Patent ID: 8711466
Filing Date: 2014-04-29
Classification: G02B,G03H

Abstract:
1. Illumination unit comprising a substantially planar light waveguide and at least one light source device for illuminating a controllable spatial light modulator, wherein the light waveguide comprises a planar light conducting core and a planar cladding, wherein the light modulator comprises a pixel matrix, wherein the light source device is arranged on the side of the light waveguide and wherein the light emanating from at least one light source of the light source device propagates areally though the planar light waveguide, wherein the planar light waveguide comprises on top of the cladding a planar deflection layer with a predefined output coupling characteristic for areally output coupling and deflecting an evanescent wave field of the light which propagates in the light waveguide such that a defined emission angle for homogeneously illuminating the controllable spatial light modulator is achieved, wherein the cladding is made such that its thickness tapers down in a direction of light propagation or wherein the cladding comprises a constant thickness.