Eye tracking system having an array of photodetectors aligned respectively with an array of pixels

• US 5,331,149 A
• Filed: 12/04/1992
• Issued: 07/19/1994
• Est. Priority Date: 12/31/1990
• Status: Expired due to Term

• Current Assignee: Kopin Corporation
• Original Assignee: Kopin Corporation
• Inventors: Spitzer, Mark B., Jacobsen, Jeffrey
• Primary Examiner(s): Nelms, David C.
• Assistant Examiner(s): LE, QUE TAN
• Application Number:
  US07/985,285
• Time in Patent Office: 592 Days
• Field of Search: 250/221, 250/214.1, 250/214 R, 250/561, 345/7-9, 359/630, 359/482, 359/858, 358/107, 358/109, 358/113
• US Class Current: 250/221
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: G02B 2027/0132 comprising binocular systems
• CPC Class Codes: G02B 2027/0138 comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 2027/0187 slaved to motion of at least a part of the body of the user, e.g. head, eye
• CPC Class Codes: G02B 2027/0198 System for aligning or maintaining alignment of an image in a predetermined direction
• 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 5/30 Polarising elements light-modulating devices with active elements G02F1/00
• CPC Class Codes: G02F 1/13613 the semiconductor element being formed on a first substrate and thereafter transferred to the final cell substrate
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G09G 2300/023 Display panel composed of stacked panels
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2340/0464 Positioning
• CPC Class Codes: G09G 2370/042 for monitor identification
• CPC Class Codes: G09G 3/30 using electroluminescent panels
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: G09G 3/36 : using liquid crystals
• CPC Class Codes: G09G 3/3607 : for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/3614 : Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 : using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: H01L 21/8221 : Three dimensional integrated circuits stacked in different levels
• CPC Class Codes: H01L 2221/68359 : used as a support during manufacture of interconnect decals or build up layers
• CPC Class Codes: H01L 24/96 : the devices being encapsulated in a common layer, e.g. neo-wafer or pseudo-wafer, said common layer being separable into individual assemblies after connecting
• CPC Class Codes: H01L 25/0756 : Stacked arrangements of devices
• CPC Class Codes: H01L 25/10 : the devices having separate containers
• CPC Class Codes: H01L 25/50 : Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 27/0688 : Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 27/1214 : comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1266 : the substrate on which the devices are formed not being the final device substrate, e.g. using a temporary substrate
• CPC Class Codes: H01L 27/146 : Imager structures
• CPC Class Codes: H01L 27/156 : two-dimensional arrays
• CPC Class Codes: H01L 29/786 : Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785
• CPC Class Codes: H01L 29/78603 : characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01077 : Iridium [Ir]
• CPC Class Codes: H01L 2924/04953 : TaN
• CPC Class Codes: H01L 2924/10329 : Gallium arsenide [GaAs]
• CPC Class Codes: H01L 2924/10336 : Aluminium gallium arsenide [AlGaAs]
• CPC Class Codes: H01L 2924/1204 : Optical Diode
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01S 5/0217 : Removal of the substrate
• CPC Class Codes: H01S 5/423 : having a vertical cavity
• CPC Class Codes: H04N 5/70 : Circuit details for electroluminescent devices
• CPC Class Codes: H04N 5/7441 : the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 5/7491 : of head mounted projectors
• CPC Class Codes: H04N 9/3141 : Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: H05B 33/12 : Light sources with substantially two-dimensional radiating surfaces

Abstract

An eye tracking system is disclosed which is comprised of an eye tracking module formed of a display joined to a photodetector array. Each pixel in the display is aligned with a corresponding photodetector. An image generated by the display is projected onto a viewing screen or toward a viewer. Axial light rays from the display pixels are reflected by the eye and detected by a respective photodetector which generates an electrical signal indicative of eye position.

Claims

1. A system for determining the direction in which the eye of a viewer is looking comprising:

a) a viewing screen for viewing an image;

b) a display comprising an array of pixels for projecting said image on the viewing screen in a transmit optical path;

c) an array of photodetectors located adjacent the display for detecting light emanating from the display pixels and reflected from the eye of the viewer and returning along the transmit optical path.

2. The system of claim 1 in which the display is a flat panel display taken from the group comprising an electroluminescent, liquid crystal or dot matrix displays.

3. The system of claim 1 in which the display is a flat panel display formed of a back panel with an active matrix array of pixels formed of Si thin film transistors transferred onto said back panel, a front display panel and liquid crystal material enclosed between the front and back panels;

and the array of photodetectors is comprised of a diode array of III-V diodes transferred on to said front panel.

4. The system of claim 1 wherein the screen comprises a visor through which the viewer can view an external scene and upon which the display image may be superimposed upon the external scene.

5. The system of claim 4 wherein a frequency rejection filter is formed on the external side of the screen and a narrow pass-band frequency filter for passing the frequencies rejected by the rejection filter is formed on the photodetector array.

6. The system of claim 4 wherein the light from the display signals is polarized in one plane and the light from the external scene is polarized in an opposite plane.

12. The module of claim 4 in which the photodetectors of the array are interconnected in a common parallel circuit.

7. A detector/display module comprising:

a flat panel display comprised of a front panel and a back panel and a display array of pixels disposed between said panels with an array of photodetectors disposed on one of said panels and wherein said photodetectors are aligned with a respective pixel of the display array.

8. The module of claim 7 in which the photodetectors are formed of III-V materials.

9. The module of claim 7 wherein the photodetectors are formed on a thin film of III-V material and transferred to a carrier and then transferred onto one of the panels.

10. The module of claim 7 wherein the array of photodetectors are disposed on the front panel.

11. The module of claim 7 wherein the display is an AMLCD, or EL display.

13. A system for determining the line-of-sight position of the eye of a viewer while receiving an image projected on a screen by a display and revising said image in response to said determinations comprising:

a) a viewing screen for viewing said image;

b) a display comprising an array of pixels for projecting said image onto the viewing screen;

c) an array of photodetectors, each such photodetector being aligned with a respective pixel, for converting light from the pixels reflected by the eye into an electrical signal indicative of line-of-sight position;

d) a computer responsive to said electrical signal for generating a video signal for revising said image.

14. The system of claim 13 including a control device coupled to said computer and responsive to line-of-sight electrical signals generated by said computer.

15. A method of determining the direction in which an eye of a viewer is looking comprising the steps of:

a) forming an image on a viewing screen for viewing by the eye of a viewer by projecting light from a display onto said screen;

b) detecting light emanating from the display and reflected from the eye of the viewer and returned along the transmit optical path.

16. The method of claim 15 wherein the viewing screen comprises a visor through which the viewer can see an external scene and the image is superimposed upon the viewing screen.

17. The method of claim 15 wherein the image comprises a cursor and the image is projected at a predetermined frequency and further comprising the steps of filtering frequencies other than the projected image frequency for viewing on the viewing screen.

18. The method of claim 16 further comprising the steps of polarizing the projected light in one plane and polarizing the light from the external scene in an opposite plane.

19. A method of determining the line-of-sight position of the eye of a viewer while receiving an image projected on a screen by a display and revising said image in response to said determinations comprising the steps of:

a) projecting said image onto the viewing screen for viewing by the eye using a display comprising an array of pixels;

b) providing an array of photodetectors with each photodetector aligned with a respective pixel, and converting light from the pixels reflected by the eye into a electrical signal indicative of line-of-sight position; and

c) generating a video signal responsive to said electrical signal for revising said image.

20. A system for determining the direction in which the eye of a viewer is looking with respect to an image from a display comprising:

a) a display comprising an array of pixels for projecting said image in a transmit optical path;

b) an array of photodetectors located adjacent the display for detecting light emanating from the display pixels and reflected from the eye of a viewer and returning in a reverse direction along the transmit optical path.

21. The system of claim 20 in which the display is a flat panel display taken from the group comprising an electroluminescent, liquid crystal or dot matrix displays.

22. The system of claim 20 in which the display is a flat panel display formed of a back panel with an active matrix array of pixels formed of Si thin film transistors transferred onto said back panel, a front display panel and liquid crystal material enclosed between the front and back panels;

and the array of photodetectors is comprised of a diode array of III-V diodes transferred on to said front panel.

23. A system for determining the line-of-sight position of the eye of a viewer while receiving an image from a display and revising said image in response to said determinations comprising:

a) a display comprising an array of pixels for projecting said image onto the viewer;

b) an array of photodetectors, each such photodetector being aligned with a respective pixel, for converting light from the pixels reflected by the eye into an electrical signal indicative of line-of-sight position;

c) a computer responsive to said electrical signal for generating a video signal for revising said image.

24. The system of claim 23 including a control device coupled to said computer and responsive to line-of-sight electrical signals generated by said computer.

25. A method of determining the direction in which an eye of a viewer is looking comprising the steps of:

a) forming an image for viewing by the eye of a viewer by projecting light from pixels of a display;

b) detecting the light emanating from the display and reflected from the eye of the viewer with photodetectors formed adjacent respective pixels; and

c) determining the direction of the eye by sensing which detectors detect the reflected light.

26. The method of claim 25 wherein the image comprises a cursor and the image is projected at a predetermined frequency and further comprising the steps of filtering frequencies other than the projected image frequency for viewing by the viewer.

27. The method of claim 26 further comprising the steps of polarizing the projected light in one plane and polarizing the light from an external scene in an opposite plane.

28. A method of determining the line-of-sight position of the eye of a viewer while receiving an image projected by a display and revising said image in response to said determinations comprising the steps of:

a) projecting said image for viewing by the eye using a display comprising an array of pixels;

b) providing an array of photodetectors with each photodetector aligned with a respective pixel,. and converting light from the pixels reflected by the eye into a electrical signal indicative of line-of-sight position; and

c) generating a video signal responsive to said electrical signal for revising said image.