High-étendue multilevel surface-relief computer-generated hologram printing

This paper proposes a method that prints large multilevel computer-generated holograms (CGHs) with submicrometer-scale structures on silicon wafer surfaces using laser lithography and reactive ion etching. The resulting CGHs, featuring surface-relief structures, reconstruct three-dimensional images by modulating the phase of irradiated light. The step depth of the surface is optimized by a pre-created tone curve that corrects the exposure. We measured the shape of the surface structures and evaluated the optical properties in terms of diffraction efficiency and conjugate image generation, demonstrating high fabrication accuracy. This method enables observers to view and evaluate the optically reconstructed image of high-étendue multilevel CGHs.