Patent ID: 8885997

Claim:
A method for presenting an image, comprising: (a) projecting light from a light source into an optical element, the light including at least first and second wavelength bands, and the optical element including at least first and second waveguides, the first and second waveguides each having at least one optical grating; (b) modifying, for a first time, the polarization of the second wavelength band incident on the first waveguide from a first state to a second state so that the second wavelength band predominantly does not couple within the first waveguide; (c) controlling the polarization of the first wavelength band incident on the first waveguide to be different than the polarization of the second wavelength band incident on the first waveguide so that the first wavelength band couples within the first waveguide to a greater extent than the other than first wavelength bands; and (d) modifying, for a second time, the polarization of the second wavelength band incident on the second waveguide from the second state to the first state so that the second wavelength band predominantly couples within the second waveguide.