COMPUTER GENERATED HOLOGRAM OPTICAL ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide a computer generated hologram optical element whose image transfer function is not lowered even if oil, water or the like is stuck on the surface. SOLUTION: The computer generated hologram optical element comprizes: a substrate; a transmission type Fourier transformation hologram comprising an image transfer layer which is formed on the substrate and has a function as a Fourier transformation lens; a diffraction function layer which is arranged on the image transfer layer of the transmission type Fourier transformation hologram and has a certain diffraction index difference between the image transfer layer and itself; and a protective layer formed on the diffraction function layer. COPYRIGHT: (C)2007,JPO&INPIT