| 摘要 |
PURPOSE:To dissolve annoyance due to the use of a compound eye spectacles and inconvenience due to the stricture of a visual field, by providing a lens body which converts two focal points on a frame of spectacles. CONSTITUTION:The lens body 2 supported at least on one side of the frame of spectacles 1 constitutes at least one side of a substrate consisting of a liquid crystal lens in a shape of lens, and also, the refractive index of the substrate larger than that of the liquid crystal lens for an ordinary ray, and smaller than the inflective index for an extraordinary ray, is selected. The lens body 2 in which a twisted nematic liquid crystal cell 5 is interposed between a liquid crystal cell 7 forming a lens shape where a liquid crystal molecule is oriented in an appropriate direction and a polarizing plate 6 arranged on an optical axis is constituted. And a voltage value to be impressed on the nematic liquid crystal cell 5 is changed, thereby, the polarizing direction on incident light is switched, and the refractive index of the liquid crystal cell 7 is switched to two focal points in concave or convex lenswise. In such way, it is possible to obtain a liquid crystal lens type spectacles for far and near capable of using the entire plane of the lens body.
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