An optical film is provided which comprises a disperse phase of polymeric particles disposed within a continuous birefringent matrix. The film is oriented, typically by stretching, in one or more directions. The size and shape of the disperse phase particles, the volume fraction of the disperse phase,...http://www.google.de/patents/US6590705?utm_source=gb-gplus-sharePatent US6590705 - Optical film with co-continuous phases
