VIBRATIONSBESTÄNDIGES TELEZOOMOBJEKTIV MIT FÜNF LINSENGRUPPEN VOM HINTERFOKUS-TYP

A telephoto-type of zoom lens wherein the image plane movement upon lens shifting is minimized. From object to image, a power variation section (G1-G4) includes two lens groups movable along the optical axis and a final fixed lens group (G5) includes first to third sub groups (L51;L52,L53;L54) having negative, positive and positive refracting powers. The second sub group (L52,L53) is shiftable substantially perpendicularly to compensate for image shake. The inequality 0.2 < ft/fBt < 0.8 is satisfied where ft and fBt are the focal distances at telephoto end of the whole zoom lens and entire lens groups disposed on the object side of said third sub group (L54), respectively. With such a zoom lens, an optimum image-shift amount to image-blur ratio, ie. a lens-shift amount easy to control without increasing the size of the mechanism, can be obtained.