Display with a privacy viewing mode including a film-based lightguide backlight between a first backlight and a transmissive display

Abstract

In one embodiment, a display comprises a film-based lightguide backlight disposed between a first backlight and a transmissive spatial light modulator. The film-based lightguide backlight illuminates the transmissive spatial light modulator in at least one region with light with a smaller angular full-width at half-maximum luminous intensity than the light from the first backlight such that when only the film-based backlight is emitting light, the viewing angles, in at least in the horizontal light output plane, are narrow such that the view of a region of the display is a privacy view, preventing viewers outside the narrow viewing angle from seeing the privacy sub-region display.

Dependencies are inferred from the claim text.