Cholesteric liquid crystal display device and driving method for improving non-uniform image quality of cholesteric liquid crystal display device

Patent metadata

Field	Value
Publication number	US-11977302-B2
Application number	US-202218078079-A
Country	US
Kind code	B2
Filing date	Dec 8, 2022
Priority date	Dec 9, 2021
Publication date	May 7, 2024
Grant date	May 7, 2024

Abstract

A cholesteric liquid crystal display device and a driving method for improving non-uniform image quality of the cholesteric liquid crystal display device. The cholesteric liquid crystal display device includes a cholesteric liquid crystal display panel and a liquid crystal drive unit. The cholesteric liquid crystal display panel is composed of multiple row circuit structures and multiple column circuit structures. The liquid crystal driving unit sequentially outputs column driving voltages to a plurality of column circuit structures in a scanning manner. After scanning the multiple column circuit structures, the liquid crystal driving unit applies an unselected voltage to the multiple column circuit structures together with more than 18 times the scanning unit time course, so as to make the brightness of the overall picture more uniform.

First claim

What is claimed is:

1. A cholesteric liquid crystal display device, comprising:
a cholesteric liquid crystal display panel, comprising a plurality of column electrode lines (columns) and a plurality of row electrode lines (rows); and
a liquid crystal driving unit, electrically coupled to the cholesteric liquid crystal display panel and outputting column driving voltages to the column electrode lines, and applying row driving voltages to scan the row electrode lines in sequence, and taking a scan unit time to scan a row electrode line, and the row driving voltages comprising a select voltage and a non-select voltage;
wherein it takes more than eighteen (18) times of the scan unit time for the liquid crystal driving unit to address the row electrode lines by the non-select voltage after the row electrode lines are addressed by the liquid crystal driving unit.

2. The cholesteric liquid crystal display device according to claim 1 , wherein the cholesteric liquid crystal display panel is a Passive Matrix addressed cholesteric liquid crystal display panel.

3. A cholesteric liquid crystal display device, comprising:
a cholesteric liquid crystal display panel, comprising a plurality of column electrode lines (columns) and a plurality of row electrode lines (rows); and
a liquid crystal driving unit, electrically coupled to the cholesteric liquid crystal display panel and further comprising a control module, and outputting column driving voltages to the column electrode lines and applying row driving voltages to scan the row electrode lines in sequence, and taking a scan unit time to scan a row electrode line, and the row driving voltages comprising a select voltage and a non-select voltage;
wherein it takes a modification time increment for the control module to address the row electrode lines by the non-select voltage after the row electrode lines are addressed by the liquid crystal driving unit, and the modification time increment is more than eighteen times of the select unit times.

4. The cholesteric liquid crystal display device according to claim 3 , wherein the cholesteric liquid crystal display panel is a Passive Matrix addressed cholesteric liquid crystal display panel.

5. A driving method for improving non-uniform image quality of a cholesteric liquid crystal display device which has a liquid crystal driving unit and a cholesteric liquid crystal display panel which has a plurality of column electrode lines and a plurality of row electrode lines, the method comprising the steps of:
outputting column driving voltages to the column electrode lines while the row electrode lines are addressed by the row driving voltages in sequence, taking a scan unit time to scan a row electrode line, and the row driving voltage having a select voltage and a non-select voltage; and
taking a modification time increment more than eighteen times of the select unit times to address the row electrode lines by the non-select voltage after the row electrode lines are addressed by the liquid crystal driving unit.

6. The driving method according to claim 5 , wherein the cholesteric liquid crystal display panel is a Passive Matrix addressed cholesteric liquid crystal display panel.

Assignees

• Iris Optronics Co Ltd

Inventors

• Tsai Ming-Liang
• Yang Wu-Chang
• Liao Chi-Chang

Classifications

• G02F1/134309 Primary

  characterised by their geometrical arrangement · CPC title

• G02F1/13306

  Circuit arrangements or driving methods for the control of single liquid crystal cells (G02F1/132, G02F1/133382 take precedence) · CPC title

• G02F1/137

  characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering · CPC title

• G02F1/1391

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

• G09G3/3622 Primary

  using a passive matrix (G09G3/3674 - G09G3/3696 take precedence) · CPC title