OPTICAL FILM Russian patent published in 2007 - IPC G02F1/13 

FIELD: optics.

SUBSTANCE: optical film includes array of elements and external cover, made of optical transparent material. Each element consists of at least one truncated pyramid and one non-truncated pyramid, positioned one above another so that base of the lowest truncated pyramid serves as base of the element, and upper cut of each truncated pyramid serves as base for higher pyramid, and the highest pyramid is made non-truncated. In each element corners at vortices of at least two pyramids are not equal to each other, also bases of elements are adjacent, forming a surface, while all elements are positioned on one side of given surface. External material covers sides of pyramids, while refraction coefficient of material of each pyramid is less than refraction coefficient of external material.

EFFECT: improved reflecting capacity of film.

10 cl, 6 dwg