Eye-tracking enabled wearable devices

Patent metadata

Field	Value
Publication number	US-10635169-B2
Application number	US-201815983772-A
Country	US
Kind code	B2
Filing date	May 18, 2018
Priority date	Sep 24, 2015
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

A system for determining a gaze direction of a user is disclosed. The system may include a first illuminator, a first profile sensor, and at least one processor. The first illuminator may be configured to illuminate an eye of a user. The first profile sensor may be configured to detect light reflected by the eye of the user. The processor(s) may be configured to determine a gaze direction of the user based at least in part on light detected by the first profile sensor.

First claim

What is claimed is:

1. A system for determining a gaze direction of a user, wherein the system comprises:
a lens;
a display device configured to be viewed through the lens,
a hot mirror;
a first illuminator configured to illuminate an eye of a user;
an area image sensor arranged behind the display device and configured to detect light reflected by the eye of the user, wherein the area image sensor has a sensitive area having a total number of pixels characterized by a total number of rows and a total number of columns; and
at least one processor configured to determine the gaze direction of the user based at least in part on light detected by the area image sensor;

wherein determining the gaze direction of the user based at least in part on light detected by the area image sensor comprises:
determining a location of a glint on the eye caused by light reflected by the eye of the user, based at least in part on a higher magnitude light level detected at one or more pixels of the area image sensor;
wherein the step of determining the gaze direction of the user based at least in part on light detected by the area image sensor further comprises the steps of:
determining magnitudes of light exposure at a subset of the total number of rows during one or more illumination periods;
determining magnitudes of light exposure at a subset of the total number of columns during one or more illumination periods;
based on the magnitudes of light exposure at the subset of the total number of rows and the magnitudes of light exposure at the subset of the total number of columns, identifying a subset of a total number of pixels of the area image sensor which include and surround the one or more pixels of the area image sensor which detected the higher magnitude light level; and
analyzing only the subset of the total number of pixels of the area image sensor during a subsequent determination of gaze direction during a subsequent illumination period.

2. A system according to claim 1 , wherein the hot mirror is a coating or film arranged atop the lens.

3. A system according to claim 1 , wherein said the hot mirror is applied directly onto the lens.

4. A system according to claim 1 , wherein said hot mirror is in a form of a separate piece.

5. A system according to claim 1 , wherein the hot mirror is arranged on a side of the lens facing the user.

6. A system according to claim 1 , wherein an illuminator is arranged atop the hot mirror.

7. A system according to claim 1 , wherein the illuminator is arranged atop the hot mirror via a separate piece of material such as glass or plastic.

8. A method for determining a gaze direction of a user, wherein the method comprises:
displaying, through a lens, an image to the user by using a display device;
at least in part preventing, light in the infrared spectrum emitted by the display device,
from passing the lens by using a hot mirror illuminating an eye of a user;
detecting, with an area image sensor arranged behind the display device, light reflected
by the eye of the user, wherein the area image sensor has a sensitive area having a total
number of pixels characterized by a total number of rows and a total number of columns;
determining, with at least one processor, the gaze direction of the user based at least in part on light detected by the area image sensor;
wherein determining the gaze direction of the user based at least in part on light detected by the area image sensor comprises:
determining a location of a glint on the eye caused by light reflected by the eye of the user, based at least in part on a higher magnitude light level detected at one or more pixels of the area image sensor;
wherein the step of determining the location of the glint on the eye caused by light reflected by the eye of the user, based at least in part on the higher magnitude light level detected at one or more pixels of the area image sensor further comprises the steps of:
determining magnitudes of light exposure at a subset of the total number of rows during one or more illumination periods;
determining magnitudes of light exposure at a subset of the total number of columns during one or more illumination periods;
based on the magnitudes of light exposure at the subset of the total number of rows and the magnitudes of light exposure at the subset of the total number of columns, identifying a subset of a total number of pixels of the area image sensor which include and surround the one or more pixels of the area image sensor which detected the higher magnitude light level; and
analyzing only the subset of the total number of pixels of the area image sensor during a subsequent determination of gaze direction during a subsequent illumination period.

9. A non-transitory machine readable medium comprising a computer program adapted to perform the method according to claim 8 .

Assignees

• Tobii Ab

Inventors

• Gustafsson Simon
• Tornéus Daniel Johansson
• Andersson Jonas
• Kron Johannes
• Skogö Mårten
• Biedert Ralf

Classifications

• G09G2340/0464

  Positioning · CPC title

• G06F2203/0381

  Multimodal input, i.e. interface arrangements enabling the user to issue commands by simultaneous use of input devices of different nature, e.g. voice plus gesture on digitizer · CPC title

• G02B27/017

  Head mounted · CPC title

• G02B2027/014

  comprising information/image processing systems · CPC title

• G02B2027/0187

  slaved to motion of at least a part of the body of the user, e.g. head, eye · CPC title