A liquid crystal lens aberration compensation method based on a segmented high-resistance layer electrode

Abstract

The present application relates to the technical field of liquid crystal lens, and relates to a liquid crystal lens aberration compensation method based on a segmented high-resistance layer electrode, comprising the following steps: S1, a simulation model of a mode control liquid crystal lens is established, and the high-resistance layer electrode is divided into at least two independent electrical sections which are electrically insulated from each other in space; S2, based on the simulation model, a driving voltage is applied to the mode control liquid crystal lens to obtain a refractive index distribution curve; S3, the refractive index distribution curve is compared with an ideal parabolic refractive index distribution curve to identify a distortion side; S4, the square resistance value of the high-resistance layer electrical section corresponding to the distortion side is set as a to-be-adjusted value, and the square resistance value of the high-resistance layer electrical section corresponding to the non-distortion side is maintained as a reference value; S5, the to-be-adjusted value is optimized to determine a target square resistance value; and S6, the high-resistance layer electrode is prepared according to the target square resistance value and the reference value respectively. The present application effectively suppresses the asymmetric distortion of the refractive index distribution and significantly improves the imaging quality.

Description

Technical Field

[0001] This invention relates to the technical field of liquid crystal lenses, and more specifically, to a method for aberration compensation of liquid crystal lenses based on segmented high-resistivity layer electrodes. Background Technology

[0002] Liquid crystal lenses, as electrically controllable focusing optical devices, require no moving mechanical parts and have a fast response speed, making them promising for applications in compact optical systems such as miniaturized camera modules, biomedical imaging, and machine vision. Modal control liquid crystal lenses, due to their simple structure and continuously adjustable optical power, have become a research hotspot. Their principle utilizes the non-uniform electric field between the circular electrode and the surface electrode to cause the refractive index of the liquid crystal molecules to change continuously in space, forming an equivalent lens effect. To achieve controllable orientation of the liquid crystal molecules, a polyimide alignment layer is required, which, after rubbing, imparts a pretilt angle to the liquid crystal molecules to prevent the formation of reverse domains.

[0003] However, the pretilt angle also introduces optical defects. Because the friction directions of the alignment layers on both sides of the lens are opposite, the initial tilt directions of the liquid crystal molecules are also opposite. Under the drive of the electric field, their deflection does not start from a symmetrical state, resulting in an asymmetric distortion of the refractive index distribution on the cross section parallel to the friction direction relative to the ideal parabola, causing a local bulge on one side of the lens. This distortion manifests as asymmetric aberration, mainly astigmatism, on the wavefront, causing the focal point to deviate from the ideal position, which is particularly significant in small-aperture systems. The traditional structure widely used in existing technologies employs a uniform high-resistivity layer electrode with constant sheet resistance, which cannot effectively compensate for the asymmetric distortion of the refractive index distribution, limiting further improvements in image quality. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies in effectively compensating for asymmetric distortion of refractive index distribution, which limits the improvement of image quality. This invention provides a liquid crystal lens aberration compensation method based on segmented high-resistivity layer electrodes, which effectively suppresses asymmetric distortion of refractive index distribution and significantly improves image quality.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for aberration compensation of a liquid crystal lens based on segmented high-resistivity layer electrodes is provided, comprising the following steps: S1. Establish a simulation model of a modally controlled liquid crystal lens. The simulation model includes liquid crystal material parameters, lens geometric structure parameters, and high-resistivity layer electrode parameters. The high-resistivity layer electrode in the modally controlled liquid crystal lens is spatially divided into at least two independent electrical segments that are electrically insulated from each other. S2. Based on the simulation model, apply a driving voltage to the modally controlled liquid crystal lens and obtain the refractive index distribution curve; S3. Compare the refractive index distribution curve with the ideal parabolic refractive index distribution curve to identify the distortion side where the refractive index distribution curve undergoes a local abrupt change relative to the ideal parabolic distribution; S4. Set the sheet resistance value of the high-resistivity layer electrical section corresponding to the distorted side as the value to be adjusted, and maintain the sheet resistance value of the high-resistivity layer electrical section corresponding to the non-distorted side as the reference value. S5. Optimize the value to be adjusted to determine the target sheet resistance value that minimizes the deviation between the refractive index distribution curve and the ideal parabolic distribution. S6. Prepare high-resistivity layer electrodes having at least two independent electrical sections according to the target resistance value and the reference value respectively.

[0006] The present invention discloses a method for aberration compensation in liquid crystal lenses based on segmented high-resistivity layer electrodes. First, a simulation model of a modally controlled liquid crystal lens is established, dividing the high-resistivity layer electrode into at least two electrically isolated independent segments. Then, a driving voltage is applied to this model to obtain a refractive index distribution curve. Subsequently, by comparing this curve with an ideal parabolic distribution, the distortion side experiencing local abrupt changes is identified. The sheet resistance value of the segment corresponding to the distortion side is then set as the value to be adjusted, while the sheet resistance value of the undistorted segment is maintained as a reference value. Next, a target sheet resistance value that minimizes the deviation between the refractive index distribution and the ideal distribution is determined through optimization. Finally, high-resistivity layer electrodes for each independent segment are fabricated according to the target sheet resistance value and the reference value. This invention, without increasing fabrication complexity and with good compatibility with existing manufacturing processes, can accurately compensate for asymmetric refractive index distortion caused by opposite pretilt angle directions, making the actual refractive index distribution approximate the ideal parabolic profile. It significantly reduces asymmetric wavefront aberrations across the entire aperture range, thereby maintaining the root mean square error of the wavefront at a low level over a wide optical power range, effectively improving the imaging clarity and consistency of the liquid crystal lens.

[0007] Preferably, in step S1, the liquid crystal material parameters include pretilt angle, vertical dielectric constant, parallel dielectric constant, stretch elastic coefficient, torsional elastic coefficient, bending elastic coefficient, unusual light refractive index, ordinary light refractive index, and liquid crystal conductivity; the geometric structure parameters include lens radius, liquid crystal layer thickness, planar electrode thickness, circular hole electrode thickness, and glass substrate thickness; the high-resistivity layer electrode parameters include relative dielectric constant and sheet resistance. By comprehensively incorporating liquid crystal material parameters such as pretilt angle, vertical dielectric constant, parallel dielectric constant, stretch elastic coefficient, torsional elastic coefficient, bending elastic coefficient, unusual light refractive index, ordinary light refractive index, and liquid crystal conductivity, as well as geometric structure parameters such as lens radius, liquid crystal layer thickness, electrode thickness, and glass substrate thickness, and simultaneously introducing the relative dielectric constant and sheet resistance parameters of the high-resistivity layer electrode, the simulation model can accurately reflect the actual orientation behavior of liquid crystal molecules under the action of an electric field and the electric field distribution inside the lens. This provides a reliable data foundation for the accurate identification of refractive index distortion positions and sheet resistance optimization, ensuring a high degree of consistency between the simulation results and the actual physical device.

[0008] Preferably, the high-resistivity layer electrode is spatially divided into two electrically insulated segments, a first electrical segment and a second electrical segment, along the direction of liquid crystal molecule friction. The dividing line between the first and second electrical segments corresponds to the distortion inflection point of the refractive index distribution curve relative to the ideal parabolic distribution. Dividing the high-resistivity layer electrode into two electrically insulated segments along the direction of liquid crystal molecule friction, with the dividing line corresponding to the distortion inflection point of the refractive index distribution curve relative to the ideal parabolic distribution, ensures that each electrical segment precisely covers an independent distortion region, achieving precise spatial segmentation of asymmetric refractive index distortion. Simultaneously, the division method of the left and right segments naturally matches the unidirectional distortion characteristics caused by existing friction processes, achieving the most effective asymmetric compensation with the fewest number of segments, and simplifying the electrode structure and fabrication process to the greatest extent possible while ensuring the compensation effect.

[0009] Preferably, in step S2, the driving voltage is an AC voltage with an effective value of 1V~3V and a frequency of 1kHz~3kHz. By using an AC voltage with an effective value of 1V~3V and a frequency of 1kHz~3kHz as the driving voltage, the liquid crystal molecules can fully respond to the change in electric field within this voltage range to generate the required refractive index modulation. At the same time, excessively high voltage is avoided, which may cause excessive tilting of the liquid crystal molecules or electrochemical instability. This ensures the stability and repeatability of the refractive index distribution of the lens during zooming, and creates stable and uniform test conditions for the accurate identification of the refractive index distortion position.

[0010] Preferably, in step S3, the method for identifying the distortion side where the refractive index distribution curve undergoes a local abrupt change relative to the ideal parabolic distribution is as follows: The refractive index distribution curve and the ideal parabolic distribution curve are plotted in the same coordinate system. By superimposing and comparing the curves, the side that deviates from the ideal parabolic distribution and whose bulge exceeds a preset threshold is identified as the distortion side. By plotting the actual refractive index distribution curve and the ideal parabolic distribution curve in the same coordinate system, and using curve superposition and comparison to identify the side that deviates from the ideal parabola and whose bulge exceeds a preset threshold as the distortion side, this identification method does not require complex mathematical transformations or iterative calculations. It can quickly locate the area to be compensated through intuitive curve comparison. It is simple to operate, has clear judgment criteria, lowers the technical implementation threshold, and the introduction of the preset threshold effectively avoids misjudgments caused by fluctuations in simulation values, improving the accuracy and robustness of distortion side identification.

[0011] Preferably, in step S3, when the refractive index distribution exists in three or more distorted regions within the lens aperture, the high-resistivity layer electrode is spatially divided into three or more electrically insulated segments corresponding to the number of distorted regions, and each segment can independently adjust its sheet resistance. When the refractive index distribution exists in three or more distorted regions within the lens aperture, dividing the high-resistivity layer electrode spatially into three or more electrically insulated segments corresponding to the number of distorted regions, and independently adjusting the sheet resistance of each segment, allows the compensation method of the present invention to be flexiblely extended to more complex multi-region distortion scenarios, significantly broadening the applicability of the method.

[0012] Preferably, in step S5, the method for optimizing the value to be adjusted to determine the target sheet resistance value is as follows: A parametric scan is performed on the sheet resistance value of the electrical segment of the high-resistivity layer electrode corresponding to the distorted side within the range of a first preset sheet resistance value to a second preset sheet resistance value. The root mean square error (RMSE) of the wavefront under each set of sheet resistance values ​​is calculated, and the sheet resistance value corresponding to the minimum value of the RMSE is determined as the target sheet resistance value. By employing a parametric scan of the segment corresponding to the distorted side within the range of a first preset sheet resistance value to a second preset sheet resistance value, and using the RMSE as an evaluation index, this optimization method transforms qualitative compensation into quantitative optimization. It replaces empirical trial and error with a clear mathematical evaluation standard, ensuring the objectivity and global optimality of the target sheet resistance value, avoiding suboptimal solutions due to local searches, and significantly improving compensation accuracy and optimization efficiency.

[0013] Preferably, in step S5, the first preset sheet resistance is 35 MΩ / sq, the second preset sheet resistance is 45 MΩ / sq, and the reference value is 40 MΩ / sq. These specific values ​​are the preferred parameter combinations determined through numerous simulation experiments. Parametric scanning within this sheet resistance range can cover the optimal solution range of the distortion side resistance with high accuracy, while effectively controlling the scanning range to avoid unnecessary waste of computational resources.

[0014] Preferably, in step S5, the scanning step size for parametric scanning of the value to be adjusted is 0.5 MΩ / sq to 1 MΩ / sq. This step size range achieves a reasonable balance between optimization accuracy and computational efficiency: too large a step size may cause the target square resistance value to deviate from the true optimal solution, while too small a step size will significantly increase the simulation computation load without improving accuracy. Using this preferred step size can ensure the fine resolution of the target square resistance value to meet the strict requirements of high-quality imaging for wavefront accuracy, while also controlling the simulation time within a reasonable range, thus possessing good engineering practicality.

[0015] Preferably, in step S6, the specific process for fabricating a high-resistivity layer electrode with at least two independent electrical sections is as follows: Differential deposition is performed on each electrical section on a glass substrate using mask sputtering or step-by-step deposition. By adjusting at least one process parameter among sputtering power, doping concentration, oxygen partial pressure, or deposition thickness, each electrical section obtains its corresponding target sheet resistance or reference value. This fabrication method, which uses mask sputtering or step-by-step deposition to perform differential deposition on each electrical section on a glass substrate and adjusts at least one process parameter among sputtering power, doping concentration, oxygen partial pressure, or deposition thickness to obtain the corresponding target sheet resistance or reference value, eliminates the need for additional photolithography layers or complex post-processing steps. It utilizes existing, maturely applied processes to achieve precise control of the sheet resistance of each section, exhibiting excellent process compatibility and mass production feasibility, while avoiding uncertainties and uniformity issues introduced by later adjustments.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. Effectively suppresses asymmetric distortion of refractive index distribution and significantly improves imaging quality. By dividing the high-resistivity layer electrode into at least two independent electrical segments that are insulated from each other, and separately optimizing the sheet resistance value for the distortion side caused by the pretilt angle, the actual refractive index distribution curve and the ideal parabolic distribution curve are maximized to achieve maximum overlap, effectively suppressing the local protrusion of refractive index on one side caused by the opposite direction of the pretilt angle. 2. It requires minimal structural modifications and has good process compatibility. It does not increase the complexity of the fabrication process. By simply changing the pattern design of the high-resistivity layer electrode, the originally continuous and uniform high-resistivity layer electrode can be divided into independent segments and their sheet resistance values ​​can be set separately. Aberration compensation can be achieved without changing the liquid crystal material system, alignment process, or driving circuit architecture. It has good industrial compatibility, does not add any additional post-processing steps, has controllable costs, and is easy to mass-produce. Attached Figure Description

[0017] Figure 1 This is a flowchart of a liquid crystal lens aberration compensation method based on segmented high-resistivity layer electrodes; Figure 2 This is a schematic diagram of the structure of a traditional modally controlled liquid crystal lens; Figure 3 This is a diagram showing the refractive index distribution of a conventional modally controlled liquid crystal lens. Figure 4 This is a schematic diagram of the modally controlled liquid crystal lens in this invention; Figure 5 This is a diagram showing the refractive index distribution of the modally controlled liquid crystal lens in this invention. Figure 6 This is a phase difference distribution diagram of the modally controlled liquid crystal lens in this invention; Figure 7 A comparison chart of wavefront root mean square errors; Figure 8 This is a comparison chart of peak-valley optical path difference. Detailed Implementation

[0018] The present invention will be further described below with reference to specific embodiments.

[0019] Example 1 This embodiment is the first embodiment of a liquid crystal lens aberration compensation method based on segmented high-resistivity layer electrodes, such as... Figure 1 As shown, it includes the following steps: S1. Establish a simulation model of the modally controlled liquid crystal lens. The simulation model includes liquid crystal material parameters, lens geometric structure parameters, and high-resistivity layer electrode parameters. The high-resistivity layer electrode in the modally controlled liquid crystal lens is spatially divided into at least two independent electrical segments that are electrically insulated from each other. S2. Based on the simulation model, apply a driving voltage to the modally controlled liquid crystal lens and obtain the refractive index distribution curve; S3. Compare the refractive index distribution curve with the ideal parabolic refractive index distribution curve to identify the distortion side where the refractive index distribution curve undergoes a local abrupt change relative to the ideal parabolic distribution. S4. Set the sheet resistance value of the high-resistivity layer electrical section corresponding to the distorted side as the value to be adjusted, and maintain the sheet resistance value of the high-resistivity layer electrical section corresponding to the non-distorted side as the reference value. S5. Optimize the value to be adjusted to determine the target sheet resistance value that minimizes the deviation between the refractive index distribution curve and the ideal parabolic distribution. S6. Prepare high-resistivity layer electrodes with at least two independent electrical sections according to the target resistance value and the reference value.

[0020] The present invention discloses a method for aberration compensation in liquid crystal lenses based on segmented high-resistivity layer electrodes. First, a simulation model of a modally controlled liquid crystal lens is established, dividing the high-resistivity layer electrode into at least two electrically isolated independent segments. Then, a driving voltage is applied to this model to obtain a refractive index distribution curve. Subsequently, by comparing this curve with an ideal parabolic distribution, the distortion side experiencing local abrupt changes is identified. The sheet resistance value of the segment corresponding to the distortion side is then set as the value to be adjusted, while the sheet resistance value of the undistorted segment is maintained as a reference value. Next, a target sheet resistance value that minimizes the deviation between the refractive index distribution and the ideal distribution is determined through optimization. Finally, high-resistivity layer electrodes for each independent segment are fabricated according to the target sheet resistance value and the reference value. This invention, without increasing fabrication complexity and with good compatibility with existing manufacturing processes, can accurately compensate for asymmetric refractive index distortion caused by opposite pretilt angle directions, making the actual refractive index distribution approximate the ideal parabolic profile. It significantly reduces asymmetric wavefront aberrations across the entire aperture range, thereby maintaining the root mean square error of the wavefront at a low level over a wide optical power range, effectively improving the imaging clarity and consistency of the liquid crystal lens.

[0021] In step S1, the liquid crystal material parameters include pretilt angle, vertical dielectric constant, parallel dielectric constant, stretch elastic coefficient, torsional elastic coefficient, bending elastic coefficient, extraordinary refractive index, ordinary refractive index, and liquid crystal conductivity; the geometric structure parameters include lens radius, liquid crystal layer thickness, planar electrode thickness, circular hole electrode thickness, and glass substrate thickness; the high-resistivity layer electrode parameters include relative dielectric constant and sheet resistance. By comprehensively incorporating liquid crystal material parameters such as pretilt angle, vertical dielectric constant, parallel dielectric constant, stretch elastic coefficient, torsional elastic coefficient, bending elastic coefficient, extraordinary refractive index, ordinary refractive index, and liquid crystal conductivity, as well as geometric structure parameters such as lens radius, liquid crystal layer thickness, electrode thickness, and glass substrate thickness, and simultaneously introducing the relative dielectric constant and sheet resistance parameters of the high-resistivity layer electrode, the simulation model can accurately reflect the actual orientation behavior of liquid crystal molecules under the action of an electric field and the electric field distribution inside the lens. This provides a reliable data foundation for the accurate identification of refractive index distortion positions and sheet resistance optimization, ensuring a high degree of consistency between the simulation results and the actual physical device.

[0022] The high-resistivity electrode is spatially divided into two electrically insulated segments, a first electrical segment and a second electrical segment, along the direction of liquid crystal molecule friction. The boundary between the first and second electrical segments corresponds to the distortion inflection point of the refractive index distribution curve relative to the ideal parabolic distribution. By dividing the high-resistivity electrode into two electrically insulated segments along the direction of liquid crystal molecule friction, and ensuring that the boundary corresponds to the distortion inflection point of the refractive index distribution curve relative to the ideal parabolic distribution, each electrical segment precisely covers an independent distortion region, achieving precise spatial segmentation of asymmetric refractive index distortion. Simultaneously, the segmentation method naturally matches the unidirectional distortion characteristics caused by existing friction processes, achieving the most effective asymmetric compensation with the fewest segments, and simplifying the electrode structure and fabrication process to the greatest extent possible while ensuring the compensation effect.

[0023] In step S2, the driving voltage is an AC voltage with an effective value of 1V~3V and a frequency of 1kHz~3kHz. By using an AC voltage with an effective value of 1V~3V and a frequency of 1kHz~3kHz as the driving voltage, the liquid crystal molecules can fully respond to the change in electric field and generate the required refractive index modulation within this voltage range. At the same time, excessively high voltage is avoided, which may cause excessive tilting of the liquid crystal molecules or electrochemical instability. This ensures the stability and repeatability of the refractive index distribution of the lens during zooming, and creates stable and uniform test conditions for the accurate identification of the refractive index distortion position in the future.

[0024] Example 2 This embodiment is the second embodiment of the aberration compensation method for liquid crystal lenses based on segmented high-resistivity layer electrodes. This embodiment is similar to Embodiment 1, except that in step S3, the method for identifying the distortion side where the refractive index distribution curve undergoes a local abrupt change relative to the ideal parabolic distribution is as follows: The refractive index distribution curve and the ideal parabolic distribution curve are plotted in the same coordinate system. By superimposing and comparing the curves, the side that deviates from the ideal parabolic distribution and whose bulge exceeds a preset threshold is determined as the distortion side. By plotting the actual refractive index distribution curve and the ideal parabolic distribution curve in the same coordinate system, and using curve superposition and comparison to determine the side that deviates from the ideal parabola and whose bulge exceeds a preset threshold as the distortion side, this identification method does not require complex mathematical transformations or iterative calculations. It can quickly locate the area to be compensated simply through intuitive curve comparison. The operation is simple, the judgment criteria are clear, and the technical implementation threshold is lowered. Furthermore, the introduction of the preset threshold effectively avoids misjudgments caused by fluctuations in simulation values, improving the accuracy and robustness of distortion side identification.

[0025] In step S3, when there are three or more distorted regions within the lens aperture due to the refractive index distribution, the high-resistivity layer electrode is spatially divided into three or more electrically insulated segments corresponding to the number of distorted regions. Each segment's sheet resistance can be independently adjusted. Dividing the high-resistivity layer electrode into three or more electrically insulated segments corresponding to the number of distorted regions, with each segment's sheet resistance independently adjusted, allows the compensation method of this invention to be flexible beyond a simple two-segment structure, extending to more complex multi-region distortion scenarios and significantly broadening its applicability.

[0026] In step S5, the method for optimizing the value to be adjusted to determine the target sheet resistance is as follows: A parametric scan is performed on the sheet resistance of the electrical segment of the high-resistivity layer electrode corresponding to the distorted side within the range of a first preset sheet resistance value to a second preset sheet resistance value. The root mean square error (RMSE) of the wavefront under each set of sheet resistance values ​​is calculated, and the sheet resistance value corresponding to the minimum RMSE is determined as the target sheet resistance value. By using a parametric scan of the corresponding segment on the distorted side within the range of the first preset sheet resistance value to the second preset sheet resistance value, and using the RMSE as an evaluation index, this optimization method transforms qualitative compensation into quantitative optimization. It replaces empirical trial and error with a clear mathematical evaluation standard, ensuring the objectivity and global optimality of the target sheet resistance value, avoiding suboptimal solutions due to local searches, and significantly improving compensation accuracy and optimization efficiency.

[0027] Example 3 This embodiment is the third embodiment of the liquid crystal lens aberration compensation method based on segmented high-resistivity layer electrodes. This embodiment is similar to Embodiment 1, except that in step S5, the first preset sheet resistance is 35 MΩ / sq, the second preset sheet resistance is 45 MΩ / sq, and the reference value is 40 MΩ / sq. These specific values ​​are the optimal parameter combinations determined through numerous simulation experiments. Parametric scanning within this sheet resistance range can cover the optimal solution range of the distortion-side resistance with high accuracy, while effectively controlling the scanning range to avoid unnecessary waste of computational resources.

[0028] In step S5, the scan step size for parametric scanning of the value to be adjusted is 0.5 MΩ / sq to 1 MΩ / sq. This step size range achieves a reasonable balance between optimization accuracy and computational efficiency: too large a step size may cause the target square resistance value to deviate from the true optimal solution, while too small a step size will significantly increase the simulation computation load without improving accuracy. Using this optimized step size can ensure the fine resolution of the target square resistance value to meet the strict requirements of high-quality imaging for wavefront accuracy, while also keeping the simulation time within a reasonable range, thus possessing good engineering practicality.

[0029] In step S6, the specific process for fabricating a high-resistivity layer electrode with at least two independent electrical regions is as follows: Differential deposition is performed on each electrical region on a glass substrate using mask sputtering or step-by-step deposition. By adjusting at least one process parameter among sputtering power, doping concentration, oxygen partial pressure, or deposition thickness, each electrical region obtains its corresponding target sheet resistance or reference value. This fabrication method eliminates the need for additional photolithography layers or complex post-processing steps. It utilizes existing, maturely applied technologies to achieve precise control of the sheet resistance of each region, exhibiting excellent process compatibility and mass production feasibility. Simultaneously, it avoids uncertainties and uniformity issues introduced by later adjustments.

[0030] like Figure 2 As shown, the structure of a traditional modally controlled liquid crystal lens, from top to bottom, consists of: an upper glass substrate, a circular aperture electrode, a high-resistivity layer electrode, an upper polyimide alignment layer (i.e., the upper PI layer), a liquid crystal layer, a lower polyimide alignment layer (i.e., the lower PI layer), a planar electrode, and a lower glass substrate. Both the circular aperture electrode and the planar electrode are made of indium tin oxide (ITO), a transparent conductive material. The high-resistivity layer electrode is a uniform, continuous thin film covering the entire lens aperture, with a constant sheet resistance within the aperture range. The upper and lower PI layers undergo reverse friction treatment to guide the liquid crystal molecules to align along a specific direction and impart a pretilt angle. When an AC driving voltage is applied between the circular aperture electrode and the planar electrode, a non-uniform electric field distribution is formed between the central and edge regions of the circular aperture electrode. This electric field, after being homogenized and smoothed by the high-resistivity layer electrode, acts on the liquid crystal layer, causing the liquid crystal molecules to tilt at spatially varying angles within the aperture, thereby forming a gradient refractive index distribution and achieving the lens effect. However, because the friction directions of the upper and lower PI layers are opposite, and the pretilt angles of the liquid crystal molecules on the left and right sides are opposite, under the drive of the electric field, the liquid crystal molecules on one side are more likely to deflect along the direction of the electric field, while the other side is relatively hindered, resulting in an asymmetric distortion of the refractive index distribution. For example... Figure 3 As shown, under the conditions of driving voltage of 1.8V and frequency of 3kHz, the actual refractive index distribution curve of the conventional modal control liquid crystal lens shows obvious local bulge in the left region relative to the ideal parabola. This asymmetric distortion directly leads to wavefront aberration, which is mainly astigmatism, and seriously affects the imaging quality.

[0031] like Figure 4As shown, the modal control liquid crystal lens structure used in this invention, from top to bottom, consists of: an upper glass substrate, a circular aperture electrode, a high-resistivity segmented electrode, an upper PI layer, a liquid crystal layer, a lower PI layer, a planar electrode, and a lower glass substrate. Compared to traditional structures, its core difference lies in the fact that the high-resistivity electrode is physically divided into independently electrically insulated electrical segments, specifically two electrically insulated segments, a first electrical segment and a second electrical segment, divided along the direction of liquid crystal molecule friction. The sheet resistance value of each electrical segment can be independently set according to compensation needs—the segment corresponding to the distortion side is assigned a target sheet resistance value after optimization, while the segment corresponding to the non-distortion side maintains a reference sheet resistance value. The materials of the circular aperture electrode and the planar electrode, the friction process of the PI layer, and the liquid crystal material system are all consistent with traditional solutions. During operation, the AC driving voltage applied between the circular aperture electrode and the planar electrode is transmitted to the liquid crystal layer through the segmented high-resistivity layer electrode. Due to the different sheet resistance values ​​of the high-resistivity layer electrodes on the left and right sides, the voltage drop from the edge of the circular aperture to the liquid crystal layer is different, which in turn causes the effective voltage above the liquid crystal layer on the left and right sides to be redistributed independently. By reasonably setting the sheet resistance value of the distorted side, the liquid crystal molecules on that side can obtain voltage compensation different from that on the non-distorted side, thereby effectively offsetting the difference in molecular deflection on both sides caused by the opposite pretilt angle direction, and making the refractive index distribution in the entire aperture range tend to be symmetrical.

[0032] In this embodiment, a two-dimensional simulation model containing liquid crystal material parameters, geometric structure parameters, and segmented high-resistivity layer electrodes was established using multiphysics coupling simulation software. The parameters are shown in Table 1.

[0033] Table 1 Simulation parameters of liquid crystal lens

[0034] In this embodiment, the lens achieves optimal overall optical performance when the left-side resistance is reduced from the standard 40 MΩ / sq to approximately 37 MΩ / sq. For example... Figure 5 As shown, after adopting a segmented high-resistivity layer electrode design and specifically optimizing the resistance value on the left side, the original... Figure 3 The localized bulge on the left side of the aperture was significantly suppressed, and the actual refractive index distribution curve essentially coincided with the ideal parabola across the entire aperture range, indicating that the asymmetric distortion had been effectively corrected. Figure 6 As shown, the phase difference curve exhibits a good quadratic parabolic shape in the range of 1.0D to 4.6D, indicating that the liquid crystal lens in this invention has continuous and effective electronically controlled focusing optical performance.

[0035] like Figure 7As shown, within a wide power range of 1.0D to 4.6D, the root mean square error of the wavefront of conventional lenses increases significantly with increasing power. However, the compensated lens of this invention maintains a low error level at all power levels, with an average error reduced by approximately 20.48% compared to conventional lenses, directly reflecting an overall improvement in the wavefront quality of the lens. Figure 8 As shown, the average peak-to-valley optical path difference of the lens of the present invention is significantly reduced by more than 23.44% compared with the traditional lens, indicating that the imaging clarity and consistency of the lens are significantly improved across the entire aperture range.

[0036] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0037] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for aberration compensation of a liquid crystal lens based on a segmented high-resistivity layer electrode, characterized in that, Includes the following steps: S1. Establish a simulation model of a modally controlled liquid crystal lens. The simulation model includes liquid crystal material parameters, lens geometric structure parameters, and high-resistivity layer electrode parameters. The high-resistivity layer electrode in the modally controlled liquid crystal lens is spatially divided into at least two independent electrical segments that are electrically insulated from each other. S2. Based on the simulation model, apply a driving voltage to the modally controlled liquid crystal lens and obtain the refractive index distribution curve; S3. Compare the refractive index distribution curve with the ideal parabolic refractive index distribution curve to identify the distortion side where the refractive index distribution curve undergoes a local abrupt change relative to the ideal parabolic distribution; S4. Set the sheet resistance value of the high-resistivity layer electrical section corresponding to the distorted side as the value to be adjusted, and maintain the sheet resistance value of the high-resistivity layer electrical section corresponding to the non-distorted side as the reference value. S5. Optimize the value to be adjusted to determine the target sheet resistance value that minimizes the deviation between the refractive index distribution curve and the ideal parabolic distribution. S6. Prepare high-resistivity layer electrodes having at least two independent electrical sections according to the target resistance value and the reference value respectively.

2. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 1, characterized in that, In step S1, the liquid crystal material parameters include pretilt angle, vertical dielectric constant, parallel dielectric constant, stretch elastic coefficient, torsional elastic coefficient, bending elastic coefficient, extraordinary light refractive index, ordinary light refractive index, and liquid crystal conductivity; the geometric structure parameters include lens radius, liquid crystal layer thickness, planar electrode thickness, circular hole electrode thickness, and glass substrate thickness; the high-resistivity layer electrode parameters include relative dielectric constant and sheet resistance.

3. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 1, characterized in that, The high-resistivity layer electrode is spatially divided into two electrically insulated sections, a first electrical section and a second electrical section, along the direction of liquid crystal molecule friction. The dividing line between the first electrical section and the second electrical section corresponds to the distortion inflection point of the refractive index distribution curve relative to the ideal parabolic distribution.

4. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 1, characterized in that, In step S2, the driving voltage is an AC voltage with an effective value of 1V to 3V and a frequency of 1kHz to 3kHz.

5. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 1, characterized in that, In step S3, the method for identifying the distorted side of the refractive index distribution curve that has a local abrupt change relative to the ideal parabolic distribution is as follows: draw the refractive index distribution curve and the ideal parabolic distribution curve in the same coordinate system, and determine the side that deviates from the ideal parabolic distribution and whose bulge exceeds a preset threshold by superimposing and comparing the curves.

6. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 1, characterized in that, In step S3, when there are three or more distortion regions in the lens aperture due to the refractive index distribution, the high-resistivity layer electrode is spatially divided into three or more electrically insulated electrical segments corresponding to the number of distortion regions, and the sheet resistance of each electrical segment can be adjusted independently.

7. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 1, characterized in that, In step S5, the method for optimizing the value to be adjusted to determine the target sheet resistance value is as follows: within the range of the first preset sheet resistance value to the second preset sheet resistance value, the sheet resistance value of the electrical section of the high-resistivity layer electrode corresponding to the distortion side is parametrically scanned, the root mean square error of the wavefront under each set of sheet resistance value conditions is calculated respectively, and the sheet resistance value corresponding to the minimum value of the root mean square error of the wavefront is determined as the target sheet resistance value.

8. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 7, characterized in that, In step S5, the first preset sheet resistance is 35 MΩ / sq, the second preset sheet resistance is 45 MΩ / sq, and the reference value is 40 MΩ / sq.

9. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 7, characterized in that, In step S5, the scan step size for parametric scanning of the value to be adjusted is 0.5 MΩ / sq to 1 MΩ / sq.

10. The aberration compensation method for a liquid crystal lens based on a segmented high-resistivity layer electrode according to claim 1, characterized in that, In step S6, the specific process for preparing a high-resistivity layer electrode with at least two independent electrical sections is as follows: using mask sputtering or step-by-step deposition, each electrical section is deposited differently on the glass substrate, and by adjusting at least one process parameter among sputtering power, doping concentration, oxygen partial pressure or deposition thickness, each electrical section obtains a corresponding target sheet resistance or reference value.

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