Patent 8472119 was granted and assigned to Google on June, 2013 by the United States Patent and Trademark Office.
An optical apparatus having a waveguide that includes a bend, a first segment and a second segment operatively coupled at the bend, the first and second segments each including a pair of reflective surfaces being substantially parallel and opposing each other. An in-coupling region receives light into the first segment of the waveguide, and an out-coupling region allows the light to exit the second segment of the waveguide. A light filtering region disposed near the bend between the first segment of the waveguide and the second segment of the waveguide will selectively filter light transmitted from the first segment of the waveguide to the second segment of the waveguide.