Eye glint imaging in see-through computer display systems
Disclosure herein concerns a method that includes illuminating a user's eye with an illumination source in a head-worn display, capturing an image of the user's eye with an eye camera in the head-worn display, wherein the image includes an eye glint produced by light from the illumination source that is reflected from a surface of the user's eye, determining a size of an eye glint in the captured image, and identifying a change in focus distance for the user's eye in correspondence with a change in the size of the eye glint.
1. A wearable head device comprising:
an illumination source configured for illuminating an eye of a user of the wearable head device, wherein illuminating the eye produces an eye glint;
a camera configured for capturing an image of the eye, the captured image including an image of the eye glint; and
one or more processors configured to perform:
determining, based on at least the captured image, a change in size of the eye glint; and
determining a change in focus distance for the eye of the user based on the change in size of the eye glint.
2. The wearable head device of claim 1 , wherein:
the camera is configured for capturing a plurality of images of the eye of the user of the wearable head device, and
the determining, based on at least the captured image, a change in size of the eye glint comprises determining, based on the plurality of captured images of the eye, the change in size of the eye glint.
3. The wearable head device of claim 2 , wherein:
the illumination source is configured for illuminating an eye of a user of the wearable head device with light with a pattern, wherein illuminating the eye produces an eye glint based on the light with the pattern,
the plurality of captured images of the eye including images of the eye glint produced based on the light with the pattern, and
the determining, based on the plurality of captured images of the eye, the change in size of the eye glint comprises determining, based on the images of the eye glint produced based on the light with the pattern, the change in size of the eye glint.
4. The wearable head device of claim 3 , wherein:
the determining a change in focus distance for the eye of the user based on the change in size of the eye glint comprises determining, based on a size or a spacing of the pattern, the change in focus distance for the eye of the user.
5. The wearable head device of claim 1 , wherein the illumination source is configured for illuminating an eye of a user of the wearable head device with light of constant size.
6. The wearable head device of claim 1 , wherein the illumination source is configured for illuminating an eye of a user of the wearable head device with visible wavelength light.
7. The wearable head device of claim 1 , wherein the illumination source is configured for illuminating an eye of a user of the wearable head device with infrared wavelength light.
8. The wearable head device of claim 1 , wherein:
the change in focus distance for the eye of the user comprises an increase in focus distance for the eye, and
the change in size of the eye glint comprises an increase in size of the eye glint.
9. A method, comprising:
illuminating, via an illumination source of a wearable head device, an eye of a user of the wearable head device, wherein illuminating the eye produces an eye glint;
capturing, via a camera of the wearable head device, an image of the eye, the captured image including an image of the eye glint;
determining, based on at least the captured image, a change in size of the eye glint; and
determining a change in focus distance for the eye of the user based on the change in size of the eye glint.
10. The method of claim 9 , comprising:
capturing, via the camera of the wearable head device, a plurality of images of the eye of the user of the wearable head device,
wherein:
the determining, based on at least the captured image, a change in size of the eye glint comprises determining, based on the plurality of captured images of the eye, the change in size of the eye glint.
11. The method of claim 10 , wherein:
the illuminating an eye of a user of the wearable head device comprises illuminating the eye of the user of the wearable head device with light with a pattern, wherein illuminating the eye produces an eye glint based on the light with the pattern,
the plurality of captured images of the eye including images of the eye glint produced based on the light with the pattern, and
the determining, based on the plurality of captured images of the eye, the change in size of the eye glint comprises determining, based on the images of the eye glint produced based on the light with the pattern, the change in size of the eye glint.
12. The method of claim 11 , wherein:
the determining a change in focus distance for the eye of the user based on the change in size of the eye glint comprises determining, based on a size or a spacing of the pattern, the change in focus distance for the eye of the user.
13. The method of claim 9 , wherein:
the illuminating an eye of a user of the wearable head device comprises illuminating the eye of the user of the wearable head device with light of constant size.
14. The method of claim 9 , wherein:
the change in focus distance for the eye of the user comprises an increase in focus distance for the eye, and
the change in size of the eye glint comprises an increase in size of the eye glint.
15. A non-transitory computer-readable medium storing instructions that, when executed by one or more processors of a wearable head device, cause the one or more processors to perform a method, the method comprising:
illuminating, via an illumination source of the wearable head device, an eye of a user of the wearable head device, wherein illuminating the eye produces an eye glint;
capturing, via a camera of the wearable head device, an image of the eye, the captured image including an image of the eye glint;
determining, based on at least the captured image, a change in size of the eye glint; and
determining a change in focus distance for the eye of the user based on the change in size of the eye glint.
16. The non-transitory computer-readable medium of claim 15 , the method comprising:
capturing, via the camera of the wearable head device, a plurality of images of the eye of the user of the wearable head device,
wherein:
the determining, based on at least the captured image, a change in size of the eye glint comprises determining, based on the plurality of captured images of the eye, the change in size of the eye glint.
17. The non-transitory computer-readable medium of claim 16 , wherein:
the illuminating an eye of a user of the wearable head device comprises illuminating the eye of the user of the wearable head device with light with a pattern, wherein illuminating the eye produces an eye glint based on the light with the pattern,
the plurality of captured images of the eye including images of the eye glint produced based on the light with the pattern, and
the determining, based on the plurality of captured images of the eye, the change in size of the eye glint comprises determining, based on the images of the eye glint produced based on the light with the pattern, the change in size of the eye glint.
18. The non-transitory computer-readable medium of claim 17 , wherein:
the determining a change in focus distance for the eye of the user based on the change in size of the eye glint comprises determining, based on a size or a spacing of the pattern, the change in focus distance for the eye of the user.
19. The non-transitory computer-readable medium of claim 15 , wherein:
the illuminating an eye of a user of the wearable head device comprises illuminating the eye of the user of the wearable head device with light of constant size.
20. The non-transitory computer-readable medium of claim 15 , wherein:
the change in focus distance for the eye of the user comprises an increase in focus distance for the eye, and
the change in size of the eye glint comprises an increase in size of the eye glint.