A method for generating a micro image array for spatial stereoscopic imaging and an optical imaging film

Abstract

This invention discloses a method for generating micro-image arrays for spatial stereoscopic imaging and an optical imaging thin film. The method incorporates processing resolution and observation conditions as constraints during the design phase. First, it determines the achievable minimum period difference and effective imaging height range. Then, within this range, it performs a grayscale-to-height mapping, converting continuous height variations into a processable discrete periodic distribution. Simultaneously, while generating the stereoscopic height through periodic offset, a discrete scaling factor is introduced to compensate for differences in imaging magnification. This method links position adjustment and size scaling during micro-image generation, allowing the scaling to change with the discrete periodic distribution. Therefore, the image proportions of different height layers are more easily maintained closely, the distortion caused by local size inconsistencies is less pronounced, and the overall stereoscopic image's proportions and edge transitions are more natural.

Description

Technical Field

[0001] This invention relates to the field of micro-nano optical imaging technology, specifically to a method for generating micro-image arrays for spatial stereo imaging and an optical imaging thin film. Background Technology

[0002] Microlens array spatial imaging technology is a novel naked-eye 3D display technology. This technology mainly relies on the moiré magnification effect generated when a microlens array and a micro-image array are superimposed to project two-dimensional micro-images at different heights in three-dimensional space. This allows the observer to directly observe a stereoscopic visual effect with dynamic changes or a sense of suspension without any auxiliary equipment.

[0003] The core of this technology lies in the precise periodic matching relationship between the microlens array and the microimage array. In existing technologies, the imaging height of the stereoscopic image is typically controlled by constructing a mathematical model and adjusting the period of the microimage array relative to the microlens array. However, this traditional method has significant limitations. Traditional methods only control height by adjusting the period, without compensating for the resulting magnification variations. This leads to inconsistent image element sizes at different spatial heights, resulting in imaging distortion and severely affecting the realism and uniformity of the stereoscopic display.

[0004] Secondly, the above methods are limited by the actual level of micro-nano fabrication technology. The ability to adjust the size and position of micro-image units is limited by the resolution of the processing equipment. When the target imaging height is too far from the zero-height plane, the difference between the calculated micro-image period and the reference period is too small to be accurately processed, resulting in layering in the imaging. This not only limits the effective imaging height range but also restricts the expressive power of stereoscopic imaging.

[0005] Therefore, there is an urgent need in this field for an innovative micro-image array design method that can effectively solve the problem of inconsistent magnification caused by changes in height while achieving spatial stereo imaging, and take into account the process limitations of actual micro-nano fabrication, so as to improve the imaging quality performance of existing technologies.

[0006] A search revealed a Chinese patent document disclosing a method for fabricating discrete magnified images using microlens arrays and an optical imaging thin film [Application No.: 202311039282.1, Publication No.: CN119493268A]. This method includes: determining the initial center point position and initial period of each image in the image layer; modeling the stereoscopic image to be presented by the optical imaging thin film to obtain a stereoscopic model. While the patent can model a stereoscopic image and determine the period based on the model height, and then obtain the magnification based on the target period and the microlens period, exhibiting the characteristics of adjusting the center position and generating the target graphic layer, this invention introduces micro / nano fabrication resolution and observation resolution to determine the effective minimum period difference and effective height range before generating the discrete period matrix. Furthermore, this invention uses a discrete scaling factor to compensate for the magnification differences caused by different heights, and combines period offset and size scaling for micro-image array generation. Therefore, this invention provides a more complete linkage design for manufacturability constraints and distortion suppression. Summary of the Invention

[0007] To address the problems existing in the prior art, the present invention aims to provide a method for generating a micro-image array for spatial stereoscopic imaging and an optical imaging thin film.

[0008] A method for generating a micro-image array for spatial stereo imaging, characterized in that it includes: S1: Obtain Rp, Rh, TL, f, and n, calculate ΔT'min and quantize it according to Rp to obtain ΔTmin, and calculate the effective height range H; S2: Given the expected imaging size S and stereoscopic effect, map the grayscale of the two-dimensional image to the height to obtain matrix G; S3: With the reference point as the center, map G into a discrete periodic matrix GT; S4: Calculate the discrete scaling factor Z based on GT; S5: Determine the period offset of each discrete unit according to GT and adjust the position of the reference micro-graphics. At the same time, scale the size according to Z to obtain the target graphics of each discrete unit. Then, array the target graphics to generate the target micro-image array. S6: Generate a microlens array that matches the target micro-image array and align the stacked layers to achieve spatial stereo imaging.

[0009] Preferably, Rp is the horizontal resolution of the micro / nano fabrication; Rh is the observation resolution; TL is the microlens array period; f is the microlens focal length; n is the material refractive index; ΔT'min is the theoretical minimum period difference; ΔTmin is the effective minimum period difference obtained after quantizing and rounding up ΔT'min; H is the effective imaging height range; S is the expected imaging size; G is the gray-level space matrix, and its pixel gray-level values ​​are used to characterize the imaging height at the corresponding position; GT is the discrete period matrix; Z is the discrete scaling factor; h is the imaging height information at the position corresponding to the gray-level space matrix G; ΔT is the discrete period difference; and TP is the unit period of the discrete unit corresponding to the micro-image array.

[0010] The above technical solution enables the generation of a micro-image array that matches the target stereoscopic effect while meeting the resolution constraints of micro-nano fabrication. Furthermore, it compensates for magnification differences caused by varying imaging heights using discrete scaling factors, resulting in a spatial stereoscopic imaging size closer to the expected size and reducing local dimensional inconsistencies and imaging distortions caused by height variations. Simultaneously, this invention determines the effective minimum period difference and effective imaging height range before generating the discrete period matrix, ensuring clear and achievable boundaries for subsequent period difference discretization and array generation, thus balancing stereoscopic effect with manufacturability.

[0011] Specifically, in step S1, the theoretical minimum period difference ΔT'min is obtained through a nonlinear imaging height model, and then quantized and rounded up according to the micro / nano fabrication horizontal resolution Rp to obtain ΔTmin. This processing ensures that the period difference setting is no longer limited to a theoretical value, but is transformed into a discrete level that can be achieved in actual fabrication. After further converting the effective imaging height range H based on ΔTmin, step S2, which maps the two-dimensional image grayscale to the height matrix G, has clear upper and lower limits for the height. This limiting mechanism can avoid allocating the target height to a range that is difficult to achieve in fabrication, thereby reducing height dispersion distortion caused by excessively small period differences, and also making the three-dimensional height transition of different regions more controllable.

[0012] In steps S3 to S5, the present invention maps height information into a discrete periodic matrix GT centered on a reference point, thereby determining the period offset of each discrete unit. This period offset is used to adjust the position of the reference micro-image to form a phase / period relationship corresponding to the height. Simultaneously, the present invention further calculates a discrete scaling factor Z based on GT and synchronously scales the reference micro-image when generating the target micro-image array. In this way, the periodic offset is responsible for achieving height layering and stereoscopic visual effects, while the discrete scaling is responsible for compensating for differences in imaging magnification caused by different heights. Both work collaboratively within the same generation process, making the final size after imaging by the microlens array closer to the expected imaging size S, resulting in better proportional consistency of the overall stereoscopic image.

[0013] In practical applications, the target micro-image array and microlens array generated by this invention are aligned and stacked in step S6 to form a spatial stereoscopic imaging film or related optical devices. Because this invention unifies the processing resolution, observation resolution, and imaging height range into a single parameter system at the front end, and introduces joint control of periodic offset and discrete scaling during array generation, this method is more suitable for decorative and anti-counterfeiting applications requiring stable stereoscopic effects. It also facilitates rapid parameter adjustment under different process conditions while maintaining consistent imaging results.

[0014] Preferably, the theoretical minimum period difference ΔT'min mentioned in step S1 is calculated by a nonlinear imaging height model and satisfies: ; The step S1, which quantizes ΔTmin according to Rp, includes the following: Round up to ensure that ΔTmin is a minimum integer multiple of Rp that is not less than ΔT'min, and that ΔTmin satisfies: ; in, This represents the smallest integer not less than x that is obtained by rounding x up.

[0015] The above technical solution transforms the theoretical minimum period difference ΔT'min into an effective minimum period difference ΔTmin that satisfies the processing resolution constraint. This transformation converts continuous theoretical values ​​into discrete, realizable values. It also provides a unified step scale for subsequent discretization calculations. Therefore, this transformation facilitates placing optical model parameters and processing parameters within the same computational framework.

[0016] Specifically, this invention first obtains ΔT'min based on a nonlinear imaging height model. This ΔT'min reflects the lower limit of the resolvable period difference of the system under a given observation resolution and optical parameters. This invention then uses the micro / nano fabrication horizontal resolution Rp as the quantization unit. This invention quantizes ΔT'min and uses an up-rounding rule to obtain ΔTmin. This ΔTmin is not less than ΔT'min. This ΔTmin also satisfies the requirement of "machinable discrete level." This process avoids the period difference falling within the range where fabrication cannot be stably achieved.

[0017] In practical design, ΔTmin provides the basis for determining the subsequent effective height range H. ΔTmin also provides a lower bound constraint on the discretization of the period difference of each discrete element in the discrete periodic matrix GT. This constraint reduces the possibility of overly dense hierarchical levels in the subsequently calculated period differences. This constraint also makes the discrete levels of height hierarchy more controllable. Therefore, this constraint helps improve the consistency of the method output.

[0018] Preferably, the effective height range H in step S1 is obtained by converting ΔTmin, and satisfies: .

[0019] Through the above technical solution, this invention can determine the effective imaging height range H based on ΔTmin. This height range provides upper and lower bounds for the allocation of stereoscopic height targets. It also provides a constraint boundary for the mapping from grayscale to height. This height range ensures that subsequent period difference calculations are performed only within the achievable interval. Therefore, this height range helps avoid abnormal design values ​​caused by height targets exceeding their limits.

[0020] Specifically, this invention calculates the upper and lower limits of H based on the focal length f, the microlens array period TL, the material refractive index n, and ΔTmin. These upper and lower limits define the effective imaging height range that can be formed under the current ΔTmin condition. This range coincides with the minimum period difference achievable in fabrication. This range also matches the microlens imaging geometry. This invention can reference this range when constructing the grayscale space matrix G or generating the discrete period matrix GT. This reference creates a closed-loop constraint between the height output and the period difference output.

[0021] In practical applications, H can be used as the height output range for stereo modeling of two-dimensional images. H can also be used to limit the height matrix results. This limiting process can reduce excessive height jumps near boundaries. It can also reduce the risk of densely distributed period differences within extremely small intervals. Therefore, this limiting process helps maintain the controllability and continuity of the stereo height hierarchy.

[0022] Preferably, the stereoscopic effect in step S2 includes one or more of the following: planar suspension, sinking, tilting, or a three-dimensional curved surface with undulating texture; the grayscale mapping in step S2 includes converting the grayscale values ​​of two-dimensional image pixels into imaging height information to construct a grayscale space matrix G.

[0023] Through the above technical solution, this invention can map height information h into a period difference ΔT, forming a discrete period matrix GT. This matrix transforms the height target of each discrete unit into a period difference target. This matrix establishes a correspondence between height and the microlens array period TL. Therefore, this matrix can serve as the basis for calculating the period offset. This matrix also provides the input basis for calculating the discrete scaling factor Z.

[0024] Specifically, this invention obtains the imaging height h corresponding to a pixel from the gray-level space matrix G. This h comes from the mapping result of gray-level to height in a two-dimensional image. This h varies within the effective height range H. Based on h, this invention calculates the period difference ΔT between the cell period TP of the discrete unit of the micro-image array and the period TL of the microlens array. This ΔT reflects the distribution of period differences corresponding to different heights. This invention then quantizes ΔT by Rp and rounds it up. This processing brings ΔT to a workable discrete level. This processing also gives GT a discrete, realizable matrix representation.

[0025] In actual generation, ground truth (GT) is used to determine the periodic offset relationship of each discrete unit. GT is used to calculate the offset of each discrete unit relative to its initial position. This offset is used to adjust the position of the reference micro-pattern. This position adjustment corresponds to the height target. This position adjustment also corresponds to the microlens imaging relationship. This matrixing process thus makes the stereoscopic effect spatially programmable and facilitates control by pattern area.

[0026] Preferably, the mapping of G to a discrete periodic matrix GT in step S3 includes: obtaining the imaging height h corresponding to the pixel from the gray-scale space matrix G; determining the discrete period difference ΔT between the unit period TP of the discrete unit corresponding to the micro-image array and the period TL of the microlens array based on the imaging height h, and quantizing and rounding up ΔT to form the discrete periodic matrix GT; wherein ΔT satisfies: .

[0027] Through the above technical solution, this invention can calculate the discrete scaling factor Z based on the discrete periodic matrix GT. This Z is used to compensate for differences in imaging magnification caused by different imaging heights. This Z makes different discrete units closer to the same expected imaging size S after imaging. This compensation mechanism can work in conjunction with a periodic offset mechanism. Therefore, this compensation mechanism helps to reduce local dimensional inconsistencies and distortion trends.

[0028] Specifically, this invention determines the magnification variation of each discrete unit based on ground truth (GT) and the microlens imaging principle. This variation arises from the different heights of the discrete units and from the different period difference distributions. This invention configures the discrete scaling factor Z as a magnification compensation amount. When generating the target micro-image array, this invention performs a periodic offset on the reference micro-image according to GT. Simultaneously, this invention scales the reference micro-image according to Z. This scaling is performed separately for each discrete unit. This scaling and offset together determine the target image. This process incorporates imaging size consistency control during the generation stage.

[0029] In layered imaging, GT primarily corresponds to the formation of height layers, while Z primarily corresponds to the compensation for differences in image size. Both work together to influence the imaging result after the microlens array. This combined effect allows the image to maintain a closer proportional relationship across different depth layers. It also results in smoother dimensional transitions in edge regions. This combined effect thus contributes to improving the overall consistency of the stereoscopic image.

[0030] Preferably, the calculation of the discrete scaling factor Z in step S4 includes: determining the imaging magnification caused by the different imaging heights of each discrete unit in the micro-image array based on the discrete periodic matrix GT and the microlens imaging principle; the discrete scaling factor Z is configured to compensate for the inconsistent imaging magnification between the discrete units, so that the imaging size after passing through the microlens array is consistent with the expected imaging size S; and Z satisfies: .

[0031] Through the above technical solution, the present invention can form an optical imaging thin film comprising a micro-image array layer, a dielectric layer, and a microlens array layer. This thin film employs an aligned stacked structure. This thin film can output spatial stereoscopic imaging effects. This thin film translates the calculation results of the method into a device structure. Therefore, this thin film is convenient for application and integration as a finished product.

[0032] Specifically, the micro-image array layer is generated by the method of the present invention. The micro-image array layer contains target micro-patterns that are periodically offset according to GT and scaled according to Z. The microlens array layer is arranged periodically in TL. The microlens array layer and the micro-image array layer are aligned by array units. A dielectric layer is disposed between the micro-image array layer and the microlens array layer. The dielectric layer is used to realize the stacked structure and provide interlayer spacing. This structure ensures that each microlens unit matches its corresponding micro-image unit.

[0033] In use, the microlens array images the micro-image array. An observer can obtain a stereoscopic visual effect under certain observation conditions. This stereoscopic effect is consistent with the stereoscopic effect set in step S2. The imaging size corresponds to the expected imaging size S. Therefore, this thin-film structure conveys the design intent of "periodic offset + scaling compensation" to the actual imaging.

[0034] An optical imaging thin film, characterized in that it comprises a micro-image array layer, a dielectric layer, and a microlens array layer; the microlens array layer is arranged in a periodic TL pattern and stacked with the micro-image array layer to obtain a spatial stereoscopic imaging effect; the optical imaging thin film is used for surface decoration or anti-counterfeiting elements.

[0035] Through the above technical solution, the present invention enables the optical imaging film to be applied to surface decorations or anti-counterfeiting components. This carrier can present a spatial stereoscopic imaging effect. This carrier can combine pattern information with height information. This carrier can also retain microstructure array features in the finished product. Therefore, this carrier has a clear device form and application form.

[0036] Specifically, the surface decoration or anti-counterfeiting element includes the optical imaging film. The film achieves stereoscopic imaging through the aligned stacking of a micro-image array and a microlens array. The micro-image array is obtained by mapping from a grayscale space matrix G. The micro-image array is further constrained by a discrete periodic matrix GT and a discrete scaling factor Z. GT provides the periodic offset rule. Z provides the size compensation rule. This structural feature is realized by a microstructure array. This structural feature corresponds one-to-one with the method steps.

[0037] In application, the carrier can present visual effects such as suspension, sinking, tilting, or undulating textured surfaces. The carrier can also present different height levels in different pattern areas. Furthermore, the carrier can use the expected imaging size S as a consistency target. This application method is therefore consistent with the generation logic of this invention and facilitates parametric design for different patterns.

[0038] Compared with the prior art, the present invention has the following advantages: 1. This invention incorporates processing resolution and observation conditions as constraints during the design phase. The method first determines the achievable minimum period difference and effective imaging height range based on these constraints, then completes the grayscale-to-height mapping within this range, and converts continuous height variations into a processable discrete periodic distribution. This process ensures that the setting of the 3D height remains within the process boundaries, and also makes it easier to maintain controllable and consistent 3D layers and transitions in different regions.

[0039] 2. This invention, while generating 3D height through periodic offset, introduces a discrete scaling factor to compensate for differences in imaging magnification. This method links position adjustment with size scaling when generating micro-images, allowing the scaling to change with the discrete periodic distribution. Therefore, the image proportions of different height layers are more likely to remain similar, the distortion caused by local size inconsistencies is less pronounced, and the overall proportions and edge transitions of the 3D image are more natural. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the process of this invention; Figure 2 This is a schematic diagram of the superposition of the micro-image array and the microlens array of the present invention; Figure 3 This is a schematic diagram of the structure of the optical imaging thin film of the present invention; Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] The present invention will be described in detail below through multiple embodiments and comparative examples. These embodiments are intended to further illustrate the technical solutions and beneficial effects of the present invention, and are not intended to limit the scope of protection of the present invention. Unless otherwise specified, all parts mentioned in the present invention are parts by weight, and the process equipment mentioned is conventional equipment in the art.

[0043] like Figure 2 As shown, a microlens array 3 is generated that periodically matches the target micro-image array 1, and the two are aligned and stacked to form a high-quality spatial stereoscopic imaging effect.

[0044] like Figure 3 As shown in the figure, this is a schematic diagram of the structure of an optical imaging thin film, which consists of an image array 1, a medium 2, and a microlens array 3.

[0045] This invention provides a method for generating micro-image arrays for spatial stereo imaging. This method corresponds to… Figure 1 The method comprises steps S1 to S6. It uses processing resolution and observation resolution as design constraints. It uses the microlens array period and focal length as its optical basis. The method converts the grayscale information of a two-dimensional image into spatial height information. It then converts the spatial height information into a discrete periodic difference distribution. The method also introduces a discrete scaling factor, which is used to compensate for magnification differences caused by height variations. Finally, the method generates a target micro-image array. This target micro-image array and the microlens array are aligned and stacked to form a spatial stereoscopic imaging structure.

[0046] 1. Step S1 Step S1 is used to calculate the effective height range H in conjunction with processing constraints. The system first determines the input parameters. The system determines the horizontal resolution Rp of the micro / nano fabricated two-dimensional plane. The system determines the observation resolution Rh. The system determines the microlens array period TL. The system determines the microlens focal length f. The system determines the material refractive index n. The system uses a nonlinear imaging height model to calculate the theoretical minimum period difference ΔT'min. The theoretical minimum period difference ΔT'min satisfies the following equation: ; Where Rp is the horizontal resolution of the micro / nano fabrication. Rh is the observation resolution. TL is the microlens array period. f is the microlens focal length. n is the material refractive index. ΔT'min is the theoretical minimum period difference. This ΔT'min represents the minimum period difference level that the system can resolve under current optical and observation conditions. This ΔT'min may still be a continuous value. This ΔT'min may not necessarily meet the process discrete step rate.

[0047] The system then converts ΔT'min into the actual processable effective minimum period difference ΔTmin. The system uses Rp as the quantization unit. The system quantizes ΔT'min and rounds it up. ΔTmin satisfies the following equation: ; in, This indicates rounding x up. This operation yields the smallest integer not less than x. This process makes ΔTmin an integer multiple of Rp. This process also makes ΔTmin not less than ΔT'min. This process thus brings the theoretical constraints down to the manufacturable discrete periodic difference.

[0048] The system then calculates the effective imaging height range H from ΔTmin. H satisfies the following formula: ; Here, H represents the effective imaging height range. This range defines the upper and lower bounds for the height design. When the system subsequently maps the grayscale of the 2D image to height, it restricts the height to this range. This prevents the system from assigning height targets to unattainable intervals. It also reduces the discrete layering problem caused by excessively small period differences.

[0049] 2. Step S2 and grayscale matrix G Step S2 is used for image height grayscale mapping. The system loads a 2D image. The system sets the expected imaging size S. The system uses the expected imaging size S as the reference image size for the micro-image array. The system sets the spatial stereoscopic effect to be presented. This stereoscopic effect can be planar or tilted. It can also be floating or sunken. It can also be a undulating textured surface. The system performs height mapping of the stereoscopic effect in grayscale quantization. The system constructs a grayscale space matrix G. The pixel grayscale values ​​in matrix G are used to represent the imaging height at the corresponding position. The system can use zero height as a reference. The system can use 8-bit quantization. Under this quantization, the system sets the highest pixel value to 255. Under this quantization, the system sets the lowest pixel value to 0. After matrix G is established, the system can preview the stereoscopic height distribution of the target. The system will also limit the height output within the effective imaging height range H.

[0050] 3. Step S3 Step S3 is used to generate the discrete periodic matrix GT. The system selects a reference point in the two-dimensional image. This reference point serves as the image center. The system obtains the height information h from the gray-level space matrix G. The system combines the effective imaging height range H with the micro / nano fabrication horizontal resolution Rp to quantize and round up the height information h. The system maps the quantized height information to a discrete periodic difference ΔT. The system uses the ΔT of each discrete unit to construct the discrete periodic matrix GT. The discrete periodic difference ΔT satisfies the following equation: ; Where TP is the cell period of the discrete unit corresponding to the micro-image array, TL is the microlens array period, ΔT is the discrete period difference, and h is the imaging height information of the position corresponding to the gray-scale space matrix G. The system converts the height h into the period difference ΔT according to the formula. The system then quantizes and rounds up ΔT. The system thus obtains a processable discrete period difference level. The system then obtains the discrete period matrix GT. This GT spatially describes the period difference distribution corresponding to different regions. This GT also provides a basis for subsequent period offset calculations.

[0051] 4. Step S4 Step S4 is used to generate a micro-image scaling factor based on the periodic matrix. The system calculates the periodic offset of each discrete unit relative to its initial position based on the discrete periodic matrix GT. The system then calculates the discrete scaling factor Z based on the microlens imaging principle. The system configures Z as a compensation amount to eliminate imaging distortion. The system uses Z to compensate for the magnification difference caused by different imaging heights. The system ensures that the imaging size of all discrete units after passing through the microlens array is consistent with the expected imaging size S. The discrete scaling factor Z satisfies the following equation: ; Where Z is the discrete scaling factor, ΔT is the discrete period difference, and TL is the microlens array period. The system uses both the period offset and the discrete scaling factor Z simultaneously when generating the micro-pattern. The system adjusts the position of the reference micro-pattern and scales its size. The system then obtains the target pattern for each discrete unit. This coordinated processing ensures that height hierarchy and imaging size consistency are controlled within the same workflow.

[0052] 5. Step S5 and generation of the target micro-image array Step S5 is used to generate a micro-image array. The system performs an arraying operation on the discrete unit target graphics obtained in step S4. The system arranges the target graphics according to array rules. The system forms an optimized target micro-image array. This target micro-image array has different periodic offset states locally. This target micro-image array has different scaling states locally. This difference corresponds to the height distribution in the gray-level space matrix G. This difference also corresponds to the period difference distribution in the discrete periodic matrix GT.

[0053] 6. Step S6 and the structure of optical imaging thin film products Step S6 is used to generate a microlens array and achieve spatial stereo imaging. The system generates a microlens array whose period matches that of the target micro-image array. The system aligns and stacks the target micro-image array and the microlens array. The system forms a spatial stereo imaging structure. Figure 2 The superposition relationship between the micro-image array and the microlens array is shown. Figure 3 The layered structure of the optical imaging thin film is shown.

[0054] like Figure 3 As shown, this invention also provides an optical imaging thin film product. The thin film structure includes a micro-image array 1, a medium 2, and a microlens array 3. The micro-image array 1 is the target micro-image array generated by the method of this invention. The microlens array 3 arranges lens units in a periodic TL arrangement. The medium 2 is disposed between the micro-image array 1 and the microlens array 3. The system achieves spatial stereoscopic imaging after alignment and stacking. This thin film can be used in applications such as surface decoration, stereoscopic display, and anti-counterfeiting packaging.

[0055] Example 1: Generation and Parameter Calculation of Stereoscopic Imaging Thin Film with Triangular Pattern Reference Figure 1 This embodiment provides a micro-image array optimization method for spatial stereo imaging. The method includes steps S1 to S6. The method uses micro / nano fabrication resolution and observation resolution as constraint inputs. The method uses the microlens array period TL, the microlens focal length f, and the material refractive index n as optical inputs. The method ultimately generates a target micro-image array 1, which is then aligned and stacked with a microlens array 3 to form a spatial stereo imaging structure.

[0056] Step S1: Calculate the effective height range based on processing constraints.

[0057] In this embodiment, the resolution of the human eye at a viewing distance of 250mm is used as the observation resolution Rh, which is approximately 0.1mm. The pre-designed microlens array period TL is 100µm. The pre-designed microlens focal length f is 100µm. The pre-designed material refractive index n is 1.55. This embodiment utilizes grayscale direct writing technology for micro-nano fabrication. The two-dimensional planar horizontal resolution Rp of this process is 0.5µm. The system calculates the theoretical minimum period difference ΔT'min based on a nonlinear imaging height model, and ΔT'min satisfies formula (1): ; The system calculates the theoretical minimum processing cycle difference to be approximately 5.529 μm under the current parameter conditions. The system then quantizes and rounds up ΔT'min based on the micro / nano fabrication horizontal resolution Rp to determine the actual processable effective minimum cycle difference ΔTmin, which satisfies formula (2): ; in, This represents the smallest integer not less than x, obtained by rounding up. The system calculates the effective minimum period difference ΔTmin to be 6.0 μm. The system converts ΔTmin into the effective imaging height range H, which satisfies formula (3): ; The system calculates that the effective imaging height range is approximately -1.075 mm to 1.075 mm. Based on this, the system determines that the overall achievable height range is approximately 2.15 mm. The system then limits the height output to this range during subsequent height mapping and discretization processes.

[0058] Step S2, image high-grayscale mapping.

[0059] The system loads a 2D image of a triangle. The system sets the expected imaging size S, with both length and width of S being 50mm × 50mm. The system uses the expected imaging size S as the reference image size for the micro-image array 1. The system performs height modeling based on a preset stereoscopic effect. This stereoscopic effect can be planar or tilted. It can also be floating or sunken. It can also be a undulating textured surface. The system maps the stereoscopic effect to height using grayscale quantization, constructing a grayscale space matrix G. The pixel grayscale value in matrix G represents the imaging height of that point. In this embodiment, zero height is used as the reference. The system uses 8-bit grayscale quantization. The system sets the pixel value of the highest imaging point to 255. The system sets the pixel value of the lowest imaging point to 0. After generating the grayscale space matrix, the system can preview the stereoscopic height distribution of the target and constrain the height distribution within the effective imaging height range H obtained in step S1.

[0060] Step S3: Generate a discrete periodic matrix.

[0061] The system selects a reference point as the image center in the two-dimensional image. Combining the imaging height range H and the micro / nano fabrication horizontal resolution Rp, the system maps the height information h of the gray-scale space matrix G to a discrete period difference ΔT related to the microlens array period TL through quantization and rounding up, thus constructing a discrete period matrix GT. The period difference ΔT satisfies formula (4): ; Where TP is the cell period of the discrete unit corresponding to the micro-image array. The system converts the height h into the period difference ΔT using formula (4). The system then quantizes and rounds up ΔT to bring it down to a processable discrete level. For example, the system assumes that the expected imaging height h of a certain discrete unit is 0.5 mm. The system calculates that the cell period difference ΔT is 12.903 μm. The system optimizes the discrete cell period difference to 13.0 μm through quantization and rounding up. The system obtains the discrete period matrix GT of the entire image in the same way.

[0062] Step S4: Generate the micro-image scaling factor based on the periodic matrix.

[0063] The system calculates the periodic offset of each discrete unit in the micro-image array 1 relative to its initial position based on the discrete periodic matrix GT. The system then calculates the discrete scaling factor Z, used to eliminate imaging distortion, based on the microlens imaging principle and the periodic offset, to ensure that the imaging size of all discrete units after passing through the microlens array 3 is consistent with the expected imaging size S. The discrete scaling factor Z satisfies formula (5): ; The system processes the reference micro-image based on the period offset and the discrete scaling factor Z. The system adjusts the position of the reference micro-image accordingly. The system scales the reference micro-image accordingly. The system then generates the target image for each discrete unit. For example, the system assumes that the period difference ΔT of a certain discrete unit is 13.0 μm. The system obtains the scaling factor Z of the discrete unit as 0.13 using formula (5). The system performs scaling calculations based on the expected imaging size S as the reference image size, and the micro-image size of the discrete unit is 6.5 mm × 6.5 mm. The system repeats the above calculation process for other discrete units according to their corresponding ΔT and Z.

[0064] Step S5: Generate a micro-image array.

[0065] The system performs array-based operations on all discrete units. The system arranges the target graphics of each discrete unit according to array rules. The system ultimately forms an optimized target micro-image array 1.

[0066] Step S6: Generate a microlens array and achieve spatial stereo imaging.

[0067] Reference Figure 2 The system generates a microlens array 3 that periodically matches the target micro-image array 1. The microlens array 3 arranges lens elements at a periodic TL. The system aligns and stacks the target micro-image array 1 and the microlens array 3. The system thus forms a spatial stereoscopic imaging structure and achieves a stereoscopic display effect.

[0068] Reference Figure 3This embodiment also provides an optical imaging thin film structure. The structure includes an image array 1, a medium 2, and a microlens array 3. The system aligns and stacks the image array 1, the medium 2, and the microlens array 3 to obtain a spatial stereoscopic imaging effect.

[0069] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for generating a spatially stereoscopic microimage array, the method comprising: include: S1: Obtain Rp, Rh, TL, f, and n, calculate ΔT'min and quantize it according to Rp to obtain ΔTmin, and calculate the effective height range H; S2: Given the expected imaging size S and stereoscopic effect, map the grayscale of the two-dimensional image to the height to obtain matrix G; S3: With the reference point as the center, map G into a discrete periodic matrix GT; S4: Calculate the discrete scaling factor Z based on GT; S5: Determine the period offset of each discrete unit according to GT and adjust the position of the reference micro-graphics. At the same time, scale the size according to Z to obtain the target graphics of each discrete unit. Then, array the target graphics to generate the target micro-image array. S6: Generate a microlens array that matches the target micro-image array and align the stacked layers to achieve spatial stereo imaging.

2. The method of claim 1, wherein: Rp represents the horizontal resolution of the micro / nano fabrication; Rh represents the observation resolution; TL represents the microlens array period; f represents the microlens focal length; n represents the material refractive index; and ΔT'min represents the theoretical minimum period difference. ΔTmin is the effective minimum period difference obtained after quantizing and rounding up ΔT'min; H is the effective imaging height range; S is the expected imaging size; G is the gray-level space matrix, and its pixel gray-level values ​​are used to characterize the imaging height at the corresponding position; GT is the discrete period matrix; Z is the discrete scaling factor; h is the imaging height information at the corresponding position of the gray-level space matrix G; ΔT is the discrete period difference; TP is the cell period of the discrete unit corresponding to the micro-image array.

3. The method of claim 1, wherein, The theoretical minimum period difference ΔT'min mentioned in step S1 is calculated by the nonlinear imaging height model and satisfies: ； The step S1, which quantizes ΔTmin according to Rp, includes the following: Round up to ensure that ΔTmin is a minimum integer multiple of Rp that is not less than ΔT'min, and that ΔTmin satisfies: ； in, This represents the smallest integer not less than x that is obtained by rounding x up.

4. The method according to claim 1, characterized in that, The effective height range H mentioned in step S1 is obtained by converting ΔTmin, and satisfies: 。 5. The method according to claim 1, characterized in that, The stereoscopic effect described in step S2 includes one or more of the following: planar suspension, sinking, tilting, or a three-dimensional curved surface with undulating texture; the grayscale mapping described in step S2 includes converting the grayscale values ​​of two-dimensional image pixels into imaging height information to construct a grayscale space matrix G.

6. The method according to claim 1, characterized in that, Step S3, mapping G to a discrete periodic matrix GT, includes: obtaining the imaging height h corresponding to the pixel from the gray-level space matrix G; determining the discrete period difference ΔT between the cell period TP of the discrete unit corresponding to the micro-image array and the period TL of the microlens array based on the imaging height h; and quantizing and rounding up ΔT to form the discrete periodic matrix GT; wherein ΔT satisfies: 。 7. The method according to claim 1, characterized in that, Step S4, calculating the discrete scaling factor Z, includes: determining the imaging magnification of each discrete unit in the micro-image array due to different imaging heights, based on the discrete periodic matrix GT and the microlens imaging principle; the discrete scaling factor Z is configured to compensate for the inconsistent imaging magnification between the discrete units, so that the imaging size after passing through the microlens array is consistent with the expected imaging size S; and Z satisfies: 。 8. An optical imaging thin film, characterized in that, It includes a micro-image array layer, a dielectric layer, and a microlens array layer; the micro-image array layer is a target micro-image array generated by the method described in any one of claims 1 to 7; the microlens array layer is arranged in a periodic TL pattern and stacked with the micro-image array layer to obtain a spatial stereoscopic imaging effect.

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