Virtual retinal display with eye tracking

• US 20020097498A1
• Filed: 02/15/2002
• Published: 07/25/2002
• Est. Priority Date: 01/20/1998
• Status: Active Grant

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Johnston, Richard S., Melville, Charles D.
• Granted Patent: US 6,560,028 B2
• Time in Patent Office: Days
• US Class Current: 359/630
• 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 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 7/287 including a sight line detecting device
• CPC Class Codes: G06V 40/18 Eye characteristics, e.g. of the iris
• CPC Class Codes: G06V 40/19 Sensors therefor
• CPC Class Codes: G09G 3/001 using specific devices not provided for in groups G09G3/02 - G09G3/36, e.g. using an intermediate record carrier such as a film slide; Projection systems; Display of non-alphanumerical information, solely or in combination with alphanumerical information, e.g. digital display on projected diapositive as background slide projectors per se G03B23/00 = 42 HP

Abstract

Light emitted from a virtual retinal display light source passes through a beamsplitter to a scanning subsystem and on to an eyepiece and the viewer'"'"'s eye. Some of the light is reflected from the viewer'"'"'s eye passing back along the same path. Such light however is deflected at the beamsplitter toward a photodetector. The reflected light is detected and correlated to the display scanner'"'"'s position. The content of the reflected light and the scanner position for such sample is used to generate a map of the viewer'"'"'s retina. Such map includes ‘landmarks’ such as the viewer'"'"'s optic nerve, fovea, and blood vessels. The map of the viewer'"'"'s retina is stored and used for purposes of viewer identification. The viewer'"'"'s fovea position is monitored to track where the viewer is looking

Claims

1. A display apparatus, comprising:

an image source for generating light;

a Tensing system having an input aligned to the image source for receiving the generated light, the Tensing system having an output adapted for transmitting light to a viewer'"'"'s eye, the Tensing system defining an optical path from the input to the output, the Tensing system comprising a variably transmissive eyepiece which maintains contrast between the transmitted light and an ambient lighting.

2. A display apparatus according to claim 1, in which the eyepiece comprises a photochromatic material which alters transmissiveness of the eyepiece according to a signal applied across the photochromatic material.

3. A display apparatus according to claim 2, further comprising a photosensor which detects ambient lighting and generates a bias voltage, said bias voltage applied across the photochromatic material as said signal.

4. A display apparatus according to claim 1, further comprising:

means responsive to ambient lighting for altering transmissiveness of the eyepiece.

5. A display apparatus according to claim 1, further comprising:

means for tracking orientation of a viewer'"'"'s eye.

6. A method of presenting information to a user, comprising:

generating light for presentation onto an eye of the user; and

receiving the generated light at a variably transmissive eyepiece which maintains contrast between the transmitted light and an ambient lighting.

7. A method according to claim 6, further comprising:

sensing ambient lighting; and

altering transmissiveness of the eyepiece in response to the sensed ambient lighting.

8. A method according to claim 7, wherein said altering comprises:

applying a bias voltage across a photochromatic material of the eyepiece.

9. A method according to claim 6, further comprising tracking orientation of the user'"'"'s eye.