| 摘要 |
PROBLEM TO BE SOLVED: To enhance brightness, to obviate the occurrence of moire fringes and to enhance visibility by forming the surface part of a reflection plate to a saw tooth shape consisting of triangular shapes connected to each other and matching the pitch of these triangular shapes with the dot pitch of liquid crystal cells, thereby roughening the surface. SOLUTION: The surface part has the saw tooth shape consisting of triangular prisms continuously arranged with their ridge lines in contact with each other and the sections in the direction perpendicular to the ridge lines connected with trianglar shapes. The pitch of the triangular shapes is matched with the dot pitch of the liquid crystal cells and the surface of the reflection plate is roughened. The reflection plate has the reflected light quantity distribution characteristic different from the reflected light quantity distribution characteristic of the conventional reflection plates. The specular reflection angle of the plate is θ when the incident angle of the light to the reflection plate is defined as θ (0<θ<90 deg.). The dependence of the reflected light quantity on angles, when measured, is |θ-θ'|>=0 deg. more preferably |θ-θ'|>=5 deg. when the reflection angle at which the reflected light quantity is maximized is defined as θ'(0<θ'<90 deg.). Then, the visibility is improved. The occurrence of the moire fringes is suppressed by matching the pitch of the triangular shapes and the dot pith of the liquid crystal cells. |
