Stereoscopic 3D liquid crystal display with segmented light guide

• US 7,800,708 B2
• Filed: 10/02/2007
• Issued: 09/21/2010
• Est. Priority Date: 10/06/2006
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Ehnes, Dale L., Meis, Michael A., Lundin, David J., Brott, Robert L., Nelson, John C.
• Primary Examiner(s): Nguyen; Hoan C
• Application Number:
  US11/866,017
• Publication Number:
  US 20080084513A1
• Time in Patent Office: 1,085 Days
• Field of Search: 349/61, 349/62, 349/64, 349/65, 362/26, 362/27, 362 29- 30, 362/225, 362/600, 362/602, 362/611, 362/612, 362615-616
• US Class Current: 349/61
• CPC Class Codes: G02B 30/24 involving temporal multiplexing, e.g. using sequentially activated left and right shutters
• CPC Class Codes: G02B 30/27 involving lenticular arrays
• CPC Class Codes: G02B 30/33 involving directional light or back-light sources
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• CPC Class Codes: G02B 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G02B 6/0076 Stacked arrangements of multiple light guides of the same or different cross-sectional area
• CPC Class Codes: G02B 6/0078 Side-by-side arrangements, e.g. for large area displays
• CPC Class Codes: H04N 13/32 using arrays of controllable light sources; using moving apertures or moving light sources
• CPC Class Codes: H04N 13/398 Synchronisation thereof; Control thereof
• CPC Class Codes: Y10S 385/901 Illuminating or display apparatus

Abstract

A backlight for a stereoscopic 3D liquid crystal display apparatus includes a light guide formed from a plurality of segments. Each segment has a first side and a second side opposite the first side, and a first surface extending between the first and second sides and a second surface opposite the first surface. The first surface substantially re-directs light and the second surface substantially transmits light. The plurality of segments are arranged substantially in parallel with the second surfaces transmitting light in substantially the same direction to provide backlighting for a stereoscopic 3D liquid crystal display. A light source is disposed along only one of the first side or second side of each segment for transmitting light into the light guide from either the first side or second side. Each segment light source is selectively turned on and off in a particular pattern.

Claims

1. A backlight for a stereoscopic 3D liquid crystal display apparatus, comprising:

a light guide formed from a plurality of segments, each segment having a first side and a second side opposite the first side, and having a first surface extending between the first and second sides and a second surface opposite the first surface, wherein the first surface substantially re-directs light and the second surface substantially transmits light, and the plurality of segments are arranged substantially in parallel with the second surfaces transmitting light in substantially the same direction to provide backlighting for a stereoscopic 3D liquid crystal display;

a light source is disposed along only one of the first side or second side of each segment for transmitting light into the light guide from either the first side or second side;

wherein, each segment light source is selectively turned on and off in a particular pattern.

2. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, wherein the light sources are located on opposing first and second sides of each pair of adjacent segments.

3. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, wherein the segments include a graded extractor that provides substantially uniform extraction of light from the second surface.

4. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, wherein each light source comprises a one or more light emitting diodes.

5. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, wherein the segments have a converging wedge shape with the light source located at a wide side of the converging wedge.

6. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, wherein each segment is partially separated from an adjacent segment by an air gap and each segment is joined with an adjacent segment at the first surface, or second surface, or between the first surface and second surface.

7. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, wherein each segment is completely separated from an adjacent segment by an air gap.

8. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, wherein each segment is completely separated from an adjacent segment.

9. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, further comprising a synchronization driving element electrically coupled to the light sources and the synchronization driving element synchronizes turning each light source on or off in an alternating order between the first and second sides.

10. A backlight for a stereoscopic 3D liquid crystal display apparatus according to claim 1, wherein the plurality of segments comprise elongated rods.

11. A stereoscopic 3D liquid crystal display apparatus, comprising:

a liquid crystal display panel;

drive electronics configured to drive the liquid crystal display panel with alternating left eye and right eye images; and

a backlight positioned to provide light to the liquid crystal display panel, the backlight comprising;

a light guide formed from a plurality of segments, each segment having a first side and a second side opposite the first side, and having a first surface extending between the first and second sides and a second surface opposite the first surface, wherein the first surface substantially re-directs light and the second surface substantially transmits light, and the plurality of segments are arranged substantially in parallel with the second surfaces transmitting light in substantially the same direction to provide backlighting for a stereoscopic 3D liquid crystal display;

a light source is disposed along only one of the first side or second side of each segment for transmitting light into the light guide from either the first side or second side;

wherein, each segment light source is selectively turned on and off in a particular pattern.

12. A stereoscopic 3D liquid crystal display apparatus according to claim 11, wherein the segments have a converging wedge shape with the light source located at a wide side of the converging wedge.

13. A stereoscopic 3D liquid crystal display apparatus according to claim 11, wherein each light source selectively transmits light into the light guide based upon whether a right or left image is displayed on the liquid crystal display panel.

14. A stereoscopic 3D liquid crystal display apparatus according to claim 11, wherein each light source is turned on or off in an alternating order between the first and second sides and the light sources are located on opposing first and second sides of each pair of adjacent segments.

15. A stereoscopic 3D liquid crystal display apparatus according to claim 11, further comprising a synchronization driving element electrically coupled to the light sources and the synchronization driving element synchronizes turning each segment on or off in an alternating order between the first and second sides.

16. A stereoscopic 3D liquid crystal display apparatus according to claim 11, wherein each segment is partially separated from an adjacent segment by an air gap and the each segment is joined with an adjacent segment at the first planar surface, or second planar surface, or between the first planar surface and second planar surface.

17. A stereoscopic 3D liquid crystal display apparatus according to claim 11, wherein each segment is completely separated from an adjacent segment.

18. A stereoscopic 3D liquid crystal display apparatus according to claim 11, wherein the plurality of segments comprise elongated rods.

19. A stereoscopic 3D liquid crystal display apparatus according to claim 11, wherein each light source comprises a one or more light emitting diodes.

20. A stereoscopic 3D liquid crystal display apparatus according to claim 11, wherein each segment first or second side has a length and a width, or diameter value of 2 millimeters or less.