| 摘要 |
PURPOSE:To vary the degree of sharpness of an image forming state by using a double refractivity by constituting the titled filter so that a liquid crystal layer whose arrangement is varied between a homogeneous arrangement and a homeotropic arrangement by applying an electric field is combined with a transparent electrode provided with plural opening parts. CONSTITUTION:In case a switch 18 is set to an A position, a liquid crystal layer 17 attains a homogeneous arrangement in a no-electric field state, a passing light shows uniformly a double refractivity on the whole surface, passes through in a medium having a thickness (d) and a refractive index ne, and the variation of a wave surface does not occur. In case the switch 18 is set to a position of B, an electric field is applied to the liquid crystal layer through an insulating layer 16 by transparent electrodes 15, 13. In this case, the liquid crystal layer 17 between a non-opening part 23 of the transparent electrode 15 and the transparent electrode 13 attains a homeotropic arrangement, and a light passing through this part passes through a medium having a refractive index no and a thickness (d). As a result, ned and nod are obtained in an opening part 21 and a non-opening part 23, respectively, and each is different in optical path length, and in case the switch 18 is set to (c) too, it has an optical path length of ned and nod1 in an opening part 20 and a non-opening part 22, respectively, in the same way. |
