Liquid-crystal display and a lighting apparatus

• US 6,847,424 B2
• Filed: 08/23/2001
• Issued: 01/25/2005
• Est. Priority Date: 02/09/2001
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Fujitsu Display Technologies Corporation (Fujitsu Limited)
• Inventors: Hayashi, Keiji, Suzuki, Toshihiro, Hamada, Tetsuya, Kobayashi, Tetsuya, Gotoh, Takeshi
• Primary Examiner(s): Flynn, Nathan J.
• Assistant Examiner(s): Sefer, Ahmed N.
• Application Number:
  US09/938,183
• Publication Number:
  US 20020154256A1
• Time in Patent Office: 1,251 Days
• Field of Search: 349/113, 349/117, 349/61, 349/63, 349/137
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side

Abstract

A liquid-crystal display includes a reflective liquid-crystal panel, a light guiding plate disposed on the reflective liquid-crystal panel, a polarizer arranged between a liquid-crystal layer of the reflective liquid-crystal panel and the light guiding plate, and a light source disposed on a side surface of the light guiding plate. Light emitted from the light source propagates through the light guiding plate and has a primary direction. A smaller one of two angles between a projection of the primary direction onto the reflective liquid-crystal panel and an absorption axis of the light guiding plate is at least 50°. This resultantly improves performance of the liquid-crystal display.

Claims

1. A reflective liquid-crystal display, comprising:

a lighting apparatus, comprising;

a light guiding plate including a flat first surface having a plurality of projections, each said projection being formed with a first inclined plane having a first angle between said plane and said flat first surface and with a second inclined plane formed adjacent to said first inclined plane with a second angle between said plane and said flat first surface, said second angle being larger than said first angle and

a light source directly coupled to a side surface of said light guiding plate;

a reflective liquid-crystal panel disposed on a second surface of said light guiding plate, said second surface opposing said first surface, said reflective liquid-crystal panel opposing said first surface;

a polarizer disposed between said reflective liquid-crystal panel and said light guiding plate, said polarizer being directly in contact with said reflective liquid crystal panel;

a low-refractive-index layer formed between said polarizer and said light guiding plate, said low-refractive-index layer having a refractive index smaller than a refractive index of said light guiding plate; and

another low-refractive-index layer covering said plurality of projections, and having a refractive index smaller than that of the light guiding plate.

2. A reflective liquid-crystal display according to claim 1, wherein said low-refractive-index layer is formed using a fluorine-based resin or a fluorine-based liquid.

3. A reflective liquid crystal display according to claim 1, wherein said low-refractive-index layer has a refractive index of 1.2 to 1.4.

4. A reflective liquid crystal display according to claim 1, wherein said another low-refractive-index layer has a refractive index of 1.2 to 1.4.

5. A reflective liquid crystal display according to claim 1, wherein said another low-refractive-index layer is directly in contact with said low-refractive-index layer.

6. A reflective liquid crystal display according to claim 1, further comprising an optical adhesive agent layer disposed between said low-refractive-index layer and said polarizer.