Portable eye tracking device

• US 9,710,058 B2
• Filed: 05/19/2014
• Issued: 07/18/2017
• Est. Priority Date: 09/03/2013
• Status: Active Grant

• Current Assignee: Tobii Technology AB
• Original Assignee: Tobii Technology AB
• Inventors: Gustafsson, Simon, Kingbck, Anders, Cederlund, Markus
• Primary Examiner(s): Elahi, Shan
• Application Number:
  US14/281,676
• Publication Number:
  US 20150062323A1
• Time in Patent Office: 1,156 Days
• Field of Search: 348 78
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: G02B 2027/0138 comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 2027/014 comprising information/image processing systems
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• 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 27/017 Head mounted
• CPC Class Codes: G06F 3/013 Eye tracking input arrangements G06F3/015 takes precedence
• CPC Class Codes: G06T 2207/10152 Varying illumination
• CPC Class Codes: G06T 2207/30201 Face
• CPC Class Codes: G06T 7/74 involving reference images or patches
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04R 1/32 for obtaining desired directional characteristic only specially adapted for hearing aids H04R25/40
• CPC Class Codes: H04R 2201/40 Details of arrangements for obtaining desired directional characteristic by combining a number of identical transducers covered by H04R1/40 but not provided for in any of its subgroups

Abstract

A portable eye tracker device is disclosed which includes a frame, at least one optics holding member, and a control unit. The frame may be adapted for wearing by a user. The at least one optics holding member may include at least one illuminator configured to selectively illuminate at least a portion of at least one eye of the user, and at least one image sensor configured to capture image data representing images of at least a portion of at least one eye of the user. The control unit may be configured to control the at least one illuminator for the selective illumination of at least a portion of at least one eye of the user, receive the image data from the at least one image sensor, and calibrate at least one illuminator, at least one image sensor, or an algorithm of the control unit.

Claims

1. A portable eye tracker device comprising:

a frame adapted for wearing by a user;

at least one optics holding member, wherein the optics holding member comprises;

at least one illuminator configured to selectively illuminate at least a portion of at least one eye of the user; and

at least one image sensor configured to capture image data representing images of at least a portion of at least one eye of the user; and

a control device configured to;

control the at least one illuminator for the selective illumination of at least a portion of at least one eye of the user;

receive the image data from the at least one image sensor;

calibrate at least one illuminator, at least one image sensor, or an algorithm of the control device, wherein the algorithm of the control device is stored in a memory device and executable by a processor to determine a gaze target area; and

determine the gaze target area for the user based at least in part on the image data.

2. The portable eye tracker device of claim 1, further comprising:

a scene camera facing away from the user and configured to capture image data representing images of at least a portion of the user'"'"'s field of view.

3. The portable eye tracker device of claim 2, wherein the control device is further configured to:

determine the gaze target area within the image data representing images of at least a portion user'"'"'s field of view wherein the gaze target area comprises less than ten percent of the image data in an image from the scene camera; and

control the scene camera to adjust at least one of focus or light sensitivity based on the gaze target area.

4. The portable eye tracker device of claim 2, wherein the control device is further configured to:

receive image data from the scene camera;

determine, automatically, a specific pattern or item is within the image data received from the scene camera; and

calibrate at least one illuminator, at least one image sensor, or the algorithm of the control device based at least in part on the image data having the specific pattern or item.

5. The portable eye tracker device of claim 4, wherein the specific pattern is displayed on a printed medium or provided by a display device.

6. The portable eye tracker device of claim 1, wherein calibrating at least one of the plurality of illuminators or at least one of the plurality of image sensors comprises a selection from a group consisting of:

adjusting a brightness of at least one illuminator;

determining an offset between a calculated gaze direction and an actual gaze direction;

determining a value of a parameter used by the algorithm of the control device;

adjusting a wavelength of light produced by at least one illuminator;

adjusting a sensitivity of at least one image sensor;

adjusting a focus of at least one image sensor; and

changing at least one parameter of the algorithm of the control device.

7. The portable eye tracker device of claim 1, further comprising:

a movement sensor configured to determine movement of the frame.

8. The portable eye tracker device of claim 1, wherein the control device is further configured to:

calibrate at least one illuminator, at least one image sensor, or a value of a parameter used by the algorithm of the control device.

9. The portable eye tracker device of claim 7, wherein the control device is further configured to:

determine the gaze target area for the user further based at least in part on the image data and information received from the movement sensor.

10. The portable eye tracker device of claim 1, wherein the control device is further configured to:

control at least one of illuminator to selectively illuminate at least a portion of at least one eye of the user using a light of a first wavelength;

receive a first set of image data from at least one image sensor, wherein the first set of image data represents images of at least a portion of at least one eye of the user captured when the user'"'"'s eye is exposed to the light of the first wavelength;

determine that the gaze target area cannot be determined based on the first set of image data;

receive information about ambient light illuminating at least a portion of at least one of the user;

determine a second wavelength based on the information about the ambient light, wherein the second wavelength is the same or different than the first wavelength;

control at least one of illuminator to selectively illuminate at least a portion of at least one eye of the user using a light of a second wavelength;

receive a second set of image data from at least one image sensor, wherein the second set of image data represents images of at least a portion of at least one eye of the user captured when the user'"'"'s eye is exposed to the light of the second wavelength; and

determine the gaze target area for the user based at least in part on the second set of image data.

11. The portable eye tracker device of claim 1, wherein the control device is further configured to:

control a first subset of the at least one illuminator to selectively illuminate at least a portion of at least one eye of the user;

receive a first set of image data from at least one image sensor of the first subset, wherein the first set of image data represents images of at least a portion of at least one eye of the user captured when at least one eye of the user is exposed to light from the first subset of the at least one illuminator;

determine that the gaze target area cannot be determined based on the first set of image data;

control a second subset of the at least one illuminator to selectively illuminate at least a portion of at least one eye of the user;

receive a second set of image data from at least one image sensor of the second subset, wherein the second set of image data represents images of at least a portion of at least one eye of the user captured when at least one eye of the user is exposed to light from the second subset of the at least one illuminator; and

determine the gaze target area for the user based at least in part on the second set of image data.

12. The portable eye tracker device of claim 1, wherein:

the portable eye tracker device further comprises a positioning device configured to determine a position of the portable eye tracker device; and

the control device is further configured to determine the gaze target area for the user based at least in part on the image data and information received from the positioning device.

13. The portable eye tracker device of claim 1, wherein the control device is further configured to:

receive image data from at least one image sensor;

determine a level of ambient light from the image data;

adjust a brightness or exposure time of at least one illuminator based at least in part on the level of ambient light.

14. The portable eye tracker device of claim 1, further comprising:

a display viewable by the user.

15. The portable eye tracker device of claim 1, wherein the control device is further configured to:

receive image data from at least one image sensor representing images including areas besides the user'"'"'s eyes.

16. A method of determining a gaze direction for a user, comprising:

activating, with a control device, at least one illuminator on a frame worn by a user to selectively illuminate at least a portion of at least one of the user'"'"'s eyes;

receiving, with the control device, image data representing images at least a portion of at least one of the user'"'"'s eyes from at least one image sensor on the frame;

calibrating, with the control device, at least one illuminator, at least one image sensor, or an algorithm of the control device, wherein the algorithm of the control device is stored in a memory device and executable by a processor to determine a gaze target area;

determining the gaze target area for the user based at least in part on the image data.

17. The method of claim 16, further comprising:

receiving image data from a scene camera configured to capture image data representing images of at least a portion of a view of the user;

determining, automatically, a specific pattern or item is within the image data received from the scene camera; and

calibrating at least one illuminator, at least one image sensor, or the algorithm of the control device based at least in part on the image data having the specific pattern or item.

18. A non-transitory machine readable medium having instructions thereon for determining a gaze direction for a user, the instructions executable by a processor for at least:

activating at least one illuminator on a frame worn by a user to selectively illuminate at least a portion of at least one of the user'"'"'s eyes;

receiving image data representing images at least a portion of at least one of the user'"'"'s eyes from at least one image sensor on the frame;

calibrating at least one illuminator, at least one image sensor, or an algorithm of a control device, wherein the algorithm of the control device is stored in a memory device and executable by a processor to determine a gaze target area; and

determining the gaze target area for the user based at least in part on the image data.

19. The non-transitory machine readable medium of claim 18, wherein the instructions are further executable for at least:

receiving image data from a scene camera configured to capture image data representing images of at least a portion of a view of the user;

determining, automatically, a specific pattern or item is within the image data received from the scene camera; and

calibrating at least one illuminator, at least one image sensor, or the algorithm of the control device based at least in part on the image data having the specific pattern or item.