| 摘要 |
PURPOSE:To eliminate contrast change, coloring phenomenon. or inversion phenomenon generated depending on the visual angle of a display image by inclining the direction of the main refractive index of a refractive index ellipsoid against the normal direction of a surface. CONSTITUTION:The material of a phase difference plate 1 provided with the optical anisotropy of rolled high molecular compound is formed in plate shape of thickness (d). When rectangular coordinate (x), (y), and (z) setting its surface as an x-y plane is defined, the direction of the minimum main refractive index na out of the three refractive indexes na, nb, and nc of the refractive index ellipsoid is set in parallel with the direction of y-axis, and the direction of the main refractive index nb is comprised by inclining again the normal direction of the surface in the direction of arrowhead 20 at an angle theta around the y-axis. In such a way, it is possible to convert light to linearly polarized light extending over a wide range of diopter by compensating the change of phase difference between ordinary ray and extraordinary ray corresponding to the visual angle by interposing the phase difference plate 1 whose direction of main refractive index is inclined against the normal direction. |
