Computer-generated holograms: application to intensity variable and wavelength demultiplexing holograms.

We report two kinds of Fresnel-type computer-generated hologram, namely, an intensity variable hologram and a wavelength demultiplexing hologram. The former shows that diffraction intensity can be controlled almost independently by the spatial frequencies of the holograms. The latter shows wavelength demultiplexing holograms. Combining the former intensity-controlled holograms, uniform diffraction intensity of different wavelengths can be realized.