IP Library Granted Patent US 7,639,320
Granted Patent B2
US 7,639,320 · App. 11/869,900 · Granted Dec 29, 2009

Liquid crystal display device

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Quick Facts
Patent No.
US 7,639,320
App. No.
11/869,900
Granted
Dec 29, 2009
Kind
B2
Abstract

In a liquid crystal display device, rays of light of a light source for blue light emission are concentrated on a fluorescent material by using a lens of a first micro-lens array and fluorescent rays from the fluorescent material are concentrated on a pixel of corresponding color by using a lens of a second micro-lens array.

Claims (29)

1. A liquid crystal display device comprising:

a liquid crystal panel including a first substrate, a second substrate and a liquid crystal layer sandwiched between said first and second substrates;

a light source for emitting rays of blue light; and

a light conversion layer arranged between said liquid crystal panel and said light source and including a first micro-lens array having a plurality of lenses arranged, a second micro-lens array having a plurality of lenses arranged and a fluorescent layer arranged between said first and second micro-lens arrays.

2. A liquid crystal device according to claim 1 , wherein said first micro-lens array of said light conversion layer has the function to concentrate the rays of blue light from said light source on said fluorescent layer, and said second lens array of said light conversion layer has the function to concentrate fluorescent rays emitted from said fluorescent layer or the blue light rays from said light source on a corresponding pixel inside said liquid crystal panel.

3. A liquid crystal display device according to claim 2 further comprising a light guide arranged between said light source and said light conversion layer and causing the blue light rays from said light source to be directed to said light conversion layer.

4. A liquid crystal display device according to claim 2 , wherein each of said plurality of lenses of said first micro-lens array has a sectional form which is convex toward the side on which said light source is arranged, and each of said plurality of lenses of said second micro-lens array has a sectional form which is convex toward the side on which said liquid crystal panel is arranged.

5. A liquid crystal display device according to claim 2 , wherein said liquid crystal panel includes a plurality of pixels and a plurality of color filters, said fluorescent layer has fluorescent materials for red color and fluorescent materials for green color and said red fluorescent material and green fluorescent material are arranged in correspondence with colors of said color filters associated with respective ones of said plural pixels.

6. A liquid crystal display device according to claim 2 , wherein lenses of said first micro-lens array and lenses of said second micro-lens array are distributed identically in a planar configuration.

7. A liquid crystal display device according to claim 3 , wherein said light source has a blue light emitting diode, said blue light emitting diode is arranged at one end of said light guide, said light guide is mounted with a hologram or a blazed grating, and said hologram or blazed grating converts luminescence of said blue light emitting diode into a plane light source to cause the luminescence to be directed toward the normal direction of said liquid crystal panel.

8. A liquid crystal display device according to claim 2 , wherein the fluorescent material of said fluorescent layer is arranged at a focal point position of the lens of said first micro-lens array.

9. A liquid crystal display device according to claim 2 , wherein the fluorescent material of said fluorescent layer is arranged remotely from the lens of said second micro-lens array in excess of its focal point position.

10. A liquid crystal display device according to claim 2 further comprising a leveling portion provided between adjacent ones of said plurality of lenses each of said first and second micro-lens arrays has and a leveling portion absorptive or reflective layer is arranged between the adjacent lenses of each of said first and second micro-lens arrays in association with a corresponding leveling portion.

11. A liquid crystal display device according to claim 1 , wherein marks for positioning said light conversion layer and said liquid crystal panel are formed on said light conversion layer and said liquid crystal panel.

12. A liquid crystal display device according to claim 2 , wherein said light conversion layer includes a third substrate, said first and second micro-lens arrays are formed on opposite surfaces of said third substrate, and said fluorescent layer is formed on said third substrate.

13. A liquid crystal display device according to claim 2 , wherein said liquid crystal panel has a plurality of pixels and each of said plurality of pixels is associated with a comb-teeth or slit shaped pixel electrode and a common electrode formed all over the pixels.

14. A liquid crystal display device according to claim 2 , wherein said liquid crystal panel has a plurality of pixels and each of said plurality of pixels has a transmissive display portion and a reflective display portion.

15. A liquid crystal display device comprising:

a liquid crystal panel including a first substrate, a second substrate and a liquid crystal layer sandwiched between said first and second substrates;

a pair of polarization plates for putting said liquid crystal panel therebetween;

a light source for emitting rays of blue light;

a light guide arranged between said liquid crystal panel and said light source;

a light conversion layer arranged between said liquid crystal panel and said light guide and including a first micro-lens array having a plurality of lenses arranged, a second micro-lens array having a plurality of lenses arranged and a fluorescent layer arranged between said first micro-lens arrays and said light guide; and

a fluorescence reflective layer arranged between said light guide and said fluorescent layer,

wherein one of said paired polarization plates is arranged between said first and second micro-lens arrays.

16. A liquid crystal display device according to claim 15 , wherein said first micro-lens array of said light conversion layer has the function to concentrate on said fluorescent layer the blue light rays emitting from said light source and coming to said light guide, and said second lens array of said light conversion layer has the function to concentrate on a corresponding pixel inside said liquid crystal panel fluorescent rays from said fluorescent layer or the blue light rays from said light source both going out through said one of polarization plates.

17. A liquid crystal display device according to claim 15 , wherein each of said plurality of lenses of said first micro-lens array has a sectional form which is convex toward the side on which said liquid crystal panel is arranged, and each of said plurality of lenses of said second micro-lens array has a sectional form which is convex toward the side on which said light source is arranged.

18. A liquid crystal display device according to claim 15 , wherein said light guide has a blazed grating.

19. A liquid crystal display device according to claim 15 , wherein said liquid crystal panel has a plurality of pixels and each of said plurality of pixels is associated with a comb-teeth or slit shaped pixel electrode and a common electrode formed all over the pixels.

Assignments (3)
COMPANY SPLIT PLAN TRANSFERRING FIFTY (50) PERCENT SHARE OF PATENTS Recorded Oct 14, 2011
From: HITACHI DISPLAYS, LTD.
To: IPS ALPHA SUPPORT CO., LTD.
Reel/Frame 027063/0019 →
MERGER Recorded Oct 14, 2011
From: IPS ALPHA SUPPORT CO., LTD.
To: PANASONIC LIQUID CRYSTAL DISPLAY CO., LTD.
Reel/Frame 027063/0139 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 8, 2007
From: ITOU, OSAMU; SUGITA, TATSUYA; ADACHI, MASAYA; KOMURA, SHINICHI; HIROTA, SHOICHI
To: HITACHI DISPLAYS, LTD.
Reel/Frame 020086/0192 →