Laminated optical film, method for producing the same film and liquid-crystal display device using the same film

• US 20020196397A1
• Filed: 06/05/2002
• Published: 12/26/2002
• Est. Priority Date: 06/07/2001
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.), Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Ashida, Takeyuki, Imai, Takio, Sugiura, Shoji, Takahashi, Naoki, Kawahara, Satoru
• Granted Patent: US 6,661,487 B2
• Time in Patent Office: Days
• US Class Current: 349/115
• CPC Class Codes: G02F 1/1335 Structural association of cells with optical devices, e.g. polarisers or reflectors
• CPC Class Codes: G02F 1/133507 Films for enhancing the luminance
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 2202/28 Adhesive materials or arrangements

Abstract

A method of producing a laminated optical film constituted by a laminate of a plurality of optical films different in area, the method including the steps of: laminating an optical film (B) having a plurality of rectangular holes parallel to one another, on at least one surface of an optical film (A) to thereby form a laminate; and cutting the laminate into a plurality of chips to thereby obtain laminated optical films.

Claims

1. A method of producing a laminated optical film constituted by a laminate of a plurality of optical films different in area, said method comprising steps of:

laminating a second optical film having a plurality of rectangular holes parallel to one another, on at least one surface of a first optical film to thereby form a laminate; and

cutting said laminate into a plurality of chips.

2. A method of producing a laminated optical film according to claim 1, wherein said first optical film is a polarizer whereas said second optical film is a luminance-enhancement film.

3. A method of producing a laminated optical film according to claim 1, wherein said first optical film is an optical film including at least one retardation film or viewing angle compensating film laminated on a surface opposite to a surface through which said first optical film is stuck onto said second optical film.

4. A method of producing a laminated optical film according to claim 1, wherein said second optical film is an optical film constituted by a combination of cholesteric liquid crystal and λ

/4 plate.

5. A method of producing a laminated optical film according to claim 1, wherein said first optical film and said second optical film are laminated on each other through a pressure sensitive adhesive.

6. A laminated optical film produced by a method according to claim 1, said laminated optical film having extruded portions formed from said first optical film, said laminated optical film having at least one side surface cut in a plane.

7. A liquid-crystal display device comprising a liquid-crystal cell, and at least one laminated optical film according to claim 6 and disposed on at least one surface of said liquid-crystal cell.

8. A liquid-crystal display device according to claim 7, wherein at least one of said extruded portions of said laminated optical film is stuck onto a surface light source through a double-sided adhesive tape.