high refractive index ensures that light waves generate strong localized field resonance and sufficient phase delay within and around the nanounits (002), enabling the realization of 0 to 1 phase delay using subwavelength thickness structures. Full phase coverage becomes possible; low loss directly ensures that the device has high transmission efficiency and reduces light energy waste.

[0037] In one embodiment of this application, titanium dioxide ( For example, it has a high refractive index in the visible light band. With its extremely low extinction coefficient, nanostructures enable efficient modulation of the light wave phase while avoiding significant energy absorption. These nanostructures are typically cylindrical or rectangular, and by precisely controlling their lateral dimensions (e.g., diameter D varying from 100 nm to 400 nm) and height H (e.g., 500 nm to 800 nm), coverage of wavelengths from 0 to 100 nm can be achieved at a single wavelength. The transmission phase response.

[0038] Optionally, the shape of the nanounit 002 includes one or more of the following: spherical, cylindrical, or elliptical.

[0039] In the aforementioned implementation process, rotationally symmetric structures such as cylinders are typically used to control phase independent of polarization. Asymmetric structures such as elliptical cylinders, due to their anisotropy, can produce differentiated optical responses to light with different polarization directions, thus laying the foundation for designing polarization-sensitive or polarization-converting metasurface lenses (such as those for achieving bifocal distances and polarization beam splitting). Different shapes determine the characteristics of their electromagnetic resonance modes (such as Mie resonances). By optimizing specific shapes (and their orientations) through simulation, phase, amplitude, and polarization responses can be more precisely adjusted, contributing to higher transmission efficiency, more accurate phase control, and better achromatic effects across a wide wavelength range.

[0040] Optionally, the shape of the nanounit 002 is an elliptical cylinder, the diameter of the nanounit 002 is in the range of 100nm to 400nm, and the height is in the range of 500nm to 800nm.

[0041] In the aforementioned implementation process, unlike rotationally symmetric cylinders, elliptical cylinders have different dimensions in two orthogonal directions (major and minor axes). When linearly polarized light is incident, its electric field components experience different effective refractive indices and resonant characteristics along different axes, resulting in differentiated phase delays. Elliptical cylinders have an additional adjustable dimension (major-minor axis ratio) compared to cylinders. In rigorous electromagnetic simulations (such as FDTD), by simultaneously scanning the major axis, minor axis, and height, a set of nanounit 002 size combinations that can produce approximate phase responses for the three target wavelengths of red, green, and blue can be found within a vast design space.

[0042] Please see Figure 2 , Figure 2 A statistical chart of nanostructure dimensions provided for embodiments of this application.

[0043] For diameters ranging from 100 to 400 nm, the lower limit is 100 nm to ensure a sufficiently small structure size to allow for effective electromagnetic interaction with incident light (visible light wavelengths of approximately 400 to 700 nm), while avoiding fabrication limitations and mechanical fragility caused by excessively small unit sizes. The upper limit of 400 nm ensures the unit remains in the subwavelength region, below the shortest operating wavelength, such as blue light up to 450 nm, to suppress higher-order diffraction and ensure the device operates in metasurface mode, with the main energy concentrated in zero-order transmission. Simultaneously, this range is sufficient to achieve complete zero-to-high wavelength transmission within the target band by exciting different Mie resonance modes. Phase modulation.

[0044] For heights ranging from 500 to 800 nm, sufficient height provides enough optical path for light waves to propagate inside and around the nanostructure in order to accumulate the required phase difference. The height of 500 to 800 nm is comparable to the wavelength of visible light, which is a necessary condition for achieving strong phase modulation. It can also ensure performance while taking into account structural uprightness, avoiding the collapse of high aspect ratio structures and improving fabrication efficiency.

[0045] Optionally, the material of the substrate 001 includes one or more of the following: quartz glass, sapphire, fused silica, or high refractive index glass.

[0046] In the aforementioned implementation process, the listed materials exhibit extremely high optical transparency and extremely low absorption and scattering losses in the visible to near-infrared bands. This ensures that incident light can pass through the substrate 001 to the functional nanounit 002 layer with maximum lossless penetration, and that transmitted light can exit efficiently, which is a fundamental prerequisite for achieving high optical efficiency in the entire lens array. When selecting the substrate 001 material, the compatibility of its thermal expansion coefficient with the upper nanounit 002 material (such as titanium dioxide or silicon nitride) is considered. Good compatibility can reduce thermal stress caused by changes in process temperature or fluctuations in the operating environment temperature, prevent structural delamination or cracking, and improve device reliability. Furthermore, the surfaces of these substrate 001 materials are easy to clean and activate, and can form a robust, low-defect interface with the functional material film, which is crucial for achieving a high-quality, uniform nanounit 002 array.

[0047] In one embodiment of this application, please refer to Figure 3 , Figure 3 A simplified schematic diagram of the system provided in this application embodiment.

[0048] Please also refer to Figure 4 , Figure 4 This is a schematic diagram of the phase distribution of each wavelength provided in the embodiments of this application.

[0049] A point light source is placed at a distance f in front of the lens (i.e., at the focal point). The light it emits is a spherical diverging wave. The lens converts this wave into a plane wave propagating along the Z-axis. The phase delay required at any point (x, y, 0) on the lens surface is:

[0050] For the three wavelengths of light emitted by the flat panel display 003, the phase delay of each wavelength is:

[0051]

[0052]

[0053] in These represent the wavelengths of red, green, and blue light, respectively. Achromatic light requires that the lens produces the same phase delay for light of different wavelengths; therefore:

[0054] If a phase distribution can be found that simultaneously approximates the desired ideal phase at each of the three wavelengths (RGB), then color difference can be eliminated.

[0055] Suppressing stray light requires, on the basis of achromaticity, ensuring that the phase profile of the metalens precisely satisfies the achromatic condition only for light rays incident at small angles. When light is incident at large angles, a large wavefront aberration is introduced, making it impossible to collimate and resulting in scattered light with extremely large divergence angles, low brightness, and irregular patterns. In the design, we can optimize the structure of the nanounit 002 to make it angle-sensitive. The objective function for stray light suppression can be expressed as:

[0056] in, It's about collimation efficiency. It is a weighting factor that controls the degree of suppression of stray light. At small angles... When at large angles It decreases until it approaches 0.

[0057] Through this optimization, the algorithm automatically finds a nanostructure arrangement that focuses only on the focal direction angle. The light rays have the correct phase response.

[0058] Secondly, please refer to Figure 5 , Figure 5 This is a flowchart illustrating the fabrication method of the lens array provided in an embodiment of this application.

[0059] A method for fabricating a lens array includes: forming a dielectric thin film on a substrate 001 and defining a nano-unit 002 array pattern on the dielectric thin film; etching the dielectric thin film using the nano-unit 002 array pattern as a mask to form a nano-unit 002 array; and removing residual mask material to obtain the lens array.

[0060] In the above process, high-transmittance quartz glass is used as the substrate (001). A titanium dioxide thin film is grown on the substrate using atomic layer deposition or magnetron sputtering techniques. The film thickness is determined by the output parameters. An electron beam photoresist layer is coated on the film surface. Using a high-precision electron beam lithography system, a focused electron beam is used to expose the photoresist point-by-point according to the output parameters, writing the pattern of the nanopillar array into the photoresist layer. After exposure, the sample is placed in a developer to dissolve the photoresist in the exposed areas. Using the photoresist as a mask, the pattern is precisely transferred to the underlying titanium dioxide thin film, with the etching depth equal to the film thickness. After etching, residual photoresist is removed with a solvent, exposing the titanium dioxide nanopillar array. Finally, the shape, size, and alignment accuracy of the nanopillars are examined using a scanning electron microscope, and their optical properties are tested.

[0061] Specifically, in this embodiment, during the manufacturing process, high optical transmittance and low autofluorescence quartz glass is first selected as the substrate material. Its excellent chemical and thermal stability provides an ideal platform for the subsequent fabrication of nanostructures. Subsequently, a uniform and dense titanium dioxide film is grown on the clean substrate surface using atomic layer deposition (ALD) or magnetron sputtering. The thickness of the film needs to be precisely controlled according to the optical design parameters of the final device, typically in the range of tens to hundreds of nanometers, to meet the phase modulation or resonance requirements within a specific wavelength range. Next, a high-resolution photoresist (such as PMMA) sensitive to electron beams is spin-coated onto the surface of the titanium dioxide film. Using a high-precision electron beam lithography system, according to the preset nanopillar array pattern (including diameter, period, and arrangement), the photoresist is selectively exposed by a focused electron beam, writing the designed nanostructure point by point into the photoresist layer. Exposure parameters such as dose, beam current, and scan step size need to be optimized according to the characteristics of the photoresist and the required pattern size. After exposure, the sample is treated in a specific developer to dissolve the photoresist layer in the electron beam-exposed areas, thus forming a hollow pattern of a nanopillar array within the photoresist. Subsequently, using the photoresist pattern as a mask, reactive ion etching (RIE) or ion beam etching (IBE) techniques are employed to precisely transfer the pattern to the underlying titanium dioxide film. The etching process requires strict control of time and process parameters to ensure complete penetration of the film while maintaining sidewall perpendicularity and pattern fidelity. After etching, the residual photoresist mask is thoroughly removed using an appropriate solvent (such as acetone or a dedicated photoresist remover), exposing the completely independent titanium dioxide nanopillar array. Finally, the array's morphology is characterized using scanning electron microscopy to check whether the diameter, height, sidewall morphology, and arrangement period of the nanounits meet the design requirements. In addition, it is necessary to use a spectral measurement system (such as a microspectrometer or Fourier transform infrared spectrometer) to test its transmission, reflection or absorption spectra and evaluate its optical performance in the target band, such as anomalous transmission, structural color or phase modulation ability, in order to verify the reliability of the preparation process and the functionality of the nanostructure.

[0062] Thirdly, please refer to Figure 6 , Figure 6 This application provides a method for implementing glasses-free 3D.

[0063] A method for realizing naked-eye 3D includes: acquiring two-dimensional image data corresponding to a target three-dimensional image; performing patterning processing on the two-dimensional image data to obtain a micro-pattern array; wherein the patterning processing spatially redistributes the image content based on a preset period; and modulating the light of the micro-pattern array based on an optical modulator to generate a naked-eye three-dimensional visual image; wherein the optical modulator includes the aforementioned lens array and has a modulation period that matches the preset period.

[0064] Optionally, the patterning process includes: extracting corresponding local image fragments from the two-dimensional image data as micro-patterns according to the periodic units defined by a preset period, and setting the micro-patterns at the positions of the corresponding periodic units.

[0065] In the above implementation process, patterning can be optimized by using virtual masking technology to design the micro-pattern array. Virtual masking technology is an array processing method based on the positional distribution and shape design of micro-patterns, which can break through the limitations of the microlens array period in terms of the size of a single micro-pattern and improve imaging resolution.

[0066] Specifically, the virtual masking technology includes: constructing a virtual mask pattern corresponding to a periodic unit of the microlens array, wherein the size and position distribution of the mask are aligned with each periodic unit of the microlens array; and locally preserving and cropping the micro-pattern based on the virtual mask, wherein the microlens array has a distribution coordinate matrix. The micropattern array has a distributed coordinate matrix The virtual mask has a graphical coordinate matrix. Based on the graphical coordinate matrix of the virtual mask The micro-patterns are cropped and then repositioned to their corresponding positions in the micro-pattern coordinate matrix, resulting in a micro-pattern array processed by a virtual mask. Through this method, the virtual mask technology achieves a finer distribution of micro-patterns during patterning, allowing for a more precise match with the modulation period of the optical modulator, thereby improving the visual resolution and stereoscopic effect of the naked-eye 3D image.

[0067] Optionally, generating a naked-eye three-dimensional visual image by modulating the light of the micro-pattern array based on an optical modulator includes: displaying the micro-pattern array on a flat panel display screen 003; setting the optical modulator on the light-emitting side of the flat panel display screen 003, and the light emitted by the flat panel display screen 003 passing through the optical modulator to generate a naked-eye three-dimensional visual image.

[0068] In one embodiment of this application, a micro-pattern array processed by a virtual mask can be displayed on a flat panel display 003 via backend computer control. The flat panel display 003 should be placed at the focal plane of the optical modulator. The light emitted by the display, containing red, green, and blue light spectra, is collimated into parallel light after passing through a metalens array and then enters the human eye to form an image. During this process, the periodic structure of the metalens array and the periodic arrangement of the pixel array of the display 003 superimpose each other to produce a moiré fringe optical effect, thereby achieving a naked-eye 3D visual effect. Furthermore, by adjusting the brightness and color of each pixel unit on the flat panel display 003 in real time, the display of dynamic three-dimensional images can be further realized.

[0069] Optionally, the light emitted by the flat panel display 003 passes through an optical modulator, including: providing transmission conforming to the target phase modulation for incident light with an incident angle less than or equal to a first angle threshold; and providing transmission deviating from the target phase modulation for incident light with an incident angle greater than the first angle threshold.

[0070] In one embodiment of this application, the object is The nanopillars of the material have adjustable structural parameters limited to a height of 500 to 800 nm, a diameter of 100 to 400 nm, and a fixed period of 500 nm; the corresponding optical conditions for optimization are determined, including the operating wavelength (486 nm, 588 nm, 656 nm) and the angle threshold (…). ), and the system focal length (500) Regarding the angle. In the scenario, calculate the coverage area. The signal gain (three wavelengths) was evaluated to assess its collimation effect; for angle... In this scenario, the noise suppression capability within the specified range (also covering three wavelengths) is calculated, and its stray light suppression effect is evaluated. If the current collimation and suppression effects do not meet the preset target (i.e., not converged), a parameter adjustment mechanism is initiated. The height, diameter, and other parameters of the nanopillar are optimized using a genetic algorithm, while a stochastic algorithm is used to avoid getting trapped in local optima. After adjustment, the performance evaluation and calculation are repeated, and the next iteration begins. If the effect meets the target (i.e., converged), the process ends, and the final nanopillar design parameters (including specific values ​​such as height and diameter) are output.

[0071] Optionally, please refer to Figure 7 , Figure 7 This is a block diagram illustrating an electronic device according to an embodiment of this application. The electronic device 100 may include a memory 111, a memory controller 112, a processor 113, a peripheral interface 114, an input / output unit 115, and a display unit 116. Those skilled in the art will understand that... Figure 7 The structure shown is for illustrative purposes only and does not limit the structure of the electronic device 100. For example, the electronic device 100 may also include components that are more... Figure 7 The more or fewer components shown, or having the same Figure 7 The different configurations shown.

[0072] The aforementioned memory 111, memory controller 112, processor 113, peripheral interface 114, input / output unit 115, and display unit 116 are electrically connected directly or indirectly to each other to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The aforementioned processor 113 is used to execute executable modules stored in the memory.

[0073] The memory 111 can be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), etc. The memory 111 stores programs, and the processor 113 executes these programs upon receiving execution instructions. The methods executed by the electronic device 100 as defined in any embodiment of this application can be applied to the processor 113, or implemented by the processor 113.

[0074] The aforementioned processor 113 may be an integrated circuit chip with signal processing capabilities. The processor 113 may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it may also be a digital signal processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor.

[0075] The peripheral interface 114 described above couples various input / output devices to the processor 113 and the memory 111. In some embodiments, the peripheral interface 114, the processor 113, and the memory controller 112 can be implemented on a single chip. In other instances, they can be implemented on separate chips.

[0076] The input / output unit 115 described above is used to provide user input data. The input / output unit 115 may be, but is not limited to, a mouse and keyboard, etc.

[0077] The aforementioned display unit 116 provides an interactive interface (e.g., a user interface) between the electronic device 100 and the user, or displays image data for the user's reference. In this embodiment, the display unit can be a liquid crystal display (LCD) or a touch display. If it is a touch display, it can be a capacitive touchscreen or a resistive touchscreen that supports single-point and multi-point touch operations. Supporting single-point and multi-point touch operations means that the touch display can sense touch operations generated simultaneously from one or more locations on the touch display and pass the sensed touch operations to the processor for calculation and processing.

[0078] This application also provides a computer-readable storage medium storing computer program instructions, which are read and executed by a processor to perform steps in a method for implementing glasses-free 3D.

[0079] In summary, this application provides a lens array, its fabrication method, and a method for realizing naked-eye 3D, relating to the field of naked-eye 3D technology. The lens array includes a substrate and nanounits; the nanounits are generated on the substrate; the nanounits are arranged periodically; the diameter and / or height of the nanounits continuously change with their position in the array; wherein the nanounits approximately achieve the same phase modulation distribution under red, green, and blue light. By achieving broadband achromatic light through the nanostructure, red, green, and blue light are ensured to be imaged at the same focal point, fundamentally solving the chromatic aberration problem of traditional microlenses and significantly improving the color effect of 3D images. The precise design of the nanostructure achieves stray light elimination, ensuring that only light within a certain angle range is transmitted, significantly improving the clarity of 3D images.

[0080] In the several embodiments provided in this application, it should be understood that the disclosed device can also be implemented in other ways. The device embodiments described above are merely illustrative; for example, the block diagrams in the accompanying drawings illustrate the possible architecture, functions, and operations of the device according to various embodiments of this application. In this regard, each block in the block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagram, and combinations of block diagrams, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0081] In addition, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0082] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0083] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0084] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

[0085] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A lens array characterized by, The lens array comprises: a substrate and nano units; The nano units are generated on the substrate; the nano units are arranged periodically; The diameter and / or height of the nano units continuously vary with their positions in the array; The nano units approximately achieve the same phase modulation distribution under red, green and blue light.

2. The lens array of claim 1, wherein, The nano units are arranged in a periodic array. The material of the nano units comprises one or more of titanium dioxide, silicon nitride or zinc sulfide.

3. The lens array of claim 1, wherein, The nano units are arranged in a periodic array. The shape of the nano units comprises one or more of spherical, cylindrical or elliptical cylindrical.

4. The lens array of claim 3, wherein, The nano units are arranged in a periodic array. The material of the substrate comprises one or more of quartz glass, sapphire, fused quartz or high refractive index glass.

5. The lens array of claim 1, wherein, The method comprises: forming a dielectric thin film on a substrate, and defining a nano unit array pattern on the dielectric thin film; etching the dielectric thin film with the nano unit array pattern as a mask to form the nano unit array; and removing the residual mask material to obtain the lens array according to claims 1 to 5.

6. A method for producing a lens array, characterized by, The method comprises: obtaining two-dimensional image data corresponding to a target three-dimensional image; 7. A method for implementing naked-eye 3D, characterized in that, performing pattern processing on the two-dimensional image data to obtain a micro-pattern array; wherein the pattern processing is based on a pre-set period to spatially redistribute image content; modulating light of the micro-pattern array based on an optical modulator to generate a naked-eye three-dimensional visual image; wherein the optical modulator comprises the lens array according to any one of claims 1 to 5, and the optical modulator has a modulation period matching the pre-set period. The pattern processing comprises: According to the period unit defined by the pre-set period, extract the corresponding local image segment from the two-dimensional image data as a micro-pattern, and set the micro-pattern at the position of the corresponding period unit.

8. The method of claim 7, wherein, The modulation of light of the micro-pattern array based on the optical modulator to generate a naked-eye three-dimensional visual image comprises: displaying the micro-pattern array on a flat display screen; 9. The method of claim 7, wherein, setting the optical modulator on the light-emitting side of the flat display screen, and the light emitted by the flat display screen passes through the optical modulator to generate a naked-eye three-dimensional visual image. The light emitted by the flat display screen passing through the optical modulator comprises: for incident light with an incident angle less than or equal to a first angle threshold, providing transmission conforming to a target phase modulation; 10. The method of claim 9, wherein, for incident light with an incident angle greater than the first angle threshold, providing transmission deviating from the target phase modulation. ​ ​

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