US Patent 11231568 Illumination apparatus

An illumination apparatus comprises an array of micro-LEDs, an aligned plurality of directional catadioptric optical elements, light redirecting micro-optics and a reflective polariser. The directional illumination apparatus is arranged to provide a uniform spatial distribution across its output area by recirculating reflected high luminous intensity regions into low luminous intensity regions of the catadioptric optical element. A thin and efficient illumination apparatus with high spatial uniformity may be provided for illumination in environmental lighting, display backlighting or direct display.