1990-03-22
1991-07-02
Henry, Jon W.
350560, 350427, 350423, G02B 2314, G02B 1515, G02B 1516, G03B 1302
Patent
active
050281259
ABSTRACT:
A zoom finder of a real image type comprises an objective lens composed of a first lens group having a positive refracting power, a second lens group having a negative refracting power, and a third lens group having a positive refracting power, the objective lens having a positive refracting power as a whole; an eyepiece composed of a fourth lens group having a positive refracting power; a device for forming a real image by the objective lens between the third and fourth lens groups and observing this real image through the eyepiece; and a device for increasing the magnification of the finder by moving the second lens group from an object side to an eyepiece side. The change is diopter of the finder caused by a zooming operation in the movement of the second lens group is corrected by displacing the first and third lens groups.
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Henry Jon W.
Ricoh & Company, Ltd.
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