Liquid crystal handwriting board and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-12379630-B2
Application number	US-202218019244-A
Country	US
Kind code	B2
Filing date	Jan 29, 2022
Priority date	Jan 29, 2022
Publication date	Aug 5, 2025
Grant date	Aug 5, 2025

Abstract

Provided is a liquid crystal handwriting board. The liquid crystal handwriting board includes a first substrate, a second substrate, a third substrate, a first liquid crystal layer, and a second liquid crystal layer; wherein the first substrate includes: a first base, and a first pixel electrode and a transparent electrode, wherein the first pixel electrode is insulated from the transparent electrode, and the first pixel electrode is closer to the second substrate than the transparent electrode is; wherein the first substrate, the first liquid crystal layer and the second substrate are configured to form a display portion of the liquid crystal handwriting board; and the first substrate, the second liquid crystal layer and the third substrate are configured to form a writing portion of the liquid crystal handwriting board.

First claim

What is claimed is:

1. A liquid crystal handwriting board, comprising: a first substrate, a second substrate disposed on a side of the first substrate, a third substrate disposed on a side of the first substrate away from the second substrate, a first liquid crystal layer disposed between the first substrate and the second substrate, and a second liquid crystal layer disposed between the first substrate and the third substrate; wherein
the first substrate comprises: a first base, and a first pixel electrode and a transparent electrode that are disposed on a side of the first base close to the second substrate, wherein the first pixel electrode is insulated from the transparent electrode, and the first pixel electrode is closer to the second substrate than the transparent electrode is;
wherein the first substrate, the first liquid crystal layer and the second substrate are configured to form a display portion of the liquid crystal handwriting board; and the first substrate, the second liquid crystal layer and the third substrate are configured to form a writing portion of the liquid crystal handwriting board;
wherein the transparent electrode is a shield electrode, and the first substrate further comprises a second pixel electrode disposed on a side of the transparent electrode close to the first base, wherein the second pixel electrode is insulated from the transparent electrode;
wherein a plurality of first pixel electrodes and a plurality of second pixel electrodes are provided, wherein one of the second pixel electrodes corresponds to at least one of the first pixel electrodes; and
wherein an orthographic projection of the first pixel electrode on the first base is within an orthographic projection of the corresponding second pixel electrode on the first base.

2. The liquid crystal handwriting board according to claim 1 , wherein the first substrate further comprises a first thin film transistor electrically connected to the first pixel electrode, and a second thin film transistor electrically connected to the second pixel electrode, wherein the first thin film transistor and the second thin film transistor are disposed in a same layer.

3. The liquid crystal handwriting board according to claim 2 , wherein the second thin film transistor is disposed between the first pixel electrode and the transparent electrode, the transparent electrode is provided with a first via hole, and a first electrode of the second thin film transistor passes through the first via hole to be electrically connected to the second pixel electrode.

4. The liquid crystal handwriting board according to claim 3 , wherein the first substrate further comprises: a first insulating layer disposed between the second pixel electrode and the transparent electrode, and a second insulating layer disposed between the second thin film transistor and the transparent electrode, wherein the first insulating layer is provided with a second via hole in communication with the first via hole, and the second insulating layer is provided with a third via hole in communication with the first via hole;
wherein an orthographic projection of the second via hole on the first base and an orthographic projection of the third via hole on the first base are both within an orthographic projection of the first via hole on the first base, and the first electrode of the second thin film transistor sequentially passes through the third via hole, the first via hole and the second via hole to be electrically connected to the second pixel electrode.

5. The liquid crystal handwriting board according to claim 2 , wherein the first substrate further comprises: a plurality of first gate lines and a plurality of first data lines that are electrically connected to a plurality of first thin film transistors, and a plurality of second gate lines and a plurality of second data lines that are electrically connected to a plurality of second thin film transistors; wherein
an orthographic projection of one of the first gate lines on the first base is between the orthographic projections of two adjacent rows of first pixel electrodes on the first base; and an orthographic projection of one of the first data lines on the first base is between the orthographic projections of two adjacent columns of first pixel electrodes on the first base; and
an orthographic projection of one of the second gate lines on the first base is between the orthographic projections of two adjacent rows of second pixel electrodes on the first base; and an orthographic projection of one of the second data lines on the first base is between the orthographic projections of two adjacent columns of second pixel electrodes on the first base;
wherein the orthographic projection of one of the first gate lines on the first base and the orthographic projection of one of the second gate lines on the first base are simultaneously between the orthographic projections of two adjacent rows of second pixel electrodes on the first base; and
wherein the orthographic projection of one of the first data lines on the first base and the orthographic projection of one of the second data lines on the first base are simultaneously between the orthographic projections of two adjacent columns of second pixel electrodes on the first base.

6. The liquid crystal handwriting board according to claim 5 , wherein the first gate line and the second gate line are disposed in a same layer and made from a same material; and the first data line and the second data line are disposed in a same layer and made from a same material.

7. The liquid crystal handwriting board according to claim 1 , wherein the third substrate comprises: a flexible base, and a first common electrode disposed on a side of the flexible base close to the second liquid crystal layer.

8. The liquid crystal handwriting board according to claim 1 , wherein the transparent electrode is a common electrode of the writing portion, and the third substrate comprises: a flexible base, and a drive electrode disposed on a side of the flexible base close to the second liquid crystal layer.

9. The liquid crystal handwriting board according to claim 8 , wherein an insulating layer is disposed between the first pixel electrode and the transparent electrode, and the first pixel electrode, the transparent electrode and the insulating layer are configured to form a storage capacitor.

10. The liquid crystal handwriting board according to claim 1 , wherein liquid crystal molecules in the second liquid crystal layer are bistable liquid crystal molecules;
wherein the bistable liquid crystal molecules in the second liquid crystal layer are configured to: transition from a focal conic texture to a planar texture after the third substrate is subjected to external pressure; and transition from the planar texture to the focal conic texture after an electric field is formed between the first substrate and the third substrate.

11. The liquid crystal handwriting board according to claim 1 , further comprising: a first polarizer and a transflective film, wherein the first liquid crystal layer is disposed between the first polarizer and the transflective film, and the transflective film is disposed on a side of the first liquid crystal layer away from the first substrate;
wherein the transflective film is configured to transmit first polarized light with a polarization direction parallel to a polarization direction of the first polarizer, and reflect second polarized light with a polarization direction perpendicular to the polarization direction of the first polarizer.

12. The liquid crystal handwriting board according to claim 11 , further comprising: a light absorbing layer dispose

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Optoelectronics Tech Co Ltd
• Shandong Lanbeisite Educational Equipment Group

Inventors

• Wang Jiaxing
• Wang Jian
• Wu Xiaojuan
• Yuan Hongliang
• Wang Xiuliang
• Bi Yao
• Duan Jinshuai
• Liu Feng
• Chen Cuiyu
• Ge Yang
• Duan Zhilong
• Yu Zhiqiang
• Han Tianyang

Classifications

• G02F1/1362

  Active matrix addressed cells {(G02F1/134336, G02F1/134363 take precedence)} · CPC title

• G02F1/1333

  Constructional arrangements; {Manufacturing methods}(G02F1/135, G02F1/136 take precedence) · CPC title

• G02F1/1391

  Bistable or multi-stable liquid crystal cells (G02F1/141 takes precedence) · CPC title

• G02F1/1368

  in which the switching element is a three-electrode device {(G02F1/136277 takes precedence)} · CPC title

• G02F1/13439

  characterised by their electrical, optical, physical properties; materials therefor; method of making · CPC title