Scanned retinal display with exit pupil selected based on viewer's eye position

• US 6,204,829 B1
• Filed: 03/27/2000
• Issued: 03/20/2001
• Est. Priority Date: 02/20/1998
• Status: Expired due to Term

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Tidwell, Michael
• Primary Examiner(s): WU, XIAO MIN
• Application Number:
  US09/536,481
• Time in Patent Office: 358 Days
• Field of Search: 345/7, 345/8, 345/9, 359/630, 359/631, 359/632, 359/633, 359/13, 359/14, 359/199, 340/980
• US Class Current: 345/7
• CPC Class Codes: G02B 26/101 with both horizontal and vertical deflecting means, e.g. raster or XY scanners colour television using laser beams scanning a display screen H04N9/3129
• 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 7/287 including a sight line detecting device
• CPC Class Codes: G06F 3/013 Eye tracking input arrangements G06F3/015 takes precedence

Abstract

A scanned retinal display includes an optical scanning array to generate multiple exit pupils in conjunction with an eyepiece. The multiple exit pupils expand the effective exit pupil. As a user moves their eye the eye moves from one exit pupil to another. A scanning array creates the multiple exit pupils to maintain a clear line of sight for an augmented display. Also, a viewer'"'"'s eye position is tracked. To achieve a larger effective exit pupil and the pin hole effect advantage of a small exit pupil, only one exit pupil of the multiple pupils is active to enter the user'"'"'s eye.

Claims

1. A retinal display apparatus for producing a scanned image for viewing by a viewer'"'"'s eye in response to an image data signal, comprising:

a light source for generating light, wherein the light is modulated as a function of the image data signal to define image content;

an optical scanner array having a plurality of light reflecting surfaces, the light reflecting surfaces moving at a substantially common frequency with each of the other light reflecting surfaces of the plurality of light reflecting surfaces, wherein light originating from the light source impinges in parallel upon each one light reflecting surface of the plurality of light reflecting surfaces, and wherein light is redirected by each respective one of the plurality of light reflecting surfaces along a corresponding one of a plurality of optical paths;

an eyepiece, positioned along the plurality of optical paths between the eye and the scanner array, receiving the redirected light from each one of the plurality of light reflecting surfaces to form a plurality of respective exit pupils through which the image is scanned, wherein there is a one to one correspondence between each one exit pupil of the plurality of exit pupils and a corresponding one optical path of the plurality of optical paths and a corresponding one light reflecting surface of the plurality of light reflecting surfaces; and

an eye tracker which determines position of a viewer'"'"'s eye, wherein the image is scanned onto the viewer'"'"'s eye through one exit pupil of the plurality of exit pupils, said one exit pupil selected based upon the position of the viewer'"'"'s eye determined by the eye tracker.

2. The apparatus of claim 1, wherein the light source generates multiple beams, each one of the multiple beams impinging on a corresponding one of the plurality of light reflecting surfaces.

3. The apparatus of claim 1, wherein the viewer has a line of sight which is a combination of a real world view of the viewer'"'"'s ambient environment augmented with the scanned image to form an augmented view, the augmented view achieved by locating the light source and optical scanner out of the viewer'"'"'s direct line of sight.

4. A retinal display apparatus for producing a scanned image for viewing by a viewer'"'"'s eye in response to an image data signal, comprising:

a plurality of light sources for generating respective light beams, wherein each respective light beam is modulated as a function of the image data signal to define image content;

an optical scanner array having a plurality of light reflecting surfaces, each of the light reflecting surfaces moving at a respective frequency, wherein the light beam from each respective light source impinges upon a respective one of the plurality of light reflecting surfaces and is redirected along a respective optical path of a plurality of optical paths, wherein each respective light source generates the respective light beam synchronized to the frequency of motion of a corresponding one of the respective light reflecting surfaces;

an eyepiece positioned along the plurality of optical paths between the eye and the scanner array receiving the redirected light respectively from each one of the plurality of light reflecting surfaces to form a plurality of corresponding exit pupils through which the image is scanned, wherein there is a one to one correspondence between each one exit pupil of the plurality of exit pupils and a corresponding one optical path of the plurality of optical paths and a corresponding one light reflecting surface of the plurality of light reflecting surfaces; and

an eye tracker which determines position of a viewer'"'"'s eye, wherein the image is scanned onto the viewer'"'"'s eye through one exit pupil of the plurality of exit pupils, said one exit pupil selected based upon the position of the viewer'"'"'s eye determined by the eye tracker.

5. The apparatus of claim 4, wherein the viewer has a line of sight which is a combination of a real world view of the viewer'"'"'s ambient environment augmented with the scanned image to form an augmented view, the augmented view achieved by locating the light source and optical scanner out of the viewer'"'"'s direct line of sight.

6. A method for generating an exit pupil for a retinal display device, the retinal display device receiving an image data signal and scanning an image derived from the image data signal upon a viewer'"'"'s eye, the method comprising the steps of:

generating light modulated as a function of the image data signal to define image content;

receiving the modulated light at an optical scanner array having a plurality of light reflecting surfaces, the light reflecting surfaces moving at a substantially common frequency, the light impinging in parallel upon each one light reflecting surface of the plurality of light reflecting surfaces, the impinging light being redirected by each respective one of the plurality of light reflecting surfaces along a corresponding one of a plurality of optical paths;

receiving the redirected light from each one of the plurality of light reflecting surfaces at an eyepiece;

forming with the eyepiece a plurality of exit pupils from the light received, respectively, from the plurality of light reflecting surfaces, wherein each one exit pupil of the plurality of exit pupils is formed from the light received at the eyepiece from a corresponding one light reflecting surface of the plurality of light reflecting surfaces, wherein there is a one to one correspondence between each one exit pupil of the plurality of exit pupils and a corresponding one optical path of the plurality of optical paths and a corresponding one light reflecting surface of the plurality of light reflecting surfaces;

tracking eye position of the viewer'"'"'s eye;

determining, based on the tracked eye position, an exit pupil aligned with an entrance pupil of the viewer'"'"'s eye; and

scanning the modulated light onto the viewer'"'"'s eye through the aligned exit pupil.

7. The method of claim 6, wherein the viewer has a line of sight which is a combination of a real world view of the viewer'"'"'s ambient environment augmented with the scanned image to form an augmented view, the augmented view achieved by locating the optical scanner out of the viewer'"'"'s direct line of sight.