| 摘要 |
A super wide-angle variable magnification viewfinder includes an objective lens group of a positive refractive power. The objective lens group further includes a fixed first lens unit of a negative refractive power, a movable second lens unit of a negative refractive power for compensating the change of a view angle, a movable third lens unit of a positive refractive power for changing the magnification of the optical system, and a fixed fourth lens unit of a positive refractive power. Also included in the finder is a prism for erecting an image and an eyepiece lens group of a positive refractive power. The objective lens group forms an actual image of an object, and the actual image can be observed through the eyepiece lens group. The view finder satisfies the condition:1.75<Lt/fT<1.87 where fT is the focal length of the objective lens group at the telephoto position, and Lt is the distance from a first lens surface of the objective lens group to a focus.
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