Ultracompact RGB laser diode module for near-to-eye displays

We demonstrate a miniaturized, full-color RGB light source module for near-to-eye display systems, incorporating three semiconductor laser diodes (LDs) that are integrated on a free-space, micro-optical bench together with collimation optics and wavelength filters. The ultra-compact package has a footprint of 4.4 mm x 4.15 mm with a height of 2.9 mm (0.053 cm3) and an optical output window for the collimated and collinearly aligned RGB beams. The light source module delivers up to 10 mW per color at low power dissipation values of 640 mW and provides low-divergent output beams having a high circularity and a diameter of 250-650 μm at a reference distance of 50 mm.