| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high performance real image type variable power finder, with which high variable power and miniaturization, especially the reduction of a thickness are simultaneously attained. SOLUTION: In the real image type variable power finder, in which a positive objective optical system and a positive eyepiece optical system are arranged and which possesses an image inverting means to convert a real image formed by an objective optical system into an erect normal image; the objective optical system possesses a plurality of movable lens groups G2 and G3 and a rotationally asymmetrical reflection surface, in which at least one surface has power, further possesses at least one aspherical surface at each group; and satisfies the conditional expression 0.02<d.fw/ft2<0.4, where (d) stands for a distance from the first surface of the objective optical system to a first reflection surface measured along the axial principal ray, and fw stands for the focal length of the objective optical system on the wide-angle end and ft stands for the focal length of the objective optical system on the telephoto end.
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