Systems, devices, and methods that integrate eye tracking and scanning laser projection in wearable heads-up displays

Patent metadata

Field	Value
Publication number	US-10429655-B2
Application number	US-201816126555-A
Country	US
Kind code	B2
Filing date	Sep 10, 2018
Priority date	May 28, 2015
Publication date	Oct 1, 2019
Grant date	Oct 1, 2019

Abstract

Systems, devices, and methods that integrate eye tracking capability into scanning laser projector (“SLP”)-based wearable heads-up displays are described. At least one narrow waveband laser diode is used in an SLP to define one or more portion(s) of a visible image. At least one corresponding narrow waveband photodetector is aligned to detect reflections of the portion(s) of the image from features of the eye. A holographic optical element (“HOE”) may be used to combine the image and environmental light into the user's “field of view.” Three narrow waveband photodetectors each responsive to a respective one of three narrow wavebands output by the RGB laser diodes of an RGB SLP are aligned to detect reflections of a projected RGB image from features of the eye.

First claim

The invention claimed is:

1. A wearable heads-up display (“WHUD”) comprising:
a first visible light source to output a first visible light in a first narrow waveband, the first visible light representative of at least a first portion of a displayed image;
a second visible light source to output a second visible light in a second narrow waveband different from the first narrow waveband, the second visible light representative of at least a second portion of a displayed image;
a transparent combiner aligned to receive the first visible light from the first light source and the second visible light from the second visible light source and to redirect both the first visible light and the second visible light towards at least one eye of a user;
a first narrow waveband detector aligned to receive at least a portion of the first visible light reflected from the at least one eye of the user, wherein the first narrow waveband detector is responsive to the first visible light in the first narrow waveband and unresponsive to light that is outside of the first narrow waveband; and
a second narrow waveband detector aligned to receive at least a portion of the second visible light reflected from the at least one eye of the user, wherein the second narrow waveband detector is responsive to the second visible light in the second narrow waveband and unresponsive to light that is outside of the second narrow waveband.

2. The WHUD of claim 1 wherein:
the transparent combiner is oriented to converge the first visible light in the first narrow waveband towards a first exit pupil at the at least one eye of the user; and
the transparent combiner is oriented to converge the second visible light in the second narrow waveband towards a first exit pupil at the at least one eye of the user.

3. The WHUD of claim 1 , further comprising a support frame which carries the first visible light source, the second visible light source, the transparent combiner, the first narrow waveband detector, and the second narrow waveband detector, wherein the support structure has a general shape and appearance of eyeglasses.

4. The WHUD of claim 1 , further comprising:
a third visible light source to output a third visible light in a third narrow waveband different from the first narrow waveband and the second narrow waveband, the third visible light representative of at least a third portion of a displayed image, wherein the transparent combiner is aligned to receive the third visible light from the third visible light source and to redirect the third visible light towards the at least one eye of the user; and
a third narrow waveband detector aligned to receive at least a portion of the third visible light reflected from the at least one eye of the user, wherein the third narrow waveband detector is responsive to the third visible light in the third narrow waveband and unresponsive to light that is outside of the third narrow waveband.

5. The WHUD of claim 4 wherein:
the first visible light source is a red light source and the first narrow waveband corresponds to a first range of wavelengths that are visible as red to the eye of the user;
the second visible light source is a green light source and the second narrow waveband corresponds to a second range of wavelengths that are visible as green to the eye of the user; and
the third visible light source is a blue light source and the third narrow waveband corresponds to a third range of wavelengths that are visible as blue to the eye of the user.

6. The WHUD of claim 4 wherein:
the first visible light source is a red laser diode and the first narrow waveband corresponds to a first range of wavelengths that are visible as red to the eye of the user;
the second visible light source is a green laser diode and the second narrow waveband corresponds to a second range of wavelengths that are visible as green to the eye of the user; and
the third visible light source is a blue laser diode and the third narrow waveband corresponds to a third range of wavelengths that are visible as blue to the eye of the user.

7. The WHUD of claim 1 wherein the transparent combiner comprises a holographic optical element (“HOE”) aligned to receive the first visible light from the first visible light source and the second visible light from the second visible light source and to redirect the first visible light and the second visible light towards the at least one eye of the user, the HOE including:
a first hologram that is responsive to the first visible laser light in the first narrow waveband and unresponsive to light that is outside of the first narrow waveband; and
a second hologram that is responsive to the second visible light in the second narrow waveband and unresponsive to light that is outside of the second narrow waveband.

8. The WHUD of claim 7 wherein the first hologram is oriented to converge the first visible light in the first narrow waveband to a first exit pupil at the at least one eye of the user and the second hologram is oriented to converge the second visible light in the second narrow waveband to the first exit pupil at the at least one eye of the user.

9. The WHUD of claim 1 , further comprising a scan mirror aligned to receive the first visible light and the second visible light and to controllably reflect the first visible light and the second visible light towards the transparent combiner.

10. A method of projecting an image to an eye of a user and tracking the eye of the user, the method comprising:
outputting, by a first visible light source, a first visible light in a first narrow waveband, the first visible light representative of at least a first portion of a displayed image;
outputting, by a second visible light source, a second visible light in a second narrow waveband different from the first narrow waveband, the second visible light representative of at least a second portion of a displayed image;
receiving, by a transparent combiner, first visible light from the first light source and the second visible light from the second visible light source;
redirecting, by the transparent combiner, both the first visible light and the second visible light towards at least one eye of a user;
receiving, by a first narrow waveband detector, at least a portion of the first visible light reflected from the at least one eye of the user, wherein the first narrow waveband detector is responsive to the first visible light in the first narrow waveband and unresponsive to light that is outside of the first narrow waveband; and
receiving, by a second narrow waveband detector, at least a portion of the second visible light reflected from the at least one eye of the user, wherein the second narrow waveband detector is responsive to the second visible light in the second narrow waveband and unresponsive to light that is outside of the second narrow waveband.

11. The method of claim 10 wherein redirecting, by the transparent combiner, both the first visible light and the second visible light towards at least one eye of a user comprises:
converging, by the transparent combiner, the first visible light in the first narrow waveband towards a first exit pupil at the at least one eye of the user; and
converging, by the transparent combiner, second visible light in the second narrow waveband towards a first exit pupil at the at least one eye of the user.

12. The method of claim 10 , further comprising:
receiving, by a scan mirror, the first visible light and the second visible light; and
controllably reflecting, by the scan mirror, the first visible light and the second visible light towards the transparent combiner.

13. The method of cla

Assignees

• Thalmic Labs Inc
• North Inc

Inventors

• Alexander Stefan
• Chapeskie Jake
• Holland Lloyd Frederick
• Mahon Thomas

Classifications

• G02B27/0172 Primary

  characterised by optical features · CPC title

• G02B2027/015

  involving arrangement aiming to get less bulky devices · CPC title

• G02B26/0833

  the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD (G02B26/0825 takes precedence; micromechanical devices in general B81B) · CPC title

• G02B27/0176

  characterised by mechanical features · CPC title

• G02B27/017

  Head mounted · CPC title