HEADS-UP DISPLAY INCLUDING AMBIENT LIGHT CONTROL

• US 20130108229A1
• Filed: 10/28/2011
• Published: 05/02/2013
• Est. Priority Date: 10/28/2011
• Status: Abandoned Application

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Wang, Chia-Jean, Miao, Xiaoyu, Spitzer, Mark B., Starner, Thad E., Keyes, Edward
• Application Number:
  US13/284,743
• Publication Number:
  US 20130108229A1
• Time in Patent Office: Days
• US Class Current: 385/119
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 27/01 Head-up displays
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00

Abstract

Implementations are described of a waveguide apparatus including a proximal end, a distal end, a front surface and a back surface, the back surface being spaced apart from the front surface. A display input region is positioned at or near the proximal end, an ambient input region is positioned on the front surface near the distal end and an output region is positioned on the back surface near the distal end. One or more optical elements is positioned in or adjacent to the waveguide to direct display light from the display input region to the output region and to direct ambient light from the ambient input region to the output region, and an switchable mirror layer is positioned in or on the waveguide to selectively control the amount of ambient light that is directed to the output region. Other embodiments are disclosed and claimed.

Claims

1. A waveguide apparatus comprising:

a proximal end, a distal end, a front surface and a back surface, the back surface being spaced apart from the front surface;

a display input region at or near the proximal end;

an ambient input region on the front surface near the distal end and an output region on the back surface near the distal end;

one or more optical elements positioned in or adjacent to the waveguide to direct display light from the display input region to the output region and to direct ambient light from the ambient input region to the output region; and

a switchable mirror layer positioned in or on the waveguide to selectively control the amount of ambient light that is directed to the output region.

2. The apparatus of claim 1 wherein the one or more optical elements include an internal surface with optical power.

3. The apparatus of claim 2 wherein the switchable mirror layer is positioned on the internal surface.

4. The apparatus of claim 1 wherein the switchable mirror layer can regulate the amount of ambient light to be directed to the output region.

5. The apparatus of claim 4 wherein the switchable mirror layer is controlled using a variable electrical bias.

6. The apparatus of claim 4 wherein the switchable mirror layer can allow substantially all ambient light to be directed to the output region and can allow substantially no ambient light to be directed to the output region.

7. The apparatus of claim 1 wherein the one or more optical elements include a polarizing beam splitter.

8. The apparatus of claim 7 wherein the switchable mirror layer is formed on the front surface over at least a portion of the ambient input region.

9. The apparatus of claim 8, one or more optical elements further include:

a focusing element positioned at the distal end of the waveguide; and

a quarter-wave plate positioned between the focusing element and the distal end of the waveguide.

10. The apparatus of claim 1 wherein the one or more optical elements include a partially-reflective mirror.

11. The apparatus of claim 9 wherein the switchable mirror layer is formed on the partially-reflective mirror.

12. The apparatus of claim 1 wherein the switchable mirror layer is patterned with individually controllable regions to selectively direct the ambient light to portions of the output region.

13. The apparatus of claim 12 wherein the switchable mirror layer is patterned with a plurality of abutting switchable mirror tiles.

14. The apparatus of claim 12 wherein the switchable mirror layer is patterned with a central switchable mirror circle surrounded by a plurality of abutting concentric switchable mirror annuluses of increasing radius.

15. The apparatus of claim 1, further comprising:

a first photosensor to measure the intensity of the display light;

a second photosensor to measure the intensity of the ambient light;

a control circuit coupled to the first photo sensor and the second photosensor, to a display optically coupled to the waveguide, and to a variable and controllable electrical bias source.

16. A system comprising:

a waveguide comprising;

a proximal end, a distal end, a front surface and a back surface, the back surface being spaced apart from the front surface,

a display input region at or near the proximal end,

an ambient input region on the front surface near the distal end and an output region on the back surface near the distal end,

one or more optical elements positioned in or adjacent to the waveguide to direct display light from the display input region to the output region and to direct ambient light from the ambient input region to the output region, and

a switchable mirror layer positioned in or on the waveguide to selectively control the amount of ambient light that is directed to the output region;

a display optically coupled to the display input region; and

a controllable electrical bias source coupled to the switchable mirror layer.

17. The system of claim 16 wherein the one or more optical elements include an internal surface with optical power.

18. The system of claim 17 wherein the switchable mirror layer is positioned on the internal surface.

19. The system of claim 16 wherein the switchable mirror layer can be controlled using the electrical bias source to regulate the amount of ambient light to be directed to the output region.

20. The system of claim 19 wherein the switchable mirror layer can allow substantially all ambient light to be directed to the output region and can allow substantially no ambient light to be directed to the output region.

21. The system of claim 16 wherein the one or more optical elements include a polarizing beam splitter.

22. The system of claim 21 wherein the switchable mirror layer is formed on the front surface and covers at least a portion of the ambient input region.

23. The system of claim 22, further comprising:

a focusing element positioned at the distal end of the waveguide; and

a quarter-wave plate positioned between the focusing element and the distal end of the waveguide.

24. The system of claim 16 wherein the one or more optical elements include a partially-reflective mirror.

25. The system of claim 24 wherein the switchable mirror layer is formed on the partially-reflective mirror.

26. The system of claim 16 wherein the switchable mirror layer is patterned with individually controllable regions coupled to the electrical bias source to selectively direct the ambient light to portions of the output region.

27. The system of claim 26 wherein the switchable mirror layer is patterned with a plurality of abutting switchable mirror tiles.

28. The system of claim 26 wherein the switchable mirror layer is patterned with a central switchable mirror circle surrounded by a plurality of abutting concentric switchable mirror annuluses of increasing radius.

29. The system of claim 16, further comprising:

a first photosensor to measure the intensity of the display light;

a second photosensor to measure the intensity of the ambient light; and

a control circuit coupled to the first photo sensor and the second photosensor, to the display, and to the controllable electrical bias source.

30. A process comprising:

positioning a waveguide in front of at least one eye of a user, the waveguide comprising;

a proximal end, a distal end, a front surface and a back surface, the back surface being spaced apart from the front surface,

a display input region at the proximal end,

an ambient input region and an output region at the distal end,

one or more optical elements positioned in or adjacent to the waveguide to direct display light from the display input region to the output region and to direct ambient light from the ambient input region to the output region, and

a switchable mirror layer positioned in or on the waveguide to selectively control the amount of ambient light that is directed to the output region;

directing display light from a display into the display input region;

directing ambient light from a scene into the ambient input region; and

regulating the relative proportions of ambient light and display light seen by the user by controlling an electrical bias applied to the switchable mirror layer

31. The process of claim 30, further comprising regulating the relative proportions of ambient light and display light seen by the user by controlling brightness of the display.

32. The process of claim 30, further comprising:

measuring the intensity of the display light;

measuring the intensity of the ambient light; and

using the measured intensities to automatically regulate the relative proportions of ambient light and display light seen by the user by controlling the electrical bias, the brightness of the display, or both.