SCANNING COLLIMATION OF LIGHT VIA FLAT PANEL LAMP

• US 20110043142A1
• Filed: 11/18/2009
• Published: 02/24/2011
• Est. Priority Date: 08/21/2009
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Emerton, Neil, Large, Timothy, Travis, Adrian, Bathiche, Steven
• Granted Patent: US 8,354,806 B2
• Time in Patent Office: Days
• US Class Current: 315/313
• CPC Class Codes: G02B 26/108 having one or more prisms as scanning elements
• CPC Class Codes: G02B 27/30 Collimators
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer

Abstract

Various embodiments are disclosed that relate to scanning the direction of light emitted from optical collimators. For example, one disclosed embodiment provides a system for scanning collimated light, the system comprising an optical wedge, a light injection system, and a controller. The optical wedge comprises a thin end, a thick end opposite the thin end, a viewing surface extending at least partially between the thick end and the thin end, and a back surface opposite the viewing surface. The thick end of the optical wedge further comprises an end reflector comprising a faceted lens structure. The light injection system is configured to inject light into the thin end of the optical wedge, and the controller is configured to control the location along the thin end of the optical wedge at which the light injection system injects light.

Claims

1. A system for scanning collimated light, the system comprising:

an optical waveguide comprising;

a first end,

a second end opposite the first end,

a viewing surface extending at least partially between the first end and the second end,

a back surface opposite the viewing surface, and

an end reflector disposed at the second end of the optical waveguide, the end reflector comprising one or more of a faceted lens structure and a diffraction grating;

a light injection system configured to inject light into the first end of the optical waveguide; and

a controller configured to control a location along the first end of the optical waveguide at which the light injection system injects light.

2. The system of claim 1, wherein the light injection system comprises a plurality of light sources arranged along the first end of the optical waveguide, each light source configured to inject light into the first end of the optical waveguide at a different location along the first end of the optical waveguide.

3. The system of claim 2, wherein the controller is configured to concurrently illuminate two or more light sources of the plurality of light sources to display an image along more than one direction.

4. The system of claim 2, wherein the controller is configured to illuminate one light source of the plurality of light sources to display an image along one direction.

5. The system of claim 2, wherein the controller is configured to consecutively illuminate the plurality of light sources to display an autostereoscopic image.

6. The system of claim 2, further comprising a head-tracking camera and wherein the controller is further configured to receive data from the head-tracking camera and to create head-tracking data.

7. The system of claim 6, wherein the system further comprises two or more selectable modes comprising a private mode and a public mode, the private mode for directing collimated light toward a single viewer, the public mode for directing collimated light toward more than one viewer;

and

wherein the controller is further configured to illuminate one or more light source of the plurality of light sources according to the mode of the system and the head-tracking data.

8. The system of claim 2, wherein the controller is further configured to consecutively illuminate the plurality of light sources to display one or more images to one or more viewers.

9. The system of claim 1, wherein the light injection system comprises a diffusive screen arranged along the first end of the optical waveguide and a light source configured to generate a laser beam that is scanned along the diffusive screen.

10. The system of claim 1, further comprising a light redirector disposed adjacent to the viewing surface and configured to receive light from the viewing surface and redirect the light received from the viewing surface.

11. A system for scanning collimated light, the system comprising:

an optical wedge comprising;

a thin end,

a thick end disposed opposite the thin end,

a viewing surface extending at least partially between the thin end and the thick end, the viewing surface comprising a first critical angle of reflection relative to a direction normal to the viewing surface,

a back surface disposed opposite the viewing surface and comprising a second critical angle of reflection relative to a direction normal to the back surface, wherein the second critical angle is less than the first critical angle, and

an end reflector disposed at the thick end of the optical wedge, the end reflector having a faceted lens structure configured to reflect internally transmitted incident light that travels along an optical path between the thin end and the viewing surface;

a plurality of light sources arranged along the thin end of the optical wedge, each light source being configured to inject light into the thin end of the optical wedge; and

a controller configured to independently and selectively illuminate each light source of the plurality of light sources according to a mode of the system.

12. The system of claim 11, wherein the mode of the system comprises one or more of a private mode, a public mode, an autostereoscopic mode, and a scanning mode.

13. The system of claim 11, further comprising a camera, and wherein the controller is further configured to receive image data from the camera and to create head-tracking data from the image data.

14. The system of claim 13, wherein the controller is further configured to illuminate one light source of the plurality of light sources according to head-tracking data when in a private mode, whereby collimated light is directed toward a head of a single viewer.

15. The system of claim 13, wherein the controller is further configured to alternately illuminate a first light source and a second light source of the plurality of light sources according to head-tracking data when in an autostereoscopic mode, whereby collimated light from the first light source is directed toward a first eye of a viewer and collimated light from the second light source is directed toward a second eye of the viewer.

16. The system of claim 11, wherein the controller is further configured to illuminate one or more light source of the plurality of light sources when in a public mode.

17. The system of claim 11, further comprising:

a light redirector disposed adjacent to the viewing surface and configured to receive light from the viewing surface and redirect the light received from the viewing surface.

18. A method of scanning collimating light via an optical waveguide, the optical waveguide comprising a first end, a second end opposite the first end and comprising an end reflector, a viewing surface extending between the first end and the second end, and a back surface opposing the viewing surface, the method comprising:

injecting light into the first end of the optical waveguide;

delivering the light to the end reflector via total internal reflection;

internally reflecting the light off of the end reflector;

emitting a first portion of light from the viewing surface at a critical angle of reflection;

internally reflecting a second portion of light from the back surface at an angle equal to the critical angle of reflection, and then emitting the second portion of light from the viewing surface after internally reflecting the second portion of light from the back surface; and

varying a location along the first end of the optical waveguide at which light is injected into the optical waveguide.

19. The method of claim 18, wherein injecting light into the first end comprises injecting light from a light source configured to generate a laser beam that is scanned along a diffusive screen arranged along the first end of the optical waveguide, and wherein varying a location along the first end of the optical waveguide at which the light is injected into the optical waveguide comprises scanning the laser beam along the diffusive screen.

20. The method of claim 18, wherein injecting light into the first end comprises injecting light from a plurality of light sources, and wherein varying a location along the first end of the optical waveguide at which the light is injected into the optical waveguide comprises selectively illuminating a light source from the plurality of light sources.