Patent attributes
A display includes a reflective spatial light modulator, an angularly varying diffusion film that that transmits and scatters light incident within a first angular range and transmits light un-deviated incident within a second angular range outside of the first angular range, and a frontlight including a light source positioned to emit light into a film with a light emitting region positioned between the reflective spatial light modulator and the varying angle diffusion film. In one embodiment light extracted in the light emitting region is incident on a spatial light modulating layer at an angle of peak luminous intensity less than 30 degrees in a second layer from the surface normal of the spatial light modulating layer, reflects from the reflective spatial light modulator, passes through the film, is scattered by the angularly varying diffusion film, and exits the display.