| 摘要 |
PURPOSE:To easily form a liquid crystal cell, and to obtain a cylindrical lens having a variable focal distance, by providing a pair of linear electrodes on the columnar cell of a plate. CONSTITUTION:In a liquid crystal cell 40 having a rectangular section, which is constituted of two pieces of transparent plates 41, 42 and side plates 43, 44, etc., a liquid crystal is enclosed in its inside. In the vicinity of the lower part of the inside of the cell of the side plates 43, 44, linear electrodes 45, 46 are provided in the direction vertical to the paper surface, by which a liquid crystal cell is constituted. When an AC voltage from an external driving power source 47 is applied to one end of said linear electrodes 45, 46, since an electric line of force is generated in the liquid crystal in the liquid crystal cell 40, a liquid crystal molecule in the cell 40 is oriented so as to be arranged in order along this electric line of force. Accordingly, a refractive index distribution is generated in the inside of the liquid crystal cell 40. In this way, in the peripheral edge part and the center part of the liquid crystal cell, the refractive indexes are different from each other, therefore, an action as a cylindrical lens is executed. |
