OPTICAL IDENTIFIER COMPRISING AN IDENTIFICATION LAYER AND A SENSOR LAYER

摘要

The present invention relates to a display device with a birefringent lens system having cylindrical lenses, extending in a main direction. The polarisation of light modulated by a LC layer is twisted by a rotator layer (25') in order to be perpendicular or parallel with this main direction. A birefringent compensation layer (26) is used to remove any ellipticity introduced by the rotator layer (25'). This provides improved contrast when the display device is used e.g. in a switchable 2D/3D display.