AIR SPACED OPTICAL ASSEMBLY WITH INTEGRATED EYE TRACKING

• US 20180157320A1
• Filed: 12/01/2016
• Published: 06/07/2018
• Est. Priority Date: 12/01/2016
• Status: Abandoned Application

• Current Assignee: META Platforms Technologies LLC (Meta Platforms, Inc. (f/k/a Facebook, Inc.))
• Original Assignee: Oculus VR, LLC (Meta Platforms, Inc. (f/k/a Facebook, Inc.))
• Inventors: Trail, Nicholas Daniel
• Application Number:
  US15/366,412
• Publication Number:
  US 20180157320A1
• Time in Patent Office: Days
• 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: G06F 3/011 Arrangements for interaction with the human body, e.g. for user immersion in virtual reality blind teaching G09B21/00
• CPC Class Codes: G06F 3/013 Eye tracking input arrangements G06F3/015 takes precedence
• CPC Class Codes: G06V 40/19 Sensors therefor

Abstract

A head-mounted display (HMD) includes a display, an optical assembly and an eye tracking system that determines user'"'"'s eye tracking information. The optical assembly comprises a front optical element in series with a back optical element adjacent to the display. One surface of the back optical element is coated to reflect infrared (IR) light. The eye tracking system includes an illumination source and an imaging device positioned between the front optical element and the back optical element. The illumination source emits IR light that illuminates the coated surface and reflects towards the user'"'"'s eye. The imaging device captures an image of the user'"'"'s eye based on light reflected from the user'"'"'s eye and from the coated surface. The eye tracking information is determined based on the captured image. The HMD adjusts presentation of images displayed on the display, based on the eye tracking information.

Claims

1. A head-mounted display (HMD) comprising:

an electronic display;

an optical assembly comprising a front optical element in series with a back optical element adjacent to the electronic display, the back optical element comprises a first surface adjacent to the electronic display and a second surface opposite to the first surface configured to reflect light of a defined range of wavelengths;

an illumination source positioned between the front optical element and the back optical element, the illumination source configured to illuminate the second surface of the back optical element with light having one or more wavelengths within the defined range of wavelengths;

an imaging device positioned between the front optical element and the back optical element, the imaging device configured to capture an image of a user'"'"'s eye illuminated with light emitted from the illumination source having the one or more wavelengths reflected from the second surface of the back optical element; and

a controller coupled to the imaging device, the controller configured to determine an orientation of the user'"'"'s eye based on the captured image, and

wherein the system is configured to adjust presentation of one or more images displayed on the electronic display, based on the determined orientation of the user'"'"'s eye.

2. The HMD of claim 1, further comprising:

a varifocal module configured to adjust presentation of the one or more images displayed on the electronic display by adjusting focus of the one or more images based on the determined orientation of the user'"'"'s eye.

3. The HMD of claim 1, further comprising:

a varifocal module configured to adjust presentation of the one or more images displayed on the electronic display by performing foveated rendering of the one or more images based on the determined orientation of the user'"'"'s eye.

4. The HMD of claim 1, further comprising:

a varifocal module configured to adjust presentation of the one or more images displayed on the electronic display by adjusting position of at least one of the electronic display, the front optical element and the back optical element, based on the determined orientation of the user'"'"'s eye.

5. The HMD of claim 1, wherein at least one of the electronic display, the front optical element and the back optical element is configured to be movable to dynamically vary focus of the one or more images displayed on the electronic display.

6. The HIVID of claim 1, wherein the illumination source emits a structured light, spatially or temporally, the structured light being folded into an optical path by reflecting off of the second surface of the back optical element, and the structured light having a wavelength within the defined range of wavelengths.

7. The HMD of claim 1, wherein the illumination source comprises a plurality of emitters.

8. The HMD of claim 1, wherein:

the light having the one or more wavelengths reflected from the second surface of the back optical element comprises infrared (IR) light; and

the imaging device comprises a camera configured to capture images in the IR.

9. The HIVID of claim 1, wherein the defined range of wavelengths comprises one or more wavelengths larger than 750 nm.

10. The HIVID of claim 1, wherein the illumination source and the imaging device are positioned outside of a transmitted optical path of the user'"'"'s eye.

11. The HIVID of claim 1, wherein the second surface is coated to reflect light of the defined range of wavelengths and transmit visible light.

12. The HIVID of claim 1, wherein a shape of the second surface is spherical, aspherical, or free-form.

13. The HIVID of claim 1, wherein:

a portion of the second surface is coated;

the illumination source is configured to illuminate only the coated portion of the second surface; and

the coated portion of the second surface reflects light of the defined range of wavelengths towards the user'"'"'s eye and the imaging device.

14. The HMD of claim 1, wherein a Fresnel lens is positioned on the first surface of the back optical element in an optical path of the user'"'"'s eye and configured to correct aberration when outputting light of the one or more images to the user'"'"'s eye.

15. The HMD of claim 1, wherein the optical assembly is telecentric.

16. The HIVID of claim 1, wherein the imaging device is oriented to capture the image of the user'"'"'s eye illuminated with the light reflected from the user'"'"'s eye and then from the second surface of the back optical element.

17. A head-mounted display (HMD) comprising:

an electronic display configured to emit image light;

an optical assembly comprising a front optical element in series with a back optical element adjacent to the electronic display, the back optical element comprises a first surface adjacent to the electronic display and a second surface opposite to the first surface configured to reflect light of a defined range of wavelengths;

an eye tracking system that determines eye tracking information for a first eye of a user of the HIVID, the eye tracking system comprising;

an illumination source positioned between the front optical element and the back optical element, the illumination source configured to illuminate the second surface of the back optical element with light having one or more wavelengths within the defined range of wavelengths,

an imaging device positioned between the front optical element and the back optical element, the imaging device configured to capture an image of a user'"'"'s eye illuminated with light emitted from the illumination source having the one or more wavelengths reflected from the second surface of the back optical element; and

a controller configured to determine eye tracking information associated with the user'"'"'s eye based on the captured image, and

wherein the HIVID adjusts presentation of one or more images displayed on the electronic display, based on the determined eye tracking information.

18. The HIVID of claim 17, further comprising:

a varifocal module configured to adjust presentation of the one or more images displayed on the electronic display by adjusting focus of the one or more images based on the determined eye tracking information.

19. The HIVID of claim 17, further comprising:

a varifocal module configured to adjust presentation of the one or more images displayed on the electronic display by performing foveated rendering of the one or more images based on the determined eye tracking information.

20. The HMD of claim 17, wherein the front optical element is replaceable and selected from a set of optical elements to correct for an optical prescription of the user, each optical element from the set having a different optical characteristic.

21. The HMD of claim 17, further comprising:

a varifocal module configured to compensate for a difference between an optical prescription of the user and an optical characteristic of the front optical element to provide optical correction to the image light.

22. The HMD of claim 17, wherein:

the light having the one or more wavelengths reflected from the second surface of the back optical element comprises infrared (IR) light; and

the imaging device comprises a camera configured to capture images in the IR.