Patent ID: 7046409

Claim:
A holographic stereogram forming apparatus comprising: a laser source for emitting a laser beam; beam separating means for separating said laser beam emitted from said laser source into a reference beam and an object beam; reference beam irradiating means for irradiating a hologram recording medium with said reference beam separated by said beam separating means; a spatial beam modulator for displaying an image and modulating said object beam separated by said beam separating means; a one-dimensional diffuser plate for diffusing said object beam modulated by said spatial beam modulator in a one-dimensional direction; and an object projection optical system including a spherical lens system for forming said image displayed by said spatial beam modulator in said one-dimensional direction and a cylindrical lens system for condensing said object beam on said hologram recording medium in a direction substantially orthogonal to said one-dimensional direction said object projection optical system being, disposed between said spatial beam modulator and said one-dimensional diffuser plate for processing said object beam modulated by said spatial beam modulator in such a manner that said image displayed by said spatial beam modulator is formed on said one-dimensional diffuser plate in the one-dimensional direction of the one-dimensional diffuser plate using the spherical lens system, a condensing position of the object beam is controlled by regulating the spacing between said spherical lens system and said cylindrical lens system, wherein a focal distance of the cylindrical lens system and a focal distance of the spherical lens system are selected such that the spatial beam modulator and the one-dimensional diffuser are located at optically conjugate positions.