Eye-tracking device and display apparatus including the same

Patent metadata

Field	Value
Publication number	US-2020249754-A1
Application number	US-202016752114-A
Country	US
Kind code	A1
Filing date	Jan 24, 2020
Priority date	Feb 5, 2019
Publication date	Aug 6, 2020
Grant date	—

Abstract

Provided are an eye-tracking device that may rapidly and accurately track an observer's eye and may be made compact, and a display apparatus including the eye-tracking device. The eye-tracking device includes: a light source configured to emit an illumination light; a light guide plate configured to transmit the illumination light emitted from the light source to an observer's eye and transmit the illumination light reflected from the observer's eye in a direction opposite to a propagation direction of the illumination light emitted from the light source; a photodetector array configured to detect the illumination light reflected from the observer's eye; and a signal processor configured to determine an angle of rotation of the observer's eye based on a two-dimensional (2D) intensity distribution of the illumination light detected by the photodetector array.

First claim

What is claimed is:

1 . An eye-tracking device comprising:
a light source configured to emit an illumination light; a light guide plate configured to transmit the illumination light emitted from the light source to an observer's eye and transmit the illumination light reflected from the observer's eye in a direction opposite to a propagation direction of the illumination light emitted from the light source; a photodetector array configured to detect the illumination light reflected from the observer's eye; and a signal processor configured to determine an angle of rotation of the observer's eye based on a two-dimensional (2D) intensity distribution of the illumination light detected by the photodetector array.

2 . The eye-tracking device of claim 1 , wherein the light guide plate comprises a first input/output coupler and a second input/output coupler configured to guide the illumination light to be incident into the light guide plate, to travel inside the light guide plate, and to travel outside the light guide plate.

3 . The eye-tracking device of claim 2 , further comprising a beam splitter configured to transmit the illumination light emitted from the light source to the first input/output coupler and transmit the illumination light incident from the first input/output coupler to the photodetector array.

4 . The eye-tracking device of claim 3 , wherein the light source faces a first surface of the beam splitter, and the photodetector array faces a second surface of the beam splitter, and
wherein the first surface of the beam splitter is disposed to oppose the second surface of the beam splitter.

5 . The eye-tracking device of claim 3 , wherein the beam splitter comprises a half mirror configured to reflect a first half of the illumination light and transmit a second half of the illumination light.

6 . The eye-tracking device of claim 3 , wherein the beam splitter comprises a polarizing beam splitter configured to reflect the illumination light having a first linear polarization component and configured to transmit the illumination light having a second linear polarization component perpendicular to the first linear polarization component.

7 . The eye-tracking device of claim 4 , further comprising a quarter-wave plate disposed between the beam splitter and the light guide plate.

8 . The eye-tracking device of claim 3 , further comprising a varifocal lens disposed between the beam splitter and the light guide plate and configured to change a focal length according to a distance between the second input/output coupler and the observer's eye.

9 . The eye-tracking device of claim 2 , wherein the light guide plate comprises a first surface and a second surface facing the first surface,
wherein the light source and the photodetector array face the first surface of the light guide plate, and the first input/output coupler and the second input/output coupler are disposed on the second surface of the light guide plate.

10 . The eye-tracking device of claim 2 , wherein the light guide plate comprises a first surface and a second surface facing the first surface,
wherein the light source and the photodetector array face the first surface of the light guide plate, and the first input/output coupler and the second input/output coupler are disposed on the first surface of the light guide plate.

11 . The eye-tracking device of claim 2 , wherein the second input/output coupler comprises a holographic optical element having a positive refractive power to focus the illumination light, which is output from the light guide plate and passes through a pupil of the observer's eye, on a center of the observer's eye.

12 . The eye-tracking device of claim 1 , wherein the light source comprises an infrared light source configured to emit an infrared light as the illumination light.

13 . The eye-tracking device of claim 1 , wherein the photodetector array comprises a plurality of infrared detectors that are arranged in a two-dimensional (2D) manner.

14 . The eye-tracking device of claim 1 , wherein the light guide plate has a curved shape.

15 . A display apparatus comprising:
an image forming device configured to form an image; an eye-tracking device configured to track an observer's eye and comprising:
an infrared light source configured to emit an infrared illumination light;
a photodetector array comprising a plurality of infrared detectors that are arranged in a two-dimensional (2D) manner;
a light guide plate configured to transmit the infrared illumination light emitted from the infrared light source to the observer's eye and transmit the infrared illumination light reflected from the observer's eye to the photodetector array; and
a signal processor configured to determine an angle of rotation of the observer's eye based on a 2D intensity distribution of the infrared illumination light detected by the photodetector array; and
an image shifter configured to move the image according to the angle of rotation of the observer's eye.

16 . The display apparatus of claim 15 , wherein the image forming device comprises:
a visible light source configured to emit a visible light; and a spatial light modulator configured to modulate the visual light emitted from the visible light source and generate the image.

17 . The display apparatus of claim 16 , wherein the light guide plate comprises:
a first input/output coupler and a second input/output coupler configured to guide the infrared illumination light to be incident into the light guide plate, to travel inside the light guide plate, and to travel outside the light guide plate; an input coupler configured to guide the visible light into the light guide plate; and an output coupler configured to output the visible light traveling inside the light guide plate to an outside of the light guide plate.

18 . The display apparatus of claim 17 , wherein the light guide plate comprises a first surface and a second surface facing the first surface,
wherein the input coupler and the output coupler are disposed on the first surface of the light guide plate, and the first input/output coupler is disposed on the second surface of the light guide plate to face the input coupler, and the second input/output coupler is disposed on the second surface of the light guide plate to face the output coupler.

19 . The display apparatus of claim 18 , further comprising a wavelength selective mirror facing the input coupler and the first input/output coupler and configured to combine the infrared illumination light emitted from the infrared light source with the image formed by the image forming device and cause a combination of the infrared illumination light and the image to propagate through a same optical path.

20 . The display apparatus of claim 19 , further comprising a beam splitter disposed between the wavelength selective mirror and the light guide plate and configured to transmit the infrared illumination light emitted from the infrared light source to the first input/output coupler and transmit the infrared illumination light received from the first input/output coupler to the photodetector array.

21 . The display apparatus of claim 20 , wherein the infrared light source faces a first surface of the beam splitter and the photodetector array faces a second surface of the beam splitter.

22 . The display apparatus of claim 20 , wherein the beam splitter is configured to reflect a first half of the infrared i

Assignees

• Samsung Electronics Co Ltd

Inventors

• Morozov Aleksander V
• Malinovskaya Elena G
• Dubynin Sergey E
• Druzhin Vladislav V

Classifications

• G09G2360/145

  the light originating from the display screen · CPC title

• G09G3/20

  for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix {no fixed position being assigned to or needed to be assigned to the individual characters or partial characters} · CPC title

• G06F3/0304

  Detection arrangements using opto-electronic means (constructional details of pointing devices not related to the detection arrangement using opto-electronic means G06F3/033; optical digitisers G06F3/042) · CPC title

• G02B6/34

  utilising prism or grating {(G02B6/293 takes precedence)} · CPC title

• G02B2027/014

  comprising information/image processing systems · CPC title