Array projection optics. Multi-channel design for ultra slim projectors

Common projection optics use a single aperture approach to create a magnified image on a screen. The transmitted flux of such systems always scales with their system dimensions thus preventing the realization of ultra compact devices along with a high lumen output. We introduce a new multi-channel approach that breaks this rule and enables the realization of ultra slim, laterally extended projection devices with high flux and integrated homogenization. Array projection optics consists of a regular two-dimensional arrangement of projective microlenses superposing their images on the screen. First we derive the scaling laws of such a multi-channel projector in contrast to common single aperture optics and analyze the system parameters of a single projection channel by Seidel aberration theory. Based on the application of these results to a variable array size the array projection optics are specified. The technological realization of a sample system with still image projection is shown and characterized with respect to modulation transfer and flux.