Patent ID: 6091547
Filing Date: 2000-07-18
Classification: F21V,G02B,G02F

Abstract:
A luminance control film assembly comprising:a first luminance control film, and a second luminance control film;said first luminance control film having a first prism axis;said second luminance control film having a second prism axis;wherein, said first prism axis and said second prism axis are not parallel, thereby forming a crossing angle theta;each of said first and said second luminance control films having a body portion having a first surface and a second surface;each of said first surfaces having a linear array of prisms characterized by pitch less than 30 micrometers whereby diffractive effects will cause a soft luminance dropoff as a viewer moves off a central viewing axis;each of said second surfaces being planar;said first luminance control film stacked on said second luminance control film such that the prisms of said first surface of said first luminance control film are proximate said second surface of said second luminance control film.