| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to obtain good images free from unsharpness, etc., at all times by providing the device with an optical characteristic variable optical element and changing the MTF characteristic of an electronic circuit, such as aberration fluctuation, or correcting the same by changing an image processing method when the optical characteristics of the optical characteristic variable optical element are changed. SOLUTION: The variable focus lens is constituted by providing transparent substrates 4, 5 with liquid crystals 1 having negative anisotropy of a refractive index, an alignment layer 2 and transparent electrodes 3. The variable focus optical element consisting of such liquid crystals 1 having the negative anisotropy of the refractive index is n0 in the refractive index of the liquid crystals on incident light when voltage is not impressed. The optical element acts as a convex lens. When a switch 9 is turned on thereafter, the refractive index to the incident light attains n=(ne+n0)/2 and lowers, where ne is the refractive index of an extraordinary ray and n0 is the refractive index of an ordinary ray. The element acts as a variable focus lens as a result of the lowering. The change in the refractive index is made continuos by changing a variable resistor 13 and the continuous changing of the focal length of the optical element is made possible. |
