OPTICAL SYSTEM

摘要

The invention relates to an optical system (1) comprising a polarizing element (3) in the form of a layer which comprises an isotropic material having a refractive index ni and an anisotropic material having refractive indices na,e and na,o. The refractive index ni is substantially equal to na,e or na,o. The optical system comprises retroreflecting means for back-reflecting the polarization component diffused in the polarizing element (3). The invention also relates to a flat picture display device (12, 30, 60) and an image projection device (45, 53) provided with such an optical system (1).