Distributed light manipulation over imaging waveguide

Abstract

In a stacked waveguide assembly, the waveguides can comprise color filters, distributed filters, and/or switch materials. Examples of color filters include dyes, tints, or stains. Examples of distributed filters and/or switch materials include dichroic filters, Bragg gratings, electronically switchable glass, and electronically switchable mirrors. Switch materials can be designed or tuned to attenuate light of unwanted colors or wavelengths. The waveguides may each be associated with a particular design wavelength. This can mean that a waveguide that is associated with a design wavelength includes an incoupling optical element is configured to deflect light at the design wavelength to an associated light distributing element and that the associated wavelength selective region is configured to attenuate light not at the design wavelength.

What is claimed is: 
     
         1 . A waveguide comprising:
 an incoupling optical element configured to couple light into the waveguide, the light comprising a first wavelength and a second wavelength not equal to the first wavelength;   a light distributing element configured to receive light from the incoupling optical element and to propagate light via total internal reflection, the light distributing element comprising a wavelength selective region configured to attenuate incoupled light at the second wavelength relative to incoupled light at the first wavelength; and   an outcoupling optical element configured to receive light from the light distributing element and to couple light at the first wavelength out of the waveguide.   
     
     
         2 . The waveguide of  claim 1 , wherein the incoupling optical element comprises a grating. 
     
     
         3 . The waveguide of  claim 1 , wherein the wavelength selective region comprises a dye, a tint, a stain, a dichroic filter, or a Bragg grating. 
     
     
         4 . The waveguide of  claim 1 , wherein the incoupling optical element does not comprise a wavelength selective filter. 
     
     
         5 . The waveguide of  claim 1 , wherein the outcoupling optical element does not comprise a wavelength selective filter. 
     
     
         6 . The waveguide of  claim 1 , wherein the wavelength selective region comprises an electronically switchable region. 
     
     
         7 . The waveguide of  claim 6 , further comprising a controller configured to switch the electronically switchable region between an on state and an off state. 
     
     
         8 . The waveguide of  claim 1 , wherein the wavelength selective region comprises a polymer dispersed liquid crystal grating. 
     
     
         9 . The waveguide of  claim 1 , wherein the light distributing element comprises a diffractive optical element. 
     
     
         10 . The waveguide of  claim 9 , wherein the diffractive optical element comprises a grating, a hologram, or a switchable diffractive optical element.