Computer generated hologram, exposure apparatus, and device fabrication method

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.