Hybrid coupling diffractive optical element

Patent metadata

Field	Value
Publication number	US-11675192-B2
Application number	US-202016800886-A
Country	US
Kind code	B2
Filing date	Feb 25, 2020
Priority date	Dec 6, 2019
Publication date	Jun 13, 2023
Grant date	Jun 13, 2023

Abstract

A multi-functional diffractive optical element (DOE) for redirecting light into a waveguide and providing higher order aberration correction is described. The multi-functional DOE may be positioned on, connected to, adjacent to, or within a waveguide, and in some examples is positioned at, or near, the exit pupil of the projector lens. In an example, a head-mounted display (HMD) is configured to output artificial reality content, comprising a waveguide configured to receive input light and configured to output the received input light to an eyebox. The HMD further comprises a projector configured to input light into the waveguide, the projector comprising a display, a projection lens, and a multi-functional diffractive optical element (DOE) configured to redirect light from the projector into the waveguide and provide higher order aberration correction of the light from the display.

First claim

What is claimed is:

1. A head-mounted display (HMD) configured to output artificial reality content, comprising:
a waveguide configured to receive input light and configured to output the received input light to an eyebox;
a projector configured to input light into the waveguide, the projector comprising:
a display;
a projection lens; and
a multi-functional diffractive optical element (DOE) configured to redirect light from the projector into the waveguide,
wherein a length of the projector along its optical axis from a stop of the projection lens to the display is less than 4 mm,
wherein the stop is positioned opposite the projection lens from a focal plane of the projection lens, wherein the stop is positioned between the multi-functional DOE and the projection lens.

2. The HMD of claim 1 , wherein the multi-functional DOE includes a linear phase profile and a higher order aberration correcting phase profile.

3. The HMD of claim 2 , wherein the multi-functional DOE includes a rotationally symmetric higher order aberration correcting phase profile and a non-rotationally symmetric phase profile.

4. The HMD of claim 3 , wherein the multi-functional DOE is configured to compensate for the aberrations of the projection lens.

5. The HMD of claim 1 , wherein the multi-functional DOE is positioned to within 500 mm of a stop of the projection lens.

6. The HMD of claim 5 , wherein the multi-functional DOE is positioned adjacent to a major surface of the waveguide.

7. The HMD of claim 1 , wherein the multi-functional DOE is a transmissive DOE or a reflective DOE.

8. A projection lens comprising:
one or more lens elements having optical power and configured to collimate light emitted at or near a focal plane of the projection lens;
a multi-functional diffractive optical element (DOE) comprising:
a linear phase profile; and
a higher order aberration correcting phase profile, wherein the higher order aberration correcting phase profile is configured to provide higher order aberration correction of light incident on the multi-functional DOE; and

a lens stop positioned opposite the one or more lens elements from the focal plane and positioned between the multi-functional DOE and the one or more lens elements,
wherein a length of the projection lens along its optical axis from the lens stop of the projection lens to a display is less than 4 mm.

9. The projection lens of claim 8 , wherein the periodic phase profile is configured to redirect light incident on the multi-functional DOE into a waveguide.

10. The projection lens of claim 8 , wherein the higher order aberration correcting phase profile is configured to compensate for the aberrations of a projection lens that is configured to direct light to the multi-functional DOE.

11. The projection lens of claim 8 , wherein the higher order aberration correcting phase profile includes a rotationally symmetric higher order aberration correcting phase profile and a non-rotationally symmetric phase profile.

12. The projection lens of claim 8 , wherein the multi-functional DOE comprises a transmissive DOE.

13. The projection lens of claim 8 , wherein the multi-functional DOE comprises a reflective DOE.

14. The projection lens of claim 8 , wherein the multi-functional DOE comprises a metasurface or a metamaterial.

15. A method of projecting an image, the method comprising:
emitting light from an electronic display;
collimating the emitted light via a projection lens;
redirecting the collimated emitted light via a multi-functional DOE; and
compensating for the aberrations of the projection lens via the multi-functional DOE,
wherein a length of the projection lens along its optical axis from a stop of the projection lens to the electronic display is less than 4 mm,
wherein the stop is positioned opposite the projection lens from the electronic display, wherein the stop is positioned between the multi-functional DOE and the projection lens.

16. The method of claim 15 , wherein compensating for the aberrations of the projection lens includes inducing a rotationally symmetric phase delay profile and a non-rotationally symmetric phase delay profile to the wavefront of the collimated emitted light.

17. The method of claim 16 , wherein the redirecting the collimated emitted light comprises redirecting the collimated emitted light into a waveguide.

18. The method of claim 17 , further comprising:
positioning the multi-functional DOE at a major surface of the waveguide.

19. The method of claim 15 , further comprising:
positioning the multi-functional DOE within 500 mm from a stop of the projection lens.

20. The method of claim 15 , further comprising:
positioning the multi-functional DOE within 4 mm from the electronic display.

21. A projector lens comprising:
one or more lens elements having optical power and configured to collimate light emitted at or near a focal plane of the projector lens;
a multi-functional diffractive optical element (DOE) comprising:
a linear phase profile; and
a higher order aberration correcting phase profile configured to provide higher order aberration correction to light incident on the multi-functional DOE; and

a lens stop positioned opposite the one or more lens elements from the focal plane and positioned between the multi-functional DOE and the one or more lens elements.

Assignees

• Meta Platforms Tech Llc

Inventors

• Elazhary Tamer Mohamed Tawfik Ahmed Mohamed
• Schaub Michael Patrick
• Taylor Byron

Classifications

• G02B27/0093 Primary

  with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking · CPC title

• G02B2027/0178

  Eyeglass type (eyeglass details G02C) · CPC title

• G02B6/0016

  Grooves, prisms, gratings, scattering particles or rough surfaces · CPC title

• G02B2027/0138

  comprising image capture systems, e.g. camera · CPC title

• G02B27/0056

  by using a diffractive optical element · CPC title