Liquid crystal color display device

• US 4,678,285 A
• Filed: 01/10/1985
• Issued: 07/07/1987
• Est. Priority Date: 01/13/1984
• Status: Expired due to Fees

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Uehara, Kiyohiro, Enomoto, Takamichi, Ohta, Wasaburo
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): Lewis, David
• Application Number:
  US06/690,267
• Time in Patent Office: 908 Days
• Field of Search: 313/112, 313/487, 313/485, 313/484, 350/345, 350/337, 350/339 F
• US Class Current: 349/71
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133614 using photoluminescence, e.g. phosphors illuminated by UV or blue light
• CPC Class Codes: G02F 1/133617 Illumination with ultraviolet light; Luminescent elements or materials associated to the cell
• CPC Class Codes: H04N 3/127 using liquid crystals

Abstract

A liquid crystal color display device for displaying a color image represented by an applied image signal, including a liquid crystal cell, one or two polarizers, and a fluorescent light-emitting means. The liquid crystal cell and one polarizer disposed on one side thereof, or the liquid crystal cell and the two polarizers sandwiching the same, jointly constitute a switching element responsive to the image signal applied to the liquid crystal cell for passing electromagnetic radiation in a pattern representing the image given by the image signal. The fluorescent light-emitting means has a fluorescent layer and a lamp for generating electromagnetic radition, and may additionally include a color filter. The fluorescent layer is responsive to the electromagnetic radiation from the lamp for emitting chromatic fluorescent light. Where the fluorescent light-emitting means has the color filter, the fluorescent light passes through the color filter to display the image.

Claims

1. A liquid crystal color display device for displaying a color image in response to a given image signal, comprising:

a liquid crystal cell composed of a liquid crystal material, a pair of transparent plates sandwiching said liquid crystal material therebetween, a transparent electrode mounted on one of said transparent plates and composed of plural electrode elements, and a flat transparent electrode mounted on the other transparent plate in confronting relation to said plural electrode elements;

at least one polarizer;

a color filter composed of a plurality of filters for passing red, green, and blue fluorescent lights therethrough, said filters being disposed in alignment with respective of said electrode elements;

fluorescent light-emitting means comprising a fluorescent layer and a lamp for generating electromagnetic radiation, said fluorescent layer being composed of a plurality of fluorescent layer elements capable of emitting red, green, and blue fluorescent lights in response to application thereto of electromagnetic radiation from said lamp, said fluorescent layer elements being aligned with respective of the plurality of filters of said color filter; and

said liquid crystal cell, said at least one polarizer, and said lamp being successively arranged in the order named away from an observation side, said color filter being disposed more closely to the observation side than said fluorescent layer.

2. A liquid crystal color device according to claim 1, further comprising:

said fluorescent layer disposed between said at least one polarizer and said lamp.

3. A liquid crystal color display according to claim 2, further comprising:

an additional polarizer facing said liquid crystal cell on a side of said cell opposite said lamp.

4. A liquid crystal color display according to claim 2, wherein said fluorescent layer is formed on a surface of said at least one polarizer facing said lamp.

5. A liquid crystal color display according to claim 4, further comprising:

an additional polarizer facing said liquid crystal cell on a side of said cell opposite said lamp.

6. A liquid crystal color display device according to claim 4, further comprising:

said color filter disposed on one of the pair of transparent plates of said liquid crystal cell, said one of said pair of transparent plates facing said at least one polarizer.

7. A liquid crystal color display according to claim 6, further comprising:

an additional polarizer facing said liquid crystal cell on a side of said cell opposite said lamp.

8. A liquid crystal color display device according to claim 4, wherein said color filter is formed on a surface of said at least one polarizer facing said liquid crystal cell.

9. A liquid crystal color display according to claim 8, further comprising:

an additional polarizer facing said liquid crystal cell on a side of said cell opposite said lamp.

10. A liquid crystal color display device according to claim 1, further comprising:

said color filter formed on a surface of one of the pair of transparent plates of said liquid crystal cell facing said first polarizer, and

said liquid crystal color display device further comprising an additional transparent plate disposed between said at least one polarizer and said lamp, said fluorescent layer formed on a surface of said additional transparent plate facing said lamp.

11. A liquid crystal color display according to claim 10, further comprising:

an additional polarizer facing said liquid crystal cell on a side of said cell opposite said lamp.

12. A liquid crystal color display device according to claim 1, comprising:

an additional transparent plate disposed between said first polarizer and said lamp, said additional transparent plate having opposed surfaces including a first surface facing said lamp and a second surface facing said polarizer, said fluorescent layer formed on said first surface and said color filter formed on said second surface.

13. A liquid crystal color display according to claim 12, further comprising:

an additional polarizer facing said liquid crystal cell on a side of said cell opposite said lamp.

14. A liquid crystal color display according to claim 1, further comprising:

an additional polarizer facing said liquid crystal cell on a side of said cell opposite said lamp.

15. A liquid crystal color display device according to claim 1, wherein said plurality of electrode elements comprises perpendicular stripe electrodes.

16. A liquid crystal color display device according to claim 1, wherein said plurality of electrode elements comprises a matrix of minute electrode elements.

17. A liquid crystal color display device according to claim 16, wherein said color filter comprises a mosaic pattern of minute pixel filters.

18. A liquid crystal color display device according to claim 17, wherein said fluorescent layer comprises a mosaic of minute fluorescent layer elements aligned with respective of the pixel filters of said color filter.

19. A liquid crystal display device according to claim 1, wherein said plurality of electrode elements comprises a plurality of electrode segments.