Patent ID: 9229430
Filing Date: 2016-01-05
CPC Classification: G03H,G11B

Claim Text:
1. A device for recording a holographic 3D image, comprising: a laser generation unit for emitting a laser beam; a beam splitter unit configured to receive the laser beam from the laser generation unit and split the laser beam into a reference beam and an object beam directed to an object to be photographed; a photorefractive crystal configured to receive the reference beam from the beam splitter unit and the object beam diffused from the object to form the holographic 3D image; a rotation unit configured to rotate the photorefractive crystal once every time one holographic 3D image is recorded; and a light spot control unit disposed in light paths of the object beam between the beam splitter unit and the photorefractive crystal and configured to adjust a size of a light spot formed on the photorefractive crystal by the object beam, wherein the light spot control unit comprises a large aperture lens and a small aperture lens having an aperture less than that of the large aperture lens, a focus of the large aperture lens and a focus of the small aperture lens are coincided with each other, the object beam diffused by the object is converged to the coincided focus by the large aperture lens, and formed as a narrow parallel beam, which is illuminated on the photorefractive crystal, by the small aperture lens.