Systems and methods for augmented reality

Patent metadata

Field	Value
Publication number	US-11067797-B2
Application number	US-201715479700-A
Country	US
Kind code	B2
Filing date	Apr 5, 2017
Priority date	Apr 7, 2016
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

An augmented reality system includes a light source configured to generate a virtual light beam. The system also includes a light guiding optical element having an entry portion, an exit portion, and a surface having a diverter disposed adjacent thereto. The light source and the light guiding optical element are configured such that the virtual light beam enters the light guiding optical element through the entry portion, propagates through the light guiding optical element by at least partially reflecting off of the surface, and exits the light guiding optical element through the exit portion. The light guiding optical element is transparent to a first real-world light beam. The diverter is configured to modify a light path of a second real-world light beam at the surface.

First claim

The invention claimed is:

1. An augmented reality system, comprising:
a light source configured to generate a virtual light beam; and
a planar waveguide having an entry portion, an exit portion, and a surface having a diverter disposed adjacent thereto,
wherein the planar waveguide is configured to propagate light beams that are incident on the planar waveguide at angles greater than or equal to a critical angle by total internal reflection (TIR), and allow light beams that are incident on the planar waveguide at angles less than the critical angle to pass through the light guiding optical element,
wherein the light source and the planar waveguide are configured such that the virtual light beam:
(a) enters the planar waveguide through the entry portion,
(b) propagates through the planar waveguide by TIR, and
(c) exits the planar waveguide through the exit portion,

wherein the diverter is tuned to selectively:
prevent real-world light beams that are incident on the diverter at angles greater than or equal to a predetermined angle of incidence from reaching the surface of the planar waveguide, and
allow real-world light beams that are incident on the diverter at angles less than the angle of incidence to pass through the diverter to the surface of the planar waveguide, such that artifacts from real world objects at respective high angles of incidence relative to the diverter are reduced, and

wherein tuning the diverter comprises selecting a physical dimension and a chemical makeup of the diverter.

2. The system of claim 1 , wherein the diverter is configured to reflect the real-world light beams that are incident on the diverter at angles greater than or equal to the angle of incidence to prevent said real-world light beams from entering said planar waveguide through the surface of the planar waveguide.

3. The system of claim 1 , wherein the diverter is further configured to refract or diffract further real-world light beams.

4. The system of claim 1 , wherein the diverter is wavelength selective.

5. The system of claim 4 , wherein the light source is configured such that the virtual light beam has a wavelength corresponding to a wavelength for which the diverter is at least partially reflective.

6. The system of claim 1 , wherein the diverter is polarization selective.

7. The system of claim 6 , wherein the virtual light beam has a polarization corresponding to a polarization for which the diverter is reflective.

8. The system of claim 1 , wherein the diverter is configured to reduce a critical angle of the surface of the planar waveguide compared to the surface of the planar waveguide without the diverter.

9. The system of claim 1 , the planar waveguide also having a second surface, wherein the light source and the planar waveguide are configured such that the virtual light beam propagates through the planar waveguide by at least partially reflecting off of the surface of the planar waveguide and the second surface of the planar waveguide.

10. The system of claim 9 , the planar waveguide also having a second diverter disposed adjacent the second surface, wherein the second diverter is configured to selectively:
prevent real-world light beams that are incident on the diverter at angles greater than or equal to the angle of incidence from reaching the second surface of the planar waveguide, and
allow real-world light beams that are incident on the diverter at angles less than the angle of incidence to pass through the second diverter to the second surface of the planar waveguide.

11. The system of claim 1 , wherein the diverter is a coating.

12. The system of claim 11 , wherein the coating is a selectively reflective coating.

13. The system of claim 1 , wherein the diverter is a dynamic coating comprising a liquid crystal or lithium niobate.

14. The system of claim 1 , wherein the diverter comprises a metasurface material.

15. The system of claim 1 , wherein the diverter is a waveguide outcoupler.

16. The system of claim 1 , wherein the diverter includes a plurality of thin layers having different reflectance characteristics.

17. The system of claim 16 , further comprising an in-coupling grating and orthogonal pupil expander.

18. An augmented reality system, comprising:
a light source configured to generate a virtual light beam; and
a planar waveguide having an entry portion, an exit portion, and a surface having a diverter disposed adjacent thereto,
wherein the planar waveguide is configured to propagate light beams that are incident on the planar waveguide at angles greater than or equal to a critical angle by total internal reflection (TIR), and allow light beams that are incident on the planar waveguide at angles less than the critical angle to pass through the light guiding optical element,
wherein the light source and the planar waveguide are configured such that the virtual light beam:
(a) enters the planar waveguide through the entry portion,
(b) propagates through the planar waveguide by TIR, and
(c) exits the planar waveguide through the exit portion,

wherein the diverter is tuned to selectively:
prevent real-world light beams that are incident on the diverter at angles greater than or equal to a predetermined angle of incidence from reaching the surface of the planar waveguide, and
allow real-world light beams that are incident on the diverter at angles less than the angle of incidence to pass through the diverter to the surface of the planar waveguide, such that artifacts from real world objects at respective high angles of incidence relative to the diverter are reduced,

wherein the diverter is a thin film dichroic diverter, and
wherein tuning the diverter comprises selecting a physical dimension and a chemical makeup of the diverter.

19. An augmented reality system, comprising:
a light source configured to generate a virtual light beam; and
a planar waveguide having an entry portion, an exit portion, a first surface, and a second surface,
wherein the first surface of the planar waveguide has a first diverter disposed adjacent thereto,
wherein the second surface of the planar waveguide has a second diverter disposed adjacent thereto,
wherein the planar waveguide is configured to propagate light beams that are incident on the planar waveguide at angles greater than or equal to a critical angle by total internal reflection (TIR), and allow light beams that are incident on the planar waveguide at angles less than the critical angle to pass through the light guiding optical element,
wherein the light source and the planar waveguide are configured such that the virtual light beam:
(a) enters the planar waveguide through the entry portion,
(b) propagates through the planar waveguide by TIR, and
(c) exits the planar waveguide through the exit portion,

wherein the first and second diverters are each tuned to selectively:
prevent real-world light beams that are incident on the diverter at angles greater than or equal to a predetermined angle of incidence from reaching the respective first and second surfaces of the planar waveguide, and
allow real-world light beams that are incident on the diverter at angles less than the angle of incidence to pass through the respective first and second surfaces of the planar waveguide, such that artifacts from real world objects at respective high angles of incidence relative to the diverter are reduced, and

wherein tuning the diverter comprises selecting a physical dimension and a chemical makeup of the diverter.

20. The sys

Assignees

• Magic Leap Inc

Inventors

• Schowengerdt Brian T
• Watson Mathew D

Classifications

• G02B30/52

  the three-dimensional [3D] volume being constructed from a stack or sequence of two-dimensional [2D] planes, e.g. depth sampling systems · CPC title

• G02B27/0103

  comprising holographic elements · CPC title

• G02B2027/0194

  with combiner of laminated type, for optical or mechanical aspects · CPC title

• G02B27/0101 Primary

  characterised by optical features (G02B27/0172 takes precedence) · CPC title

• G02B2027/012

  comprising devices for attenuating parasitic image effects · CPC title