PURPOSE: To simulate relations of an optical wave between two points by inputting the dielectric constant of a principal dielectric axis and operating a differential propagation matrix based on the dielectric constant and outputting this matrix.

CONSTITUTION: In a light propagation arithmetic device 1, the dielectric constant in the direction of the major axis, that in the direction of the minor axis, and data of the angle of incidence are inputted from an input means 2 to an operating means 3. Data of the elastic constant, the dielectric anisotropy, the refractive index of light, the refractive index anisotropy, etc., is inputted as material parameters. The cell thickness, spectral transmittances in the axis of polarization and the axis of absorption of a polarizer, the spectral distribution of a light source, etc., are inputted as design parameters. A first arithmetic processing means 31 operates the differential propagation matrix, and a second arithmetic processing means 32 operates the spectral transmittance. A third arithmetic processing means 33 operates tristimulus values of chromaticity. The spectral transmittance and tristimulus values of chromaticity operated by the means 3 are outputted to a display device or the like of an output means 4, thus simulating relations of the optical wave between two points.