CAMERA WITH REAL IMAGE TYPE VARIABLE MAGNIFICATION FINDER, AND PERSONAL DIGITAL ASSISTANT

摘要

PROBLEM TO BE SOLVED: To provide a real image type variable magnification finder that has sufficient high performance even at wide field angle such as a half field angle of 35°or more, and is small in size. SOLUTION: The real image type variable magnification finder includes, in order from the object side, an objective lens system having positive refractive power as a whole, and an eyepiece system having positive refractive power as a whole. The objective lens group has, in order from the object side, the first group I having negative refractive power, the second group II having positive refractive power, the third group III having negative refractive power, and the fourth group IV having positive refractive power. For zooming from a wide angle end to the telephoto end, at least the second and third groups II and III are simply moved to the object side so that a spatial interval between the second and third groups is narrowed, thereby changing the spatial intervals between the groups. If the curvature radius of the face of the second group, which face is closest to the eyepiece, is represented by r2e, and a half field angle at the wide angle end is represented byθw, the following condition (1) is satisfied: (1) -4.5