Apparatus and method for injecting liquid crystal material

• US 6,611,314 B1
• Filed: 11/02/2000
• Issued: 08/26/2003
• Est. Priority Date: 11/17/1999
• Status: Expired due to Term

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Choi, Su-Seok, Kim, Yong-Bum
• Primary Examiner(s): DUDEK, JAMES A
• Application Number:
  US09/703,626
• Time in Patent Office: 1,027 Days
• Field of Search: 349/189, 349/133, 349/124
• US Class Current: 349/189
• CPC Class Codes: G02F 1/1341 Filling or closing of cells

Abstract

A liquid crystal injection apparatus and method for injecting a liquid crystal material between substrates of a liquid crystal display panel. The method and apparatus includes using an electric field to orientate the liquid crystal material during injection such that the liquid crystal material has a reduced viscosity. The electric field can be produced by electrodes adjacent the substrates, and by an electric source that applies a potential to the electrodes. Liquid crystal material injection can be the result of capillary forces and/or differential pressure.

Claims

1. A method of injecting liquid crystal material inside a liquid crystal cell having an injection port, and a gap between a first substrate and a second substrate, wherein each substrate include an orientation film, the method comprising;

inducing an electric field within the liquid crystal cell such that said electric field is substantially normal to said first substrate and to said second substrate; and

injecting a liquid crystal material through the injection port and into the gap between the first and second substrates,

wherein the electric field is induced by locating the first substrate and the second substrate between a first electrode and a second electrode and by applying a potential between the first electrode and the second electrode.

2. A method of injecting liquid crystal material inside a liquid crystal cell having an injection port, and a gap between a first substrate and a second substrate, the method comprising;

locating the liquid crystal cell inside a vacuum chamber;

evacuating the vacuum chamber and the liquid crystal cell;

inducing an electric field within the liquid crystal cell such that said electric field is substantially normal to said first substrate and to said second substrate; and

dipping the injection port into a liquid crystal material,

wherein the electric field is induced by locating the first substrate and the second substrate between a first electrode and a second electrode and by applying a potential between the first electrode and the second electrode.

3. A method according to claim 2, further including the step of increasing the pressure inside of said vacuum chamber such that a pressure differential between the interior of said liquid crystal cell and the exterior of said liquid crystal cell forces liquid crystal material into the liquid crystal cell.

4. A method according to claim 2, wherein the step of applying a potential between the first electrode and the second electrode applies a DC potential between the first electrode and the second electrode.

5. A method according to claim 2, wherein the step of applying a potential between the first electrode and the second electrode applies an AC potential between the first electrode and the second electrode.

6. A method of injecting liquid crystal material inside a liquid crystal cell having an injection port and a gap between a first substrate and a second substrate, wherein the first substrate and the second substrate each have an orientation film, the method comprising the steps of;

locating the liquid crystal cell inside a vacuum chamber;

evacuating the vacuum chamber and the liquid crystal cell;

inducing an electric field within the liquid crystal cell such that said electric field is substantially parallel to the orientation of said orientation film; and

contacting the injection port with a liquid crystal material.

7. A method according to claim 6, further including the step of increasing the pressure within the vacuum chamber such that a pressure differential is created between the interior of the liquid crystal cell and the exterior of the liquid crystal cell, wherein the pressure differential forces liquid crystal material into the liquid crystal cell.

8. A method according to claim 7, wherein the step of increasing the pressure within the vacuum chamber includes the step of filling the vacuum chamber with a gas.

9. A method according to claim 8, wherein nitrogen fills the vacuum chamber.

10. A method according to claim 7, wherein the step of inducing an electric field within the liquid crystal cell includes the steps of:

locating the first substrate and the second substrate between a first electrode and a second electrode; and

applying a potential between the first electrode and the second electrode.

11. A method according to claim 10, wherein the step of applying a potential between the first electrode and the second electrode applies a DC potential between the first electrode and the second electrode.

12. A method according to claim 10, wherein the step of applying a potential between the first electrode and the second electrode applies an AC potential between the first electrode and the second electrode.