Multi-functional active matrix liquid crystal displays

• US 8,233,034 B2
• Filed: 02/09/2007
• Issued: 07/31/2012
• Est. Priority Date: 02/10/2006
• Status: Active Grant

• Current Assignee: RealD Incorporated
• Original Assignee: RealD Incorporated
• Inventors: Sharp, Gary D., Robinson, Michael G.
• Primary Examiner(s): Higa, Brendan
• Application Number:
  US11/673,556
• Publication Number:
  US 20070188711A1
• Time in Patent Office: 1,999 Days
• Field of Search: 348 42- 60
• US Class Current: 348/51
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/133626 providing two modes of illumination, e.g. day-night
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 2310/024 Scrolling of light from the illumination source over the display in combination with the scanning of the display screen
• CPC Class Codes: G09G 2310/061 for resetting or blanking
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2340/06 Colour space transformation
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 3/003 to produce spatial visual effects
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
• CPC Class Codes: H04N 13/334 using spectral multiplexing

Abstract

A direct view display provides a light modulating panel and a backlight including first and second sets of spectral emitters. The first set of spectral emitters generate a first light bundle and the second set of spectral emitters generate a second light bundle. Several modes of operation may be provided including (1) an advanced 2D mode, (2) an enhanced color gamut mode employing simultaneous illumination of the first and second set of spectral emitters, (3) a privacy screen mode, (4) a channel multiplexed mode, and (5) a stereoscopic image mode. The latter three modes utilize the first and second set of spectral emitters to alternately illuminate a portion of the light modulating panel. Images and representations generated by the direct view display operating in the latter three modes are viewed using appropriate eyewear having filters with passband characteristics to transmit the respective light bundle.

Claims

1. A direct view display, comprising:

a backlight comprising a first and second set of spectral emitters operable to generate light; and

a light modulating panel operable to modulate the light;

wherein the first set of spectral emitters comprises;

a first spectral emitter selected from a pair of long band spectral emitters (R1, R2),

a second spectral emitter selected from a pair of middle band spectral emitters (G1, G2), and

a third spectral emitter selected from a pair of short band spectral emitters (B1, and B2);

wherein the second set of spectral emitters comprises;

fourth, fifth, and sixth spectral emitters comprising a complementary selection of spectral emitters to those selected for the first set of spectral emitters; and

wherein the direct view display has a multi-image mode, wherein the first and second sets of spectral emitters are operable to provide temporally alternating illumination to first and second images respectively, wherein the first set of spectral emitters is operable to provide a first light bundle to illuminate the first image, and wherein the second set of spectral emitters is operable to provide a second light bundle to illuminate the second image.

2. A direct view display according to claim 1, wherein R1 has an emission peak with a longer wavelength than R2, wherein G1 has an emission peak with a longer wavelength than G2, and wherein B1 has an emission peak with a longer wavelength than B2.

3. A direct view display according to claim 2, wherein the first set/second set of spectral emitters comprise one of the following combination R1G1B1/R2G2B2, R1G2B1/R2G1B2, R1G1B2/R2G2B1, and R1G2B2/R2G1B1.

4. A direct view display according to claim 1, wherein the spectral emitters are each operable to output a transmission range, wherein the transmission ranges from the first set of spectral emitters are substantially non-overlapping spectrally with the transmission ranges of the second set of spectral emitters.

5. A direct view display according to claim 4, wherein the R1 and R2 transmission ranges lie substantially within the sensitive wavelengths of the L-cone receptors in a human eye, wherein the G1 and G2 transmission ranges lie substantially within the sensitive wavelengths of the M-cone receptors in the human eye, and wherein the B1 and B2 transmission ranges lie substantially within the sensitive wavelengths of the S-cone receptors in the human eye.

6. A direct view display according to claim 1, wherein the direct view display outputs transmission ranges comprising emissions from first and second sets of spectral emitters through at least one color filter, wherein the first set transmission ranges are substantially non-overlapping spectrally with the second set transmission ranges.

7. A direct view display according to claim 1, wherein the direct view display has an enhanced display mode, wherein both the first and second set of spectral emitters provide simultaneous illumination.

8. A direct view display according to claim 7, wherein the first set of spectral emitters provide a first light bundle defined by a first RGB triangle of an EBU color gamut diagram, and the second set of spectral emitters provide a second light bundle defined by a second RGB triangle of the EBU color gamut diagram including colors outside the first RGB triangle, such that the enhanced display mode provides an enhanced color gamut to that produced by one light bundle.

9. A direct view display according to claim 8, wherein light output of the spectral emitters is selectively controlled to provide the enhanced color gamut.

10. A direct view display according to claim 9, wherein the selective control is via at least one of photodetector feedback circuitry, temperature feedback circuitry, and dynamic display control circuitry responsive to image content characteristics.

11. A direct view display according to claim 1, wherein the first image is viewed by a first filter comprising a first passband characteristic operable to transmit the first light bundle, and wherein the second image is viewed by a second filter comprising a second passband characteristic operable to transmit the second light bundle.

12. A direct view display according to claim 11, wherein first and second filters each comprise a retarder stack of birefringent polymer

13. A direct view display according to claim 12, wherein the direct view display further comprises an exit polarizer located on a light path following the light modulating panel, the exit polarizer having a polarization axis, wherein the first filter further comprises a first polarizer having a first axis of polarization aligned substantially parallel to the polarization axis, and wherein the second filter further comprises a second polarizer having a second axis of polarization aligned substantially orthogonally to the polarization axis.

14. A direct view display according to claim 12, wherein the first filter retarder stack has a substantially identical retardance to the second filter retarder stack.

15. A direct view display according to claim 11, further comprising eyewear for viewing a three-dimensional representation, the eyewear comprising the first filter for one eye and the second filter for the other eye, the eyewear being operable to decouple the first and second light bundles so as to form two respective half images.

16. A direct view display according to claim 11, further comprising eyewear for viewing one of the first or second output images, the eyewear comprising two filters with identical passband characteristics.

17. A direct view display according to claim 1, wherein the first and second set of spectral emitters are selected from the group consisting of:

light emitting diodes, super resonant light emitting diodes, and lasers,

18. A backlight comprising first and second sets of spectral emitters operable to generate light, wherein the first set of spectral emitters comprises:

a first spectral emitter selected from a pair of long band spectral emitters (R1, R2),

a second spectral emitter selected from a pair of middle band spectral emitters (G1, G2), and

a third spectral emitter selected from a pair of short band spectral emitters (B1, and B2);

wherein the second set of spectral emitters comprises;

fourth, fifth, and sixth spectral emitters comprising a complementary selection of spectral emitters to those selected for the first set of spectral emitters,

wherein the R1 and R2 transmission ranges lie substantially within the sensitive wavelengths of the L-cone receptors in a human eye, wherein the G1 and G2 transmission ranges lie substantially within the sensitive wavelengths of the M-cone receptors in the human eye, and wherein the B1 and B2 transmission ranges lie substantially within the sensitive wavelengths of the S-cone receptors in the human eye; and

wherein the first and second sets of spectral emitters are operable to provide temporally alternating illumination to first and second images respectively, wherein the first set of spectral emitters is operable to provide a first light bundle to illuminate the first image, and wherein the second set of spectral emitters is operable to provide a second light bundle to illuminate the second image.

19. A method for displaying images on a direct view display, the method comprising:

generating a first light bundle from a direct view display backlight using a first set of spectral emitters; and

generating a second light bundle from the direct view display backlight using a second set of spectral emitters,

wherein the first set of spectral emitters comprises;

a first spectral emitter selected from a pair of long band spectral emitters (R1, R2),

a second spectral emitter selected from a pair of middle band spectral emitters (G1, G2), and

a third spectral emitter selected from a pair of short band spectral emitters (B1, and B2);

wherein the second set of spectral emitters comprises;

fourth, fifth, and sixth spectral emitters comprising a complementary selection of spectral emitters to those selected for the first set of spectral emitters; and

wherein the direct view display has a multi-image mode, wherein the first and second sets of spectral emitters are operable to provide temporally alternating illumination to first and second images respectively, wherein the first set of spectral emitters is operable to provide a first light bundle to illuminate the first image, and wherein the second set of spectral emitters is operable to provide a second light bundle to illuminate the second image.

20. The method according to claim 19, wherein the R1 and R2 transmission ranges lie substantially within the sensitive wavelengths of the L-cone receptors in a human eye, wherein the G1 and G2 transmission ranges lie substantially within the sensitive wavelengths of the M-cone receptors in the human eye, and wherein the B1 and B2 transmission ranges lie substantially within the sensitive wavelengths of the S-cone receptors in the human eye.

21. A method for displaying a dual-image representation on a direct view display, the direct view display including a backlight having first and second sets of spectral emitters, and a light modulating panel, the method comprising:

temporally alternating illumination between the first set of spectral emitters and the second set of spectral emitters on a portion of the light modulating panel,

wherein the first set of spectral emitters do not provide illumination to the portion of the light modulating panel when the second set of spectral emitters are illuminating thereon,

wherein the second set of spectral emitters do not provide illumination to the portion of the light modulating panel when the first set of spectral emitters are illuminating thereon,

wherein the first and second sets of spectral emitters are operable to provide temporally alternating illumination to first and second images respectively, wherein the first set of spectral emitters is operable to provide a first light bundle to illuminate the first image, and wherein the second set of spectral emitters is operable to provide a second light bundle to illuminate the second image,

wherein the first set of spectral emitters comprises;

a first spectral emitter selected from a pair of long band spectral emitters (R1, R2),

a second spectral emitter selected from a pair of middle band spectral emitters (G1, G2), and

a third spectral emitter selected from a pair of short band spectral emitters (B1, and B2); and

wherein the second set of spectral emitters comprises;

fourth, fifth, and sixth spectral emitters comprising a complementary selection of spectral emitters to those selected for the first set of spectral emitters.

22. The method according to claim 21, wherein the R1 and R2 transmission ranges lie substantially within the sensitive wavelengths of the L-cone receptors in a human eye, wherein the G1 and G2 transmission ranges lie substantially within the sensitive wavelengths of the M-cone receptors in the human eye, and wherein the B1 and B2 transmission ranges lie substantially within the sensitive wavel gths of the S-cone receptors in the human eye.

23. A method for displaying an image in a direct-view display having a plurality of illumination regions, the direct-view display having a backlight with first and second sets of spectral emitters each operable to illuminate more than one of the plurality of illumination regions, the direct-view display further having a light modulating panel located between the backlight and a viewing position, the method comprising:

deactivating first and second sets of spectral emitters in a first illumination region associated with a first region of a light modulating panel;

addressing at least one pixel in the first region of the light modulating panel;

activating illumination in the first illumination region of at least one set of first and second set spectral emitters;

deactivating first and second set spectral emitters in a second illumination region associated with a second region of a light modulating panel;

addressing at least one pixel in the second region of the light modulating panel;

activating illumination in the second illumination region of at least one set of first and second set spectral emitters,

wherein the first and second sets of spectral emitters are operable to provide temporally alternating illumination to first and second images respectively, wherein the first set of spectral emitters is operable to provide a first light bundle to illuminate the first image, and wherein the second set of spectral emitters is operable to provide a second light bundle to illuminate the second image;

wherein the first set of spectral emitters comprises;

a first spectral emitter selected from a pair of long band spectral emitters (R1, R2),

a second spectral emitter selected from a pair of middle band spectral emitters (G1, G2), and

a third spectral emitter selected from a pair of short band spectral emitters (B1, and B2); and

wherein the second set of spectral emitters comprises;

fourth, fifth, and sixth spectral emitters comprising a complementary selection of spectral emitters to those selected for the first set of spectral emitters.

24. The method according to claim 23 wherein the R1 and R2 transmission ranges lie substantially within the sensitive wavelengths of the L-cone receptors in a human eye, wherein the G1 and G2 transmission ranges lie substantially within the sensitive wavelengths of the M-cone receptors in the human eye, and wherein the B1 and B2 transmission ranges lie substantially within the sensitive wavelengths of the S-cone receptors in the human eye.