VARIABLE POWER OPTICAL SYSTEM PROVIDED WITH VIBRATION PROOF FUNCTION

摘要

PROBLEM TO BE SOLVED: To reduce the eccentricity generation amount of a lens group while miniaturizing a device and simplifying a mechanism or the like, by moving a 32nd group in the vertical direction to an optical axis, correcting the shake of photographing images when a variable power optical system is vibrated and making the focus distances of the 32nd group and a third group and the focus distance of the entire system satisfy specified conditions. SOLUTION: This system is provided with the first group L1 of positive refractive power, the second group L2 of negative refractive power provided with a variable power function, the third group L3 of the positive refractive power and the forth group L4 of the positive refractive power provided with a correction function for correcting an image surface fluctuated by variable power and a focusing function. The third group L3 is provided with the 31st group L31 of the negative refractive power and the 32nd group L32 of the positive refractive power. Then, the 32nd group L32 is moved in the vertical direction to the optical axis, the shake of the photographing images when this variable power optical system is vibrated is corrected, and at the time of defining the focus distances of the 32nd group L32 and the third group L3 respectively as f32 and f3 and the focus distance of the wide angle end of the entire system as fW, 8