PROJECTOR OPTICS

Projector methods, devices, software are described for a high decrease of the black level without decrease or a limited decrease of the luminance of the bright pixels for use with high contrast and high dynamic range projectors, e.g. based on RGB lasers or phosphor converted lasers. Such projectors can be used in a digital cinema, in a home theatre, in virtual reality systems, in simulators for training, for example. The projector optical system is adapted to vary, according to an average picture level, an effective étendue of the light source and to keep light power confined within a varying cone angle, whereby at the imaging system the projector étendue is matched to the effective étendue of the light source, the effective light source étendue and the projector étendue being controlled to the average picture level.