Generation of a hologram pattern

Abstract

Device for generating a hologram pattern including selecting means for selecting, as cross section ranges which are in a plurality of cross sections parallel to hologram pattern in 3D object and which are ranges used for generating hologram pattern, cross section ranges which overlap ranges in other cross sections when the relevant cross section is perspectively seen from a predetermined observation point on the hologram pattern; depth integrating means for calculating, for lattice points in one cross section range, a depth integral function acquired by integrating an inverse diffraction function for determining hologram pattern for displaying points of 3D object with respect to respective lattice points in the cross section ranges which overlap the relevant lattice point; and inverse Fourier transform means for generating hologram pattern by performing two-dimensional inverse transform on depth integral functions with respect to plurality of lattice points in one cross section range.

1 . A generation device for generating a hologram pattern, comprising:
 distance information acquiring means for acquiring, for each pixel of a two-dimensional image acquired by projecting a 3D object to be displayed onto a predetermined plane, distance information representing a distance from the relevant pixel to a portion of the 3D object, the portion being recorded as the relevant pixel;   inverse diffraction function generating means for generating, for each pixel of the two-dimensional image, an inverse diffraction function for determining a hologram pattern for displaying a portion of the 3D object recorded as the relevant pixel, based on the distance information at the relevant pixel; and   inverse Fourier transform means for generating the hologram pattern by performing a two-dimensional inverse Fourier transform on the inverse diffraction functions with respect to variables representing coordinates in the two-dimensional image.   
   
   
       2 . A method of generating a hologram pattern using a computer, comprising the steps of:
 acquiring, for each pixel of a two-dimensional image acquired by projecting a 3D object to be displayed onto a predetermined plane, distance information using the computer, the distance information representing a distance from the relevant pixel to a portion of the 3D object, the portion being recorded as the relevant pixel;   generating, for each pixel of the two-dimensional image, an inverse diffraction function for determining a hologram pattern for displaying a portion of the 3D object recorded as the relevant pixel, based on the distance information at the relevant pixel using the computer; and   generating the hologram pattern using the computer, by performing a two-dimensional inverse Fourier transform on the inverse diffraction functions with respect to variables representing coordinates in the two-dimensional image.   
   
   
       3 . A computer program product comprising a computer usable medium having computer readable program code stored therein for causing generation of a hologram, the computer readable program code means in said computer program product comprising computer readable program code means for causing a computer to effect the functions of a method comprising steps of:
 acquiring, for each pixel of a two-dimensional image acquired by projecting a 3D object to be displayed onto a predetermined plane, distance information using the computer, the distance information representing a distance from the relevant pixel to a portion of the 3D object, the portion being recorded as the relevant pixel;   generating, for each pixel of the two-dimensional image, an inverse diffraction function for determining a hologram pattern for displaying a portion of the 3D object recorded as the relevant pixel, based on the distance information at the relevant pixel using the computer; and   generating the hologram pattern using the computer, by performing a two-dimensional inverse Fourier transform on the inverse diffraction functions with respect to variables representing coordinates in the two-dimensional image.