HEAD-MOUNTED DISPLAY WITH AN EYEBALL-TRACKER INTEGRATED SYSTEM

• US 20150138451A1
• Filed: 05/19/2013
• Published: 05/21/2015
• Est. Priority Date: 05/21/2012
• Status: Active Grant

• Current Assignee: Lumus Ltd.
• Original Assignee: Lumus Ltd.
• Inventors: Amitai, Yaakov
• Granted Patent: US 9,804,396 B2
• Time in Patent Office: Days
• US Class Current: 349/11
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: G02B 2027/0125 Field-of-view increase by wavefront division
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 2027/0187 slaved to motion of at least a part of the body of the user, e.g. head, eye
• CPC Class Codes: G02B 27/0081 with means for altering, e.g. enlarging, the entrance or exit pupil
• CPC Class Codes: G02B 27/0093 with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 27/0179 Display position adjusting means not related to the information to be displayed
• CPC Class Codes: G02B 27/141 using dichroic mirrors
• CPC Class Codes: G02B 27/145 having sequential partially reflecting surfaces
• CPC Class Codes: G02B 27/286 for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34

Abstract

Head-mounted display with an eye-tracking system and including a light-transmitting substrate (20) having two major surfaces and edges, optical means for coupling light into said substrate (20) by total internal reflection, partially-reflecting surfaces (22a-22c) carried by the substrate (20) that are not parallel with the major surfaces of the substrate (20), a near-infrared light source (78) and a display source (92) projecting within the photopic spectrum, wherein light from the light source (78) and light from the display source (92) are coupled into the substrate (20) by total internal reflection.

Claims

1. An optical system, comprising:

a light-transmitting substrate having at least two major surfaces and edges;

at least one optical means for coupling light waves into the substrate by total internal reflection;

at least two partially reflecting surfaces carried by the substrate wherein the partially reflecting surfaces are not parallel to the main surfaces of the substrate;

at least one light source projecting light waves located within a first optical spectrum, and

at least one display source projecting light waves located within a second optical spectrum, characterized in that the light waves from the light source and light waves from the display source are coupled into the substrate by total internal reflection.

2. The optical system according to claim 1, wherein the first optical spectrum is different than the second optical spectrum.

3. The optical system according to claim 1, wherein the first optical spectrum is in the near IR region.

4. The optical system according to claim 1, wherein the second optical spectrum is in the photopic range.

5. The optical system according to claim 1, wherein the light waves coupled inside the substrate are light waves of a first angular spectrum and a second angular spectrum, and wherein angles located within the first angular spectrum are smaller than angles located within the second angular spectrum.

6. The optical system according to claim 5, wherein a first partially reflecting surface is partially reflective for light waves located within the first optical spectrum and within the first angular spectrum, and substantially transparent for light waves located within the second optical spectrum and within the first and second angular spectrum.

7. The optical system according to claim 5, wherein a second partially reflecting surface is partially reflective for light waves located within the second optical spectrum and within the first angular spectrum, and substantially transparent for light waves located within the first optical spectrum and within the first and second angular spectrum and for light waves located within the second optical spectrum and within said second optical spectrum.

8. The optical system according to claims 6 and 7 claim 6, wherein the first and second partially reflecting surfaces couple light waves from the light source and the display source, respectively, out of the substrate into an eye of a viewer.

9. The optical system according to claim 6, wherein the first partially reflecting surface couples light waves reflected from the viewer'"'"'s eye and located within the first optical spectrum into the substrate, by total internal reflection.

10. The optical system according to claim 9, further comprising an eyeball tracker wherein the light source is part of the tracker.

11. The optical system according to claim 10, wherein the optical mean couples light waves reflected from the viewer'"'"'s eye out of the substrate into the eyeball tracker.

12. The optical system according to claim 11, further comprising an optical detector attached to, or embedded in, the eyeball tracker, wherein the light waves which are coupled into the eyeball tracker are focused into the detector.

13. The optical system according to claim 11, further comprising a first transmitting light guide, wherein light waves from the light source and from the display source are coupled into the substrate through the transmitting light guide.

14. The optical system according to claim 10, wherein the transmitting light guide is a polarizing beam-splitter.

15. The optical system according to claim 13, further comprising a second light source projecting light waves located in the second optical spectrum.

16. The optical system according to claim 15, further comprising a second transmitting light guide, wherein light waves from the first light source and from the second light source are coupled into the first transmitting light guide through the second transmitting light guide.

17. The optical system according to claim 16, wherein the second transmitting light guide is a dichroic beam-splitter.

18. The optical system according to claim 15, wherein the display source is an LCOS.

19. The optical system according to claim 18, wherein the LCOS is illuminated by light waves from the second light source.

20. The optical system according to claim 1, further comprising an optical filter located at the means for coupling light waves into the substrate.

21. The optical system according to claim 20, wherein the optical filter is reflective for the first optical spectrum and is substantially transparent for the second optical spectrum.

22. The optical system according to claim 20, wherein the optical filter is reflective for the second optical spectrum and is substantially transparent for the first optical spectrum.

23. The optical system according to claim 1, wherein the first and second partially reflecting surfaces are laterally separated from each other.

24. The optical system according to claim 1, wherein the first and second partially reflecting surfaces are located adjacent to each other.

25. The optical system according to claim 1, wherein at least one surface of the array of partially reflecting surfaces is partially reflective for light waves located within the second optical spectrum and within the first angular spectrum, and substantially transparent for light waves located within the first optical spectrum and within the first and second angular spectrum and for light waves located within the second optical spectrum and within the second angular spectrum.

26. The optical system according to claim 1, further comprising a second optical means for coupling light waves into the substrate by total internal reflection, wherein light waves from the first light source and light waves from the display source are coupled into the substrate by total internal reflection by the first and second optical means, respectively.

27. The optical system according to claim 26, wherein light waves from the first light source and light waves from the display source impinge on one of the two optical means at a given incident angle, and wherein one of the two optical means has high reflectance for light waves in the photopic range at said incident angle and high transmittance for light waves from the first light source at the incident angle.

28. The optical system according to claim 26, wherein light waves from the first light source and light waves from the display source impinge on one of the two optical means at a given incident angle, and wherein one of the two optical means has high transmittance for the light waves in the photopic range at said incident angle and high reflectance for light waves from the first light source at the incident angle.

29. The optical system according to claim 10, wherein the eyeball tracker detects blinking patterns of a viewer.

30. The optical system according to claim 29, wherein the eyeball tracker serves as a drowsy driver alerting unit.