Variable magnification finder

Optical: systems and elements – Compound lens system – Variable magnification

Patent

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Details

359431, G02B 2300

Patent

active

059176504

ABSTRACT:
The present invention relates to a variable magnification finder comprising an objective lens group having a positive refractive power for enabling a wide angle view of an object. The objective lens group includes a first lens sub-group having either a negative or a positive refractive power; a second lens sub-group having a negative refractive power; a third lens sub-group having a positive refractive power and having a cemented lens with at least two pieces; and a fourth lens sub-group having a positive refractive power. The third lens sub-group is movable for magnifying the image, and the second lens sub-group is movable for compensating the focus of the magnified image. The finder further comprises an eyepiece lens group having a positive refractive power for viewing the image.

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