Holographic recording apparatus and holographic optical element

Claim 1

A holographic recording apparatus comprising: a means for generating a light beam and for splitting said light beam into a first light beam and a second light beam; a mask which is located in front of a hologram recording material and which has an aperture, first interference fringes being recorded in a first hologram cell on the hologram recording material corresponding to said aperture and second interference fringes being recorded in a second hologram cell on the hologram recording material corresponding to said aperture; movement means for supporting the hologram recording material masked by said mask and for relatively moving the hologram recording material with respect to the mask in predetermined directions so that an interference pattern is formed in an area on the hologram recording material, wherein said movement means includes a first movement means for moving the hologram recording material in a linear direction, and a second movement means for moving the hologram recording material in a rotational direction; spatial frequency changing means, coupled to said means for generating and splitting said light beam, for changing incident angles of at least one of the first and second light beams with respect to the mask; phase adjustment means for changing a phase of at least one of the first light beam and the second light beam; and monitor means for monitoring the first and second interference fringes, wherein the phase adjustment means: (a) changes the phase of at least one of the first light beam and the second light beam on the basis of the interference fringes monitored by said monitor means and (b) causes the phases of the first and second interference fringes in adjacent first and second hologram cells to match each other, wherein the first and second light beams are projected onto an area including at least one of a plurality of hologram cells, while said movement means moves the hologram recording material, wherein said means for generating said light beam and for splitting said light beam generates a spherical wave and an aspherical wave which correspond to said first and second light beams, respectively, and wherein said means for generating said aspherical wave which corresponds to said second light beam comprises a deformable mirror device for phase-modulating the second light beam emitted from the means for generating said light beam in a hologram cell unit, a phase-modulated light from said deformable mirror device corresponding to said aspherical wave.