| 摘要 |
PURPOSE: A wide-angle variable power finder is provided to shorten the overall length of the finder and improve aberration characteristic from a wide-angle terminal to a telephoto terminal. CONSTITUTION: A wide-angle variable power finder includes an objective lens group(I) and a prism(10). The objective lens group is composed of the first, second, third and fourth lens groups(1,2,3,4) and has positive flexibility. The first lens group has negative flexibility and is fixed. The second lens group has negative flexibility and is movable. The third lens group has positive flexibility and is movable. The fourth lens group has positive flexibility and is fixed. The prism is composed of an eye lens group having positive flexibility, moves the third lens group to vary magnification, moves the second lens group to correct a diopter variation and forms an image between the third and fourth lens groups.
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