Patent ID: 8373914

Claim:
A computer generated hologram which forms a light intensity distribution on a predetermined plane by giving a phase distribution to a wavefront of incident light, said hologram comprising: a plurality of anisotropic cells each including an anisotropic medium configured to change a polarization state of the incident light; and a plurality of isotropic cells each including an isotropic medium configured not to change a polarization state of the incident light, wherein a linearly polarized light component, in a first direction, of the incident light forms a first light intensity distribution on the predetermined plane, a linearly polarized light component, in a second direction perpendicular to the first direction, of the incident light forms a second light intensity distribution different from the first light intensity distribution on the predetermined plane, and dimensions and arrangements of said plurality of anisotropic cells and said plurality of isotropic cells are set such that the linearly polarized light component in the first direction is in phase with or π out of phase from the linearly polarized light component in the second direction in a region in which the first light intensity distribution and the second light intensity distribution are superposed on each other.