Patent ID: 8072661
Filing Date: 2011-12-06
Classification: G02B,G03F,G03H

Abstract:
1. 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, comprising an anisotropic layer whose refractive index with respect to linearly polarized light in a first polarization direction is different from a refractive index of the anisotropic layer with respect to linearly polarized light in a second polarization direction perpendicular to the first polarization direction, and an isotropic layer whose refractive index with respect to the linearly polarized light in the first direction is equal to a refractive index of the isotropic layer with respect to the linearly polarized light in the second direction, wherein a first light intensity distribution formed on the predetermined plane by a linearly polarized light component in the first polarization direction of the incident light is made different from a second light intensity distribution formed on the predetermined plane by a linearly polarized light component in the second polarization direction of the incident light by giving different phase distributions to a wavefront of the linearly polarized light component in the first polarization direction of the incident light, and a wavefront of the linearly polarized light component in the second polarization direction of the incident light, wherein the computer generated hologram includes a plurality of cells, and a thickness of the anisotropic layer and a thickness of the isotropic layer are set for each of the plurality of cells, and wherein the number of thicknesses of the anisotropic layer is smaller than the number of thicknesses of the isotropic layer in the plurality of cells.