Patent ID: 6462869
Filing Date: 2002-10-08
Classification: G02B,G03B

Abstract:
A projection screen, particularly for large-surface image projection, for representing images by back-projection, comprising a plurality of holographic-optical elements arranged in an imaging plane and respectively adapted for imaging thereon partial regions of an image to be projected, said elements being configured to have the optical properties of a diffraction grating and at least one lens, wherein each holographic-optical element is arranged to combine light bundles of different chromatic components of the to-be-projected partial region which are incident under different light entry angles, into a common exiting light bundle having a uniform light exit angle,characterized in that the holographic-optical elements respectively comprise only one diffraction grating, and that the diffraction grating is arranged to diffract the light bundles of the individual chromatic components under different diffraction angles, and each holographic-optical element comprises a screen cylinder lens including a plurality of cylinder lenses.