Optical illuminator for liquid crystal displays

• US 5,682,213 A
• Filed: 07/01/1994
• Issued: 10/28/1997
• Est. Priority Date: 07/01/1994
• Status: Expired due to Fees

• Current Assignee: AOA Xinetics (Northrop Grumman Corporation)
• Original Assignee: AOA Xinetics (Northrop Grumman Corporation)
• Inventors: Schmutz, Lawrence E.
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): Duong, Tai V.
• Application Number:
  US08/269,725
• Time in Patent Office: 1,215 Days
• Field of Search: 359/40, 359/41, 359/48, 359/42, 385/16, 385/17, 385/88, 385/89, 385/115, 385/116, 385/119, 385/901, 362/32, 362/26, 362/27, 349/61, 349/62, 349/71, 349/106, 349/95, 349/57
• US Class Current: 349/61
• CPC Class Codes: G02B 6/001 the light being emitted along at least a portion of the lateral surface of the fibre
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G02F 1/133617 Illumination with ultraviolet light; Luminescent elements or materials associated to the cell
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: Y10S 385/901 Illuminating or display apparatus

Abstract

The present invention teaches a liquid crystal display system comprising a liquid crystal display ("LCD") having a plurality of pixels. Moreover the system comprises an illuminator for illuminating each of said plurality of pixels. The illuminator comprises an optical fiber for transmitting a light beam within said fiber, and a number of discrete scattering sites positioned along the fiber for scattering a portion of the light beam outside said fiber. The number of discrete scattering sites are optically coupled with the plurality of pixels such that the plurality of pixels are illuminated by the light beam scattered outside the fiber through the number of discrete scattering sites.

Claims

1. A liquid crystal display system comprising:

a liquid crystal display having a plurality of pixels; and

an illuminator for illuminating each of said plurality of pixels comprising;

an optical fiber for transmitting a light beam within said fiber, and a number of discrete scattering sites positioned along the length of said fiber for scattering a portion of the light beam outside said fiber, each site of said number of discrete scattering sites being optically coupled with more than one pixel of said plurality of pixels such that of said plurality of pixels are illuminated by the light beam scattered outside said fiber through said number of discrete scattering sites.

2. The system of claim 1, further comprising:

a lens arrangement for optically coupling said number of discrete scattering sites with said plurality of pixels.

3. The system of claim 2, wherein said lens arrangement comprises at least one of a micro-optic multiplet lenslet and an integrated monolithic lenslet module.

4. The system of claim 3, wherein said lens arrangement is formed on a substrate.

5. A chromatic liquid crystal display system comprising:

a liquid crystal display having a plurality of pixel sets, each pixel set comprising a plurality of pixels; and

a colorized illuminator for illuminating each of said plurality of pixel sets with a colorized light beam, said colorized illuminator comprising;

an optical fiber for transmitting a light beam within said fiber, said fiber having a number of discrete scattering sites positioned along the length of said fiber for scattering a portion of the light beam outside said fiber;

a first lens arrangement for optically coupling each site of said number of discrete scattering sites with more than one pixel of said plurality of pixels; and

a color filter for colorizing the portion of the light beam scattered outside said fiber.

6. The system of claim 5, further comprising a second lens arrangement for recombining emissions from each of said pixel sets into a resultant color.

7. The system of claim 6, wherein at least one of said first lens arrangement and said second lens arrangement comprises a micro-optic multiplet lenslet.

8. The system of claim 6, wherein at least one of said first lens arrangement and said second lens arrangement is formed on a substrate.

9. The system of claim 5, wherein said color filter comprises at least one of a red filter, a green filter, and a blue filter.

10. The system of claim 5, wherein each of said pixel sets comprise a red pixel having a first output, a green pixel having a second output and a blue pixel having a third output, and said system further comprises means for fusing said outputs of each of said pixels of each of said pixel sets, such that a resultant luminance pixel is realized having a desired color for each of said pixel sets.

11. The system of claim 10, wherein said means for fusing said outputs comprises:

a first lenslet array for spatially converging each of said outputs filtered by a transmission grating; and

a second lenslet array for magnifying said outputs spatially converged by said first lenslet array such that any voids between said pixels are substantially filled.

12. The system of claim 10, wherein said means for fusing said outputs comprises:

a non-imaging concentrator for converging said outputs to an exit aperture such that said outputs are substantially mixed; and

a first lenslet array for magnifying said outputs mixed by said non-imaging concentrator such that any voids between said pixels are substantially filled.

13. A chromatic liquid crystal display system comprising:

a liquid crystal display having a plurality of pixel sets, said pixel sets comprising;

a red pixel having a first output, a green pixel having a second output and a blue pixel having a third output, and said system further comprises a means for fusing said outputs of each of said pixels of each of said pixel sets, such that a resultant luminance pixel is realized having a desired color for each of said pixel sets, said means for fusing said outputs comprising;

a first lenslet array for spatially converging each of said outputs filtered by a transmission grating;

a second lenslet array for magnifying said outputs filtered by said grating such that any voids between said pixels are substantially filled;

an illuminator for illuminating each of said plurality of pixel sets, said illuminator comprising;

a group of optical fibers, each fiber of said group transmitting a light beam within said fiber, each fiber of said group having a number of discrete scattering sites positioned along said fiber for scattering a portion of the light beam outside said fiber, said group of fibers comprising a red, green and a blue fiber; and

a first lens arrangement for optically coupling said number of discrete scattering sites of each fiber of said group of fibers with said plurality of pixels.

18. The system of claim 13 or 14, wherein said number of discrete scattering points of at least one of said red, blue and green fibers comprise a fluorescent composition.

14. A chromatic liquid crystal display system comprising:

a liquid crystal display having a plurality of pixel sets, said pixel sets comprising;

a red pixel having a first output, a green pixel having a second output and a blue pixel having a third output, and said system further comprises a means for fusing said outputs of each of said pixels of each of said pixel sets, such that a resultant luminance pixel is realized having a desired color for each of said pixel sets, said means for fusing said outputs comprising;

a non-imaging concentrator for converging said outputs to an exit aperture such that said outputs are substantially mixed;

a first lenslet array for magnifying said outputs mixed by said non-imaging concentrator such that any voids between said pixels are substantially filled;

an illuminator for illuminating each of said plurality of pixel sets, said illuminator comprising;

a group of optical fibers, each fiber of said group transmitting a light beam within said fiber, each fiber of said group having a number of discrete scattering sites positioned along said fiber for scattering a portion of the light beam outside said fiber, said group of fibers comprising a red, green and a blue fiber; and

a first lens arrangement for optically coupling said number of discrete scattering sites of each fiber of said group of fibers with said plurality of pixels.

15. The system of claim 14, further comprising a second lens arrangement for recombining emissions from each of said groups of discrete scattering sites into a resultant color.

16. The system of claim 15, wherein at least one of said first lens arrangement and said second lens arrangement comprises at least one of a micro-optic multiplet lenslet and an integrated monolithic lenslet module.

17. The system of claim 15, wherein at least one of said first lens arrangement and said second lens arrangement is formed on a substrate.