An illumination system comprising a reflector, a cholesteric filter and a depolarizer. The cholesteric filter is arranged between a radiation source and, in a display device, a display panel, and is selected to transmit radiation having a selected state of polarization in a selected wavelength range,...http://www.google.es/patents/US5721603?utm_source=gb-gplus-sharePatente US5721603 - Illumination system and display device including such a system
Illumination system and display device including such a system
