Compact eye-tracked head-mounted display
View Patent ↗Eye-tracked head-mounted displays are provide which, in one aspect, may utilize the same optics for eyetracking and image viewing, with a selected portion of the optics used for an eyetracking optical path and a selected portion of the display optics used for an image viewing optical path.
1. An eye-tracked head-mounted display, comprising:
a micro-display for generating an image to be viewed by a user, the micro-display having a display optical path and an exit pupil associated therewith;
a first plane located at the micro-display and a second plane located at the exit pupil;
an image sensor configured to receive reflected optical radiation from the second plane reflected from a user's eye positioned thereat, the image sensor having a sensor optical path associated therewith; and
display optics disposed in optical communication with the micro-display along the display optical path and in optical communication with the image sensor along the sensor optical path, the display optics having a selected surface closest to the micro-display and the image sensor, the display optics located relative to the micro-display and image sensor such that the display and image sensor optical paths impinge upon differing respective portions of the selected surface,
wherein the display optical path and sensor optical path each comprise respective optical axes at the display optics and image sensor, respectively, and wherein the optical axes are tilted relative to one another at the second plane.
2. The eye-tracked head-mounted display according to claim 1 , wherein the display and image sensor optical paths partially overlap at the selected surface.
3. The eye-tracked head-mounted display according to claim 1 , wherein the display optics is configured to create a virtual image of the micro-display for viewing at the second plane.
4. The eye-tracked head-mounted display according to claim 1 , wherein the display optical path comprises an optical axis, and wherein the image sensor is located off the optical axis of the display optical path.
5. The eye-tracked head-mounted display according to claim 1 , wherein the display optical path comprises an optical axis, and wherein the micro-display is located on the optical axis of the display optical path.
6. The eye-tracked head-mounted display according to claim 1 , comprising a stop at the first plane, the stop having at least one aperture therein disposed at a location along the sensor optical path.
7. The eye-tracked head-mounted display according to claim 6 , wherein the at least one aperture comprises a pin-hole.
8. The eye-tracked head-mounted display according to claim 1 , comprising a stop having at least one aperture therein disposed at a location along the sensor optical path between the sensor and selected surface.
9. The eye-tracked head-mounted display according to claim 1 , wherein the display optics comprises a freeform optical element.
10. The eye-tracked head-mounted display according to claim 1 , wherein the display optics comprises a rotationally symmetric optical element.
11. The eye-tracked head-mounted display according to claim 1 , wherein the display optics comprises a freeform optical prism.
12. The eye-tracked head-mounted display according to claim 11 , wherein the prism comprises a wedge-shaped prism.
13. The eye-tracked head-mounted display according to claim 11 , wherein the prism comprises an aspheric surface.
14. The eye-tracked head-mounted display according to claim 11 , wherein the prism is telecentric in display space.
15. The eye-tracked head-mounted display according to claim 11 , wherein the prism is non-telecentric in display space.
16. The eye-tracked head-mounted display according to claim 11 , wherein the prism comprises a TIR (total internal reflection) surface oriented to receive and totally internally reflect light from the micro-display.
17. The eye-tracked head-mounted display according to claim 11 , wherein the prism comprises a TIR (total internal reflection) surface oriented to totally internally reflect light to the image sensor.
18. The eye-tracked head-mounted display according to claim 11 , comprising a freeform corrective lens in optical communication with the prism.
19. The eye-tracked head-mounted display according to claim 18 , wherein field of view of the corrective lens is larger than a field of view of the display optics.
20. The eye-tracked head-mounted display according to claim 1 , wherein the display optics comprise a half-mirrored surface.
21. The eye-tracked head-mounted display according to claim 1 , comprising an illumination source for generating optical radiation and configured to illuminate the second plane to effect illumination of the user's eye, the illumination source having an illumination optical path associated therewith.
22. The eye-tracked head-mounted display according to claim 21 , wherein the display optics is disposed in optical communication with the illumination source along the illumination optical path.
23. The eye-tracked head-mounted display according to claim 21 , wherein the display optics is configured to receive radiation from the illumination source and transmit the radiation to the second plane.
24. The eye-tracked head-mounted display according to claim 21 , wherein the illumination source is located proximate the first plane.
25. The eye-tracked head-mounted display according to claim 21 , wherein the illumination source comprises a plurality of light emitting diodes.
26. The eye-tracked head-mounted display according to claim 21 , wherein the display optics is configured to collimate the optical radiation from the illumination source.
27. The eye-tracked head-mounted display according to claim 21 , wherein the display optical path of the display optics comprises an optical axis and the illumination source is located off the optical axis.
28. The eye-tracked head-mounted display according to claim 21 , wherein the prism comprises a TIR (total internal reflection) surface oriented to receive and totally internally reflect radiation from the illumination source.