A liquid crystal lens array based on a hollow electrode

Abstract

The application provides a liquid crystal lens array based on a hollow electrode, which comprises an upper substrate, an upper hollow island-shaped electrode, an upper orientation layer, a liquid crystal layer, a lower orientation layer, a lower hollow rectangular electrode, a lower substrate and a wire. When the upper hollow island-shaped electrode is grounded and an alternating voltage is applied to the lower hollow rectangular electrode, a spatial non-uniform electric field is formed in the liquid crystal layer, the nematic liquid crystal molecules in the liquid crystal layer are deflected to different degrees under the action of the non-uniform electric field, a gradient refractive index distribution is formed, and an optical focusing effect is realized.

Description

Technical Field

[0001] This invention relates to the fields of liquid crystal technology and touch interaction technology, and more specifically, to a liquid crystal lens array based on hollowed-out electrodes. Background Technology

[0002] Liquid crystal lens arrays offer advantages such as electronically controlled zoom, no mechanical movement, and lightweight structure, making them widely used in fields such as 3D displays and light field manipulation. Typically, liquid crystal lens arrays have continuous transparent conductive electrodes on the inner sides of the upper and lower substrates. By applying a voltage to the electrodes, a non-uniform electric field is formed in the liquid crystal layer, driving the liquid crystal molecules to deflect and generate a gradient refractive index distribution.

[0003] However, continuous conductive electrode layers form a complete electric field shielding surface. When a liquid crystal lens array is integrated with a capacitive touchscreen, the touch detection electric field is completely shielded, leading to touch failure. Simultaneously, continuous electrodes also reduce light transmittance. To address these issues while maintaining lens performance, researchers both domestically and internationally have proposed various perforated electrode structures, such as mesh-perforated electrodes, metal mesh electrodes, and strip or island-shaped electrode patterns. However, with these solutions, excessively high perforation ratios result in decreased driving efficiency and increased aberrations, while excessively low perforation ratios restrict touch penetration and easily generate moiré fringes, making it difficult to balance touch compatibility, light transmittance, and lens imaging quality. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, this invention proposes a liquid crystal lens array based on hollowed-out electrodes, including an upper substrate, an upper hollowed-out island electrode, an upper alignment layer, a liquid crystal layer, a lower alignment layer, a lower hollowed-out rectangular electrode, a lower substrate, and conductive wires.

[0005] The upper and lower substrates are made of glass and are used to encapsulate and fix the liquid crystal layer and the carrier electrode.

[0006] The upper hollowed-out island-shaped electrode is composed of several rectangular electrodes arranged in two-dimensional rows and columns, and is made of transparent conductive materials such as indium tin oxide (ITO) or indium zinc oxide (IZO); hollow areas are formed between the rectangular electrodes; the rectangular electrodes are connected in pairs by wires to maintain equipotential.

[0007] The lower hollow rectangular electrode is composed of several orthogonally and uniformly arranged rectangular electrodes, and is made of transparent conductive materials such as indium tin oxide (ITO) or indium zinc oxide (IZO); hollow areas are formed between the rectangular electrodes.

[0008] Furthermore, the upper hollowed-out island-shaped electrode and the lower hollowed-out rectangular electrode have the same thickness.

[0009] Furthermore, the upper hollow island-shaped electrode is grounded, and voltage is applied to the lower hollow rectangular electrode.

[0010] Furthermore, the geometric center of the rectangular electrode in the upper hollowed-out island electrode is aligned with the geometric center of the hollowed-out gap in the lower hollowed-out rectangular electrode in the vertical direction.

[0011] Furthermore, the liquid crystal layer is made of a low-viscosity nematic liquid crystal material.

[0012] Furthermore, the friction direction between the upper and lower alignment layers is parallel to the long side direction of the lower substrate.

[0013] Preferably, the gap between the rectangular electrodes in the upper hollowed-out island electrode is less than or equal to 100 μm, and the line width of the conductor between the rectangular electrodes is greater than or equal to 0.5 μm and less than or equal to 10 μm.

[0014] Preferably, the gap between the rectangular electrodes in the lower hollow rectangular electrode is greater than or equal to 150 μm, and the width of the rectangular electrode is less than or equal to 15 μm.

[0015] The working principle of the liquid crystal lens array is as follows: the upper hollowed-out island electrode is grounded, and a voltage is applied to the lower hollowed-out rectangular electrode, forming a spatially non-uniform electric field in the liquid crystal layer. The nematic liquid crystal molecules in the liquid crystal layer are deflected to different degrees under the action of the non-uniform electric field, forming a gradient refractive index distribution, thus achieving an optical focusing effect. When the liquid crystal lens array is stacked above a capacitive touchscreen, the touch detection electric field emitted by the touchscreen passes sequentially through the gap between the lower hollowed-out rectangular electrode and the gap between the upper hollowed-out island electrode, reaches the touch object, and is fed back to the touch chip, realizing the touch function. Attached Figure Description

[0016] 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:

[0017] Appendix Figure 1 This is a cross-sectional structural diagram of a liquid crystal lens array provided in an embodiment of the present invention.

[0018] Appendix Figure 2 This is a top view of the hollowed-out island-shaped electrode provided in an embodiment of the present invention.

[0019] Appendix Figure 3 A top view of the hollowed-out rectangular electrode provided in an embodiment of the present invention.

[0020] Appendix Figure 4 This is a schematic diagram showing the relative positions of the upper hollowed-out island-shaped electrode and the lower hollowed-out rectangular electrode.

[0021] Appendix Figure 5 This is a simulation diagram of the effective refractive index distribution of a liquid crystal lens array based on hollowed-out electrodes.

[0022] The reference numerals in the above figures are: 1 Upper substrate, 2 Upper hollowed-out island electrode, 3 Upper alignment layer, 4 Liquid crystal layer, 5 Lower alignment layer, 6 Lower hollowed-out rectangular electrode, 7 Lower substrate, 8 Conductor.

[0023] It should be understood that the above figures are only schematic and are not drawn to scale. Detailed Implementation

[0024] The following detailed description of an embodiment of a liquid crystal lens array based on hollowed-out electrodes 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.

[0025] This invention proposes a liquid crystal lens array based on hollowed-out electrodes, as shown in the attached figure. Figure 1 It includes an upper substrate 1, an upper hollowed-out island electrode 2, an upper alignment layer 3, a liquid crystal layer 4, a lower alignment layer 5, a lower hollowed-out rectangular electrode 6, a lower substrate 7, and a wire 8.

[0026] The upper substrate 1 and the lower substrate 7 are made of glass and are used to encapsulate and fix the liquid crystal layer and the carrier electrode. In one embodiment, the thickness of both the upper substrate 1 and the lower substrate 7 is 50 μm.

[0027] As attached Figure 2 As shown, the upper hollowed-out island electrode 2 is composed of several rectangular electrodes arranged in a uniform two-dimensional row and column, and is made of indium tin oxide (ITO) transparent conductive material; hollow areas are formed between the rectangular electrodes; the rectangular electrodes are connected in pairs by wires 8 to maintain equipotential. In one embodiment, the rectangular electrodes in the upper hollowed-out island electrode 2 are square.

[0028] As attached Figure 3 As shown, the lower hollow rectangular electrode 6 is composed of several orthogonally and uniformly arranged rectangular electrodes, and is made of indium tin oxide (ITO) transparent conductive material; hollow areas are formed between the rectangular electrodes.

[0029] Furthermore, the upper hollowed-out island-shaped electrode 2 and the lower hollowed-out rectangular electrode 6 have the same thickness. In one embodiment, the thickness of both the upper hollowed-out island-shaped electrode 2 and the lower hollowed-out rectangular electrode 6 is 0.04 μm.

[0030] Furthermore, the upper hollowed-out island-shaped electrode 2 is grounded, and a voltage is applied to the lower hollowed-out rectangular electrode 6. In one embodiment, the applied voltage is an AC voltage with an amplitude of 20V (RMS) and a frequency of 1kHz.

[0031] Furthermore, as shown in the appendix Figure 4As shown, the geometric center of the rectangular electrode in the upper hollowed-out island electrode 2 is aligned with the geometric center of the hollowed-out gap in the lower hollowed-out rectangular electrode 6 in the vertical direction.

[0032] Furthermore, the liquid crystal layer 4 is made of a low-viscosity nematic liquid crystal material. In one embodiment, the liquid crystal layer 4 is made of E7 liquid crystal.

[0033] Furthermore, the friction direction between the upper alignment layer 3 and the lower alignment layer 5 is parallel to the long side direction of the lower substrate.

[0034] Preferably, the gap between the rectangular electrodes in the upper hollowed-out island electrode 2 is less than or equal to 100 μm, and the linewidth of the conductor between the rectangular electrodes is greater than or equal to 0.5 μm and less than or equal to 10 μm. In one embodiment, the gap between the rectangular electrodes is 55 μm, and the linewidth of the conductor 8 between the rectangular electrodes is 2 μm.

[0035] Preferably, the gap between the rectangular electrodes in the lower hollowed-out rectangular electrode 6 is greater than or equal to 150 μm, and the width of the rectangular electrode is less than or equal to 15 μm. In one embodiment, the gap between the rectangular electrodes is 435 μm.

[0036] The specific implementation process of the liquid crystal lens array based on hollowed-out electrodes provided by the present invention is as follows:

[0037] The upper hollowed-out island-shaped electrode 2 is grounded, and an AC voltage is applied to the lower hollowed-out rectangular electrode 6. Because both the upper and lower electrodes have hollowed-out gaps, a spatially non-uniform electric field is formed in the liquid crystal layer 4. (See attached diagram) Figure 5 As shown, the nematic liquid crystal molecules in the liquid crystal layer 4 are deflected to different degrees under the action of a non-uniform electric field. The deflection angle is larger where the electric field is stronger and smaller where the electric field is weaker, thus forming a gradient refractive index distribution and achieving an optical focusing effect. When the liquid crystal lens array is stacked above the capacitive touch screen, the touch detection electric field emitted by the touch screen passes sequentially through the gap between the lower hollow rectangular electrode 6 and the upper hollow island electrode 2, reaches the touch body, and is fed back to the touch chip to realize the touch function.

[0038] 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 liquid crystal lens array based on hollowed-out electrodes, characterized in that, The device includes an upper substrate, an upper hollowed-out island electrode, an upper alignment layer, a liquid crystal layer, a lower alignment layer, a lower hollowed-out rectangular electrode, a lower substrate, and conductive wires. The upper hollowed-out island electrode is composed of several rectangular electrodes arranged in a uniform two-dimensional row and column. Hollow areas are formed between the rectangular electrodes. The rectangular electrodes are connected in pairs by conductive wires to maintain equipotential. The lower hollowed-out rectangular electrode is composed of several orthogonally and uniformly arranged rectangular electrodes. Hollow areas are formed between the rectangular electrodes.

2. The liquid crystal lens array based on hollowed-out electrodes according to claim 1, characterized in that, The upper hollow island-shaped electrode is grounded, and voltage is applied to the lower hollow rectangular electrode; the geometric center of the rectangular electrode in the upper hollow island-shaped electrode and the geometric center of the hollow gap in the lower hollow rectangular electrode are aligned in the vertical direction.

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