An optical field 3D display based on aspherical liquid crystal lens array

Abstract

This invention proposes a light field 3D display based on an aspherical liquid crystal lens array, comprising a 2D display screen and an aspherical liquid crystal lens array. The 2D display screen is used to display light field images. The aspherical liquid crystal lens array is used to control the light emitted by the 2D display screen to reproduce stereoscopic images. The aspherical liquid crystal lens array is driven by multiple AC power supplies, and the electric field distribution formed in the liquid crystal layer is aspherical. The liquid crystal molecules are affected by the electrode electric field, and the tilt angle of the liquid crystal molecules at different positions is different. The effective refractive index distribution of the aspherical liquid crystal lens array changes with the position of the liquid crystal molecules, and the effective refractive index conforms to the aspherical function distribution, realizing aspherical phase modulation and improving the clarity of the 3D display.

Description

Technical Field

[0001] This invention relates to the field of 3D display and liquid crystal technology, and more specifically, to a light field 3D display based on an aspherical liquid crystal lens array. Background Technology

[0002] Light field 3D display technology has attracted widespread attention for providing continuous spatial viewpoints and depth information, and is considered one of the most promising 3D display technologies. Liquid crystal lenses (LCDs) have excellent application prospects in the field of 3D display technology due to their advantages such as optical anisotropy, adaptive polarization sensitivity, zoom without mechanical movement, and lightweight structure. However, traditional LCDs often employ simplified single-electrode or aperture electrode structures, resulting in a relatively fixed gradient electric field distribution within the liquid crystal layer, which often only approximates a spherical phase distribution. Due to the limitations of the spherical wavefront, severe spherical aberration inevitably occurs in the lens edge region, limiting image sharpness. To overcome the limitations of existing technologies and achieve high-resolution and high-continuity light field 3D image reconstruction, it is urgent to develop a liquid crystal lens structure that can precisely control the local electric field through a multi-electrode array to achieve aspherical phase modulation, thereby compensating for aberrations at the source and improving imaging and display quality. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, this invention proposes a light field 3D display based on an aspherical liquid crystal lens array, including a 2D display screen, an aspherical liquid crystal lens array, and gradient voltage driving.

[0004] The 2D display screen is used to display light field images.

[0005] Preferably, the 2D display screen emits linearly polarized light.

[0006] The aspherical liquid crystal lens array is used to control the light emitted by the 2D display screen to reproduce stereoscopic images. The aspherical liquid crystal lens array consists of an upper substrate, an upper transparent planar electrode, an upper alignment layer, a liquid crystal layer, a lower alignment layer, a lower transparent rectangular electrode, and a lower substrate. The upper transparent planar electrode is made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The lower transparent rectangular electrode has the same thickness as the upper transparent planar electrode. The upper transparent planar electrode is grounded, and a voltage is applied to the lower transparent rectangular electrode. The angle between the long side of the lower transparent rectangular electrode and the long side of the lower substrate is θ. The friction direction between the lower alignment layer and the upper alignment layer is perpendicular to the long side of the lower transparent rectangular electrode.

[0007] Preferably, the friction direction of the upper and lower alignment layers is perpendicular to the long side direction of the transparent rectangular electrode.

[0008] Preferably, the liquid crystal layer is made of a low-viscosity nematic liquid crystal material, and the liquid crystal layer has a uniform thickness.

[0009] Preferably, the gap l of the lower transparent rectangular electrode is greater than or equal to 15 μm, and the width w is less than or equal to 15 μm.

[0010] Furthermore, the lower transparent rectangular electrode is composed of several groups of rectangular electrodes arranged periodically along the horizontal direction. Each K rectangular electrodes can be regarded as a rectangular electrode group, and the rectangular electrode groups are numbered from left to right as 1, 2, 3, ..., J-1, J, where J is an integer and K is an odd number.

[0011] Furthermore, in the rectangular electrode group, the rectangular electrodes are numbered 1, 2, 3, ..., K-1, K from left to right.

[0012] Furthermore, in the rectangular electrode group, the driving voltage of rectangular electrodes with different numbers is different. Let the origin be the coordinate system of the center point of the rectangular electrode numbered (K+1) / 2, and the positive x-axis be from left to right. The driving voltage V of the rectangular electrode numbered k is... k Calculated in the following way:

[0013] V k =V center +C1(x k / R) 2 + C2(x k / R) 4 +···+ C n (x k / R) 2n (1)

[0014] Among them, V center For the rectangular electrode numbered (K+1) / 2 corresponding to the center position of the lens unit, n is the aspherical order, C1, C2, ..., C n x is the aspherical coefficient. k Let R be the center coordinate of the k-th rectangular electrode, and R be the half-width of the lens unit.

[0015] Furthermore, in the rectangular electrode group, adjacent rectangular electrode groups share a single rectangular electrode. Attached Figure Description

[0017] The foregoing aspects and advantages of the present invention will become more apparent and readily understood from the following detailed description taken in conjunction with the accompanying drawings and embodiments, wherein:

[0018] Appendix Figure 1 This is a schematic diagram of the structure of a light field 3D display based on an aspherical liquid crystal lens array, provided as an embodiment of the present invention.

[0019] Appendix Figure 2This is a top view of the structure of an aspherical liquid crystal lens array for a light field 3D display based on an aspherical liquid crystal lens array, provided as an embodiment of the present invention.

[0020] Appendix Figure 3 This is a schematic diagram of a lens unit of an aspherical liquid crystal lens array for a light field 3D display based on an aspherical liquid crystal lens array, provided as an embodiment of the present invention.

[0021] Appendix Figure 4 The image provided in this embodiment of the invention is a simulation diagram of liquid crystal molecules in the lens unit of an aspherical liquid crystal lens array for a light field 3D display based on an aspherical liquid crystal lens array.

[0022] Appendix Figure 5 The effective refractive index simulation diagram of the lens unit of the aspherical liquid crystal lens array in a light field 3D display based on an aspherical liquid crystal lens array is provided for an embodiment of the present invention.

[0023] The reference numerals in the above figures are as follows: 1 2D display screen; 2 lower substrate of aspherical liquid crystal lens array; 3 lower alignment layer of aspherical liquid crystal lens array; 4 transparent rectangular electrode of aspherical liquid crystal lens array; 5 liquid crystal layer of aspherical liquid crystal lens array; 6 transparent planar electrode of aspherical liquid crystal lens array; 7 upper alignment layer of aspherical liquid crystal lens array; 8 upper substrate of aspherical liquid crystal lens array; 9 a group of rectangular electrodes in the aspherical liquid crystal lens array; 10 a group of rectangular electrodes in the aspherical liquid crystal lens array; 901 rectangular electrode numbered 1 in the rectangular electrode group; 902 rectangular electrode numbered 2 in the rectangular electrode group; 903 rectangular electrode numbered (K+1) / 2-1 in the rectangular electrode group; 904 rectangular electrode numbered (K+1) / 2 in the rectangular electrode group; 905 rectangular electrode numbered (K+1) / 2+1 in the rectangular electrode group; 906 rectangular electrode numbered K-1 in the rectangular electrode group; 907 rectangular electrode numbered K in the rectangular electrode group.

[0024] It should be understood that the above figures are only schematic and are not drawn to scale. Detailed Implementation

[0025] The following detailed description of an embodiment of a light field 3D display based on an aspherical liquid crystal lens array, as proposed in this invention, further illustrates the invention. The following embodiments are only for further illustrative purposes and should not be construed as limiting the scope of protection of this invention. Non-essential improvements and adjustments made to this invention by those skilled in the art based on the above description still fall within the scope of protection of this invention.

[0026] This invention proposes a 3D display based on an aspherical liquid crystal lens array, as shown in the attached figure. Figure 1 This includes 2D displays and aspherical liquid crystal lens arrays.

[0027] The 2D display screen is used to display light field images. In one embodiment, the 2D display screen is an LCD screen with a resolution of 3840×2160 pixels. The light emitted from the LCD screen is linearly polarized light.

[0028] The aspherical liquid crystal lens array is used to control the light emitted by the 2D display screen to reproduce stereoscopic images, as shown in the attached image. Figure 1 and attached Figure 2 As shown, the system includes a lower substrate 2, a lower alignment layer 3, a lower transparent rectangular electrode 4, a liquid crystal layer 5, an upper transparent planar electrode 6, an upper alignment layer 7, and an upper substrate 8. The lower transparent rectangular electrode 4 and the upper transparent planar electrode 6 are made of transparent conductive materials such as indium tin oxide (ITO) or indium zinc oxide (IZO); the lower transparent rectangular electrode 4 and the upper transparent planar electrode 6 have the same thickness; the upper transparent planar electrode 6 is grounded; the angle θ between the long side of the lower transparent rectangular electrode 4 and the long side of the lower substrate 2 is θ; the friction direction between the lower alignment layer 3 and the upper alignment layer 7 is perpendicular to the long side of the lower transparent rectangular electrode 4. In one embodiment, the angle θ between the long side of the lower transparent rectangular electrode 4 and the long side of the lower substrate 2 is 23°.

[0029] Preferably, the friction direction of the upper and lower alignment layers is perpendicular to the long side direction of the transparent rectangular electrode.

[0030] Preferably, the liquid crystal layer is made of a low-viscosity nematic liquid crystal material, and the liquid crystal layer has a uniform thickness. In one embodiment, the liquid crystal layer is made of E7 liquid crystal.

[0031] Preferably, the gap l of the lower transparent rectangular electrode is greater than or equal to 15 μm, and the width w is less than or equal to 15 μm. In one embodiment, the gap l of the lower transparent rectangular electrode is 15 μm, and the width w is 15 μm.

[0032] Furthermore, the lower transparent rectangular electrode is composed of several groups of rectangular electrodes arranged periodically along the horizontal direction. Each K rectangular electrodes can be regarded as a rectangular electrode group, and the rectangular electrode groups are numbered from left to right as 1, 2, 3, ..., J-1, J, where J is an integer and K is an odd number. In one embodiment, J is 360 and K is 15.

[0033] Furthermore, in the rectangular electrode group, the rectangular electrodes are numbered 1, 2, 3, ..., K-1, K from left to right.

[0034] Furthermore, to enable the liquid crystal lens array to perform aspherical phase modulation of the light emitted by the 2D display, different driving voltages are applied to the rectangular electrodes with different numbers in the rectangular electrode group, as shown in the attached figure. Figure 3As shown, let the origin be the center point of the rectangular electrode numbered (K+1) / 2, and let the positive x-axis be from left to right. Let the driving voltage V be numbered k. k Calculated in the following way:

[0035] V k =V center +C1(x k / R) 2 + C2(x k / R) 4 +···+ C n (x k / R) 2n ,

[0036] Among them, V center For the rectangular electrode numbered (K+1) / 2 corresponding to the center position of the lens unit, n is the aspherical order, C1, C2, ..., C n x is the aspherical coefficient. k Let V be the center coordinate of the k-th rectangular electrode, and R be the half-width of the lens unit. In one embodiment, V center The voltage is 1.7V, n is 3, C1 is 2.54, C2 is 0.82, C3 is 0.74, and R is 225μm.

[0037] Furthermore, in the rectangular electrode group, adjacent rectangular electrode groups share a single rectangular electrode.

[0038] This invention proposes a 3D display based on an aspherical liquid crystal lens array, the liquid crystal molecule results of the lens unit of the aspherical liquid crystal lens array are shown in the appendix. Figure 4 As shown, the liquid crystal molecules are affected by the electric field of the electrodes, and the tilt angle of the liquid crystal molecules at different positions is different, so that the effective refractive index distribution of the lens unit changes with the position of the liquid crystal molecules.

[0039] The present invention proposes a 3D display based on an aspherical liquid crystal lens array, and the simulation results of the effective refractive index of the lens unit of the aspherical liquid crystal lens array are attached. Figure 5 As shown, the liquid crystal molecules are affected by the electric field of the electrodes, and the effective refractive index distribution curve of the lens unit conforms to the parabolic function distribution, thus realizing aspherical phase modulation.

[0040] This invention utilizes an aspherical liquid crystal lens array for light field modulation, thereby achieving stereoscopic image display and improving the clarity of 3D displays.

[0041] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A light field 3D display based on an aspherical liquid crystal lens array, characterized in that, The display includes a 2D display screen and an aspherical liquid crystal lens array: The 2D display screen is used to display light field images; The aspherical liquid crystal lens array is used to control the light emitted by the 2D display screen to reproduce a stereoscopic image.

2. A light field 3D display based on an aspherical liquid crystal lens array according to claim 1, characterized in that, The aspherical liquid crystal lens array includes an upper substrate, an upper transparent planar electrode, an upper alignment layer, a liquid crystal layer, a lower alignment layer, a lower transparent rectangular electrode, and a lower substrate. The upper transparent planar electrode is grounded, and a voltage is applied to the lower transparent rectangular electrode. The angle between the long side of the lower transparent rectangular electrode and the long side of the lower substrate is θ. The friction direction between the lower alignment layer and the upper alignment layer is perpendicular to the long side direction of the lower transparent rectangular electrode.

3. A light field 3D display based on an aspherical liquid crystal lens array according to claim 1, characterized in that, The lower transparent rectangular electrode consists of several groups of rectangular electrodes arranged periodically along the horizontal direction; each group of K rectangular electrodes can be considered as a rectangular electrode group, numbered 1, 2, 3, ..., J-1, J from left to right, where J is an integer and K is an odd number; within each rectangular electrode group, the rectangular electrodes are numbered 1, 2, 3, ..., K-1, K from left to right. The driving voltage of rectangular electrodes with different numbers is different. Let the origin be the center point of the rectangular electrode numbered (K+1) / 2, and the positive x-axis be from left to right. The driving voltage V of the electrode numbered k is... k Calculated in the following way: V k =V center +C1(x k / R) 2 + C2(x k / R) 4 +···+ C n (x k / R) 2n , Among them, V center For the rectangular electrode numbered (K+1) / 2 corresponding to the center position of the lens unit, n is the aspherical order, C1, C2, ..., C n x is the aspherical coefficient. k Let R be the center coordinate of the k-th rectangular electrode, and R be the half-width of the lens unit.

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