Immersed reflective polarizer with angular confinement in selected planes of incidence

Abstract

A film construction includes a broad band reflective polarizing film that may be immersed in an ultra low refractive index medium. The reflecting polarizing film is characterized by a pass axis and a block axis, and its reflectivity for white light of the pass state polarization increases with increasing incidence angle to provide a compressed or narrowed viewing cone selectively in one plane of incidence. In some embodiments, the plane of incidence associated with the compressed viewing cone is aligned with the pass axis. In other embodiments it is aligned with the block axis.

1 . A film construction, comprising:
 a multilayer optical film configured to operate substantially as:
 a mirror for visible light incident in a first plane of incidence at oblique angles; and 
 a reflective polarizer for visible light at normal incidence, and for visible light incident in a second plane of incidence at oblique angles; and 
   an optically thick low index layer having an ultra low refractive index attached to the multilayer optical film.