Color-selective waveguides for augmented reality/mixed reality applications
Color-selective waveguides, methods for fabricating color-selective waveguides, and augmented reality (AR)/mixed reality (MR) applications including color-selective waveguides are described. The color-selective waveguides can advantageously reduce or block stray light entering a waveguide (e.g., red, green, or blue waveguide), thereby reducing or eliminating back-reflection or back-scattering into the eyepiece.
1. An optical device comprising:
a waveguide that includes one or more patterned regions and one or more unpatterned regions on one or more surfaces of the waveguide, wherein the one or more patterned regions include an incoupling grating (ICG) configured to incouple one or more of red light, green light, and blue light; and
a polymer coating on at least a portion of at least one unpatterned region of at least one surface of the waveguide, wherein the polymer coating includes a chromatic component that is configured to absorb at least 90% of one or more of red light, green light, and blue light traveling through the waveguide, wherein the at least 90% of one or more of red light, green light, and blue light is light that the ICG is not configured to incouple.
2. The optical device of claim 1 , wherein the waveguide is formed of a glass material.
3. The optical device of claim 1 , wherein the waveguide is formed of a polymer material.
4. The optical device of claim 1 , wherein the one or more patterned regions further include one or more diffractive regions.
5. The optical device of claim 4 , wherein the polymer coating is between the ICG and one of the one or more diffractive regions.
6. The optical device of claim 4 , wherein the polymer coating is around the ICG.
7. The optical device of claim 4 , wherein the polymer coating is around the ICG and around at least one of the one or more diffractive regions.
8. The optical device of claim 4 , wherein the one or more diffractive regions include one or more of an exit pupil expander (EPE) and an orthogonal pupil expander (OPE).
9. The optical device of claim 1 , wherein the polymer coating is a first polymer coating on a first surface of the waveguide, and wherein the optical device includes a second polymer coating on at least a portion of a second surface of the waveguide that is opposite to the first surface.
10. The optical device of claim 9 , wherein the second polymer coating includes the same chromatic component as the first polymer coating.
11. The optical device of claim 9 , wherein the chromatic component is a first chromatic component, and wherein the second polymer coating includes a second chromatic component that absorbs at least 90% of a different one of the one or more of red light, green light, and blue light than the first chromatic component.
12. The optical device of claim 9 , wherein the second polymer coating is on at least a portion of a second surface of the waveguide that is opposite at least one of the one or more patterned regions on the first surface of the waveguide.
13. The optical device of claim 9 , wherein the first polymer coating differs from the second polymer coating in one or more of thickness, composition, concentration, transmission, color, and color absorption.
14. The optical device of claim 9 , wherein the first polymer coating is on at least two non-contiguous regions of the first surface, and wherein the second polymer coating is contiguous on the second surface.
15. The optical device of claim 1 , wherein the polymer coating is a first polymer coating on a first surface of the waveguide, wherein the optical device includes a second polymer coating on at least a different portion of the first surface of the waveguide than the first polymer coating, wherein the chromatic component is a first chromatic component, and wherein the second polymer coating includes a second chromatic component that absorbs at least 90% of a different one of the one or more of red light, green light, and blue light than the first chromatic component.
16. The optical device of claim 1 , wherein the polymer coating has substantially a same refractive index as the waveguide.
17. The optical device of claim 1 , wherein the optical device is an eyepiece.
18. The optical device of claim 17 , wherein the polymer coating includes a first concentration of the chromatic component on a first portion of the waveguide and a second concentration of the chromatic component on a second portion of the waveguide, wherein the first concentration is lower than the second concentration, and wherein the first portion is an area of the waveguide in which interference with a user's vision would occur with the second concentration of the chromatic component and wherein the second portion is an area of the waveguide in which interference with a user's vision would not occur with the second concentration of the chromatic component.
19. The optical device of claim 2 , wherein the polymer coating is:
on a surface of the waveguide comprising the ICG; and
between the ICG and an edge of the waveguide;
and further comprising:
a second polymer coating on the surface of the waveguide comprising the ICG; and
a second patterned region on the surface of the waveguide comprising the ICG, the second patterned region comprising a diffractive pattern spaced apart from the ICG,
wherein the second polymer coating is between the ICG and the second patterned region.