Liquid crystal display and organic EL display

• US 8,212,970 B2
• Filed: 10/09/2008
• Issued: 07/03/2012
• Est. Priority Date: 10/10/2007
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated), Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Inventors: Nagata, Tetsuya
• Primary Examiner(s): Kim, Richard
• Assistant Examiner(s): CHUNG, DAVID Y
• Application Number:
  US12/285,603
• Publication Number:
  US 20090096965A1
• Time in Patent Office: 1,363 Days
• Field of Search: 349/96, 349158-160
• US Class Current: 349/96
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: H04M 1/0202 Portable telephone sets, e.g. cordless phones, mobile phones or bar type handsets constructional features of telephone transmitters or receivers, e.g. of speakers or microphones H04M1/03
• CPC Class Codes: H10K 2102/311 Flexible OLED
• CPC Class Codes: H10K 50/86 Arrangements for improving contrast, e.g. preventing reflection of ambient light
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/8791 Arrangements for improving contrast, e.g. preventing reflection of ambient light

Abstract

Disclosed is a liquid display device that is capable of suppressing a change in contrast of a liquid crystal display panel, in which a screen is a curved surface with a curvature in one direction. In a liquid crystal display panel having a cylindrical surface, an upper polarizing plate is attached to a color filter substrate. The upper polarizing plate receives tensile stress in a curved direction. Tensile stress adversely affects polarization characteristics of the upper polarizing plate. According to an embodiment of the invention, if the absorption axis A of the upper polarizing plate is adapted to match with the curved direction of the liquid crystal display panel, it is possible to prevent a change in polarization characteristics of the upper polarizing plate. As a result, it is possible to obtain an image with excellent contrast for a long term.

Claims

1. A liquid crystal display comprising:

a liquid crystal display panel, the liquid crystal display panel including a TFT substrate having formed thereon pixel electrodes and TFTs, a color filter substrate having formed thereon color filters, liquid crystal interposed between the color filter substrate and the TFT substrate, a first polarizing plate attached to the color filter substrate, and a second polarizing plate attached to the TFT substrate,

wherein the liquid crystal display panel has an outwardly convex screen with a curvature in one direction, and the first polarizing plate substantially has an absorption axis in a direction in which the liquid crystal display panel has a curvature, and

an angle between an axis in the direction, in which the liquid crystal display panel has a curvature, and the absorption axis of the first polarizing plate is 10±

5 degrees.

2. The liquid crystal display according to claim 1,

wherein the absorption axis of the second polarizing plate and a direction perpendicular to that in which the liquid crystal display panel has a curvature is 10±

5 degrees.

3. A liquid crystal display comprising:

a liquid crystal display panel, the liquid crystal display panel including a TFT substrate having formed thereon pixel electrodes and TFTs, a color filter substrate having formed thereon color filters, liquid crystal interposed between the color filter substrate and the TFT substrate, a first polarizing plate attached to the color filter substrate, and a second polarizing plate attached to the TFT substrate,

wherein the liquid crystal display panel has an outwardly concave screen with a curvature in one direction, and an angle between the absorption axis of the first polarizing plate and a direction perpendicular to that in which the liquid crystal display panel has a curvature is 10±

5 degrees.

4. The liquid crystal display according to claim 3,

wherein an angle between the absorption axis of the second polarizing plate and the direction in which the liquid crystal display panel has a curvature is 10±

5 degrees.