Dual-sided film with compound prisms

摘要

Dual-sided optical films have extended prisms formed in one major surface, and extended lenslets formed in an opposite major surface. Some or all of the prisms are compound prisms, in which the two inclined surfaces of each compound prism each include a tip portion, a base portion, and an intermediate portion disposed between the tip portion and the base portion, the intermediate and tip portions forming a concave shape and the intermediate and base portions forming a convex shape, or vice versa. When obliquely incident light, e.g. from a light guide, is incident on the prism side of the film, an output beam emerges from the lenslet side of the film. The output beam has an intensity distribution with a sharp left beam edge and a sharp right beam edge, these beam edges having 10%-to-90% transition angles of no more than 7, 6, 5, 4, 3, or 2 degrees.

主权项

1. An optical film having opposed first and second structured surfaces, the optical film comprising:
a plurality of extended prisms formed in the first structured surface; a plurality of extended lenslets formed in the second structured surface; and wherein the prisms and lenslets are arranged in a one-to-one correspondence of lenslets to prisms; and wherein at least some of the prisms are compound prisms, each compound prism having two inclined surfaces that are compound and a sharp vertex, each such compound inclined surface of each compound prism having a tip portion, a base portion, and an intermediate portion disposed between the tip portion and the base portion, the intermediate portion forming a first profile shape with the tip portion and a second profile shape with the base portion, and wherein the first profile shape is concave and the second profile shape is convex, or the first profile shape is convex and the second profile shape is concave.