| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens having high performance and high variable power rate. SOLUTION: As to this zoom optical system whose total systems are constituted of five or more lens groups G1 to G5 and whose zoom variable power part is constituted of four or more variable power lens groups G2 to G5 among the lens groups G1 to G5 ; the magnificationβc2 ,βc3 ,βc4 andβc5 of the respective lens groups G2 , G3 , G4 and G5 are nearly unmagnification in the case the magnificationβc2 ,βc3 ,βc4 andβc5 of a zoom variable power part are nearly the unmagnification.
|
