Liquid crystal display

• US 5,467,208 A
• Filed: 06/01/1993
• Issued: 11/14/1995
• Est. Priority Date: 06/01/1992
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Nishihara, Michiharu, Sato, Yukikazu, Kokawa, Shozo
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US08/069,392
• Time in Patent Office: 896 Days
• Field of Search: 359/48, 359/49, 359/50, 359/42, 359/66, 359/69, 359/49, 359/40, 362/339, 362/26, 362/31, 385/901, 385/146
• US Class Current: 349/67
• CPC Class Codes: F21V 5/02 of prismatic shape F21V5/04 takes precedence
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0071 with elongated shape, e.g. tube
• CPC Class Codes: G02B 6/0088 of the light guide or other optical sheets in the package
• CPC Class Codes: G02B 6/009 of the light source in the package G02B6/0021 takes precedence
• CPC Class Codes: G02F 1/133374 for displaying permanent signs or marks
• CPC Class Codes: G02F 1/133502 Antiglare, refractive index matching layers
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/13452 Conductors connecting driver circuitry and terminals of panels
• CPC Class Codes: Y10S 385/901 Illuminating or display apparatus

Abstract

A liquid crystal display including a sheet for converging light from a back light source. The sheet may be an array of truncated prisms, an array of prisms separated by flat portions, asymmetrical prisms with dual vertices, or prisms with different vertices.

Claims

1. A liquid crystal display comprising;

display means for displaying characters and graphics, said display means including a display portion comprising at least a liquid crystal panel including a plurality of picture elements and having a predetermined viewing angle in a front axial direction perpendicular to said panel;

illuminating means for illuminating the display portion of the liquid crystal panel; and

converging means for converging light rays from the illuminating means at the display portion of the liquid crystal panel,

said converging means including a prism lens comprising respective plurality of asymmetrical prisms having mutually different vertex angles for each of said picture elements for converging the light rays by refraction from the illuminating means at an angle within said viewing angle of the liquid crystal panel, thereby providing peak luminosity in the front axial direction.

2. A liquid crystal display comprising;

display means for displaying characters and graphics, said display means including a display portion comprising a liquid crystal panel including a plurality of picture elements and having a predetermined viewing angle characteristic in a front axial direction perpendicular to said panel;

illuminating means for illuminating the display portion of the liquid crystal panel;

reflection reducing means for reducing surface reflection of the liquid crystal panel; and

converging means for converging light rays from the illuminating means at the display portion of the liquid crystal panel,

said converging means including a prism lens comprising a respective plurality of asymmetrical prisms for each of said picture elements and having selectively different vertex angles for converging the light rays by refraction from the illuminating means at an angle substantially within the viewing angle of the liquid crystal panel for providing peak luminosity in the front axial direction.

3. A liquid crystal display comprising;

display means for displaying characters and graphics, said display means including a display portion comprising at least a liquid crystal panel including a plurality of picture elements and having a predetermined viewing angle in a front axial direction perpendicular to said panel;

illuminating means for illuminating the display portion of the liquid crystal panel; and

converging means for converging light rays from the illuminating means at the display portion of the liquid crystal panel,

said converging means including a prism lens comprising a respective plurality of truncated prisms for each of said picture elements for converging the light rays by refraction from the illuminating means at an angle within said viewing angle of the liquid crystal panel, thereby providing peak luminosity in the front axial direction.

4. A liquid crystal display according to claim 3 wherein said plurality of truncated prisms include flat uppermost surfaces.

5. A liquid crystal display comprising;

display means for displaying characters and graphics, said display means including a display portion comprising at least a liquid crystal panel including a plurality of picture elements and having a predetermined viewing angle in a front axial direction perpendicular to said panel;

illuminating means for illuminating the display portion of the liquid crystal panel; and

converging means for converging light rays from the illuminating means at the display portion of the liquid crystal panel,

said converging means including a prism lens comprising a respective plurality of prisms for each of said picture elements for converging the light rays by refraction from the illuminating means at an angle within the viewing angle of the liquid crystal panel and additionally including at least one flat portion between a pair of adjacent prisms, thereby providing peak luminosity in the front axial direction.

6. A liquid crystal display comprising;

display means for displaying characters and graphics, said display means including a display portion comprising a liquid crystal panel including a plurality of picture elements and having a predetermined viewing angle characteristic in a front axial direction perpendicular to said panel;

illuminating means for illuminating the display portion of the liquid crystal panel;

reflection reducing means for reducing surface reflection of the liquid crystal panel; and

converging means for converging light rays from the illuminating means at the display portion of the liquid crystal panel,

said converging means including a prism lens comprising a respective plurality of truncated prisms for each of said picture elements for converging the light rays by refraction from the illuminating means at an angle substantially within the viewing angle of the liquid crystal panel for providing peak luminosity in the front axial direction.

7. A liquid crystal display according to claim 6 wherein said plurality of truncated prisms include flat uppermost surfaces.

8. A liquid crystal display comprising;

display means for displaying characters and graphics, said display means including a display portion comprising a liquid crystal panel including a plurality of picture elements and having a predetermined viewing angle characteristic in a front axial direction perpendicular to said panel;

illuminating means for illuminating the display portion of the liquid crystal panel;

reflection reducing means for reducing surface reflection of the liquid crystal panel; and

converging means for converging light rays from the illuminating means at the display portion of the liquid crystal panel,

said converging means including a prism lens comprising a respective plurality of prisms for each of said picture elements and separated by flat portions for converging the light rays by refraction from the illuminating means at an angle substantially within the viewing angle of the liquid crystal panel for providing peak luminosity in the front axial direction.

9. A liquid crystal display according to claim 8 wherein said flat portions are selectively located between said prisms for setting a duty ratio of a flat portion area of a predetermined picture element of said picture elements.