| 摘要 |
PROBLEM TO BE SOLVED: To obtain a zoom lens which has a simple configuration most suitable for lens shutter cameras or the like and is compact though having a high variable magnification. SOLUTION: Th zoom lens includes a first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power, and a fourth lens group having a positive refracting power, in order from the object side to the image side and has at least the first, third, and fourth lens groups of these lens groups monotonously moved on an optical axis toward the object side so that an interval between the first and second lens groups is larger and an interval between the second and third lens groups is smaller in a wide angle end in comparison with those in a telephoto end. The zoom lens satisfies conditions of 4.0<f1/fw<7.0 and 2.0<f3/fw<5.0, wherein fi is a focal length of the i-th lens group when i is the number of order from the object side toward the image side, and fw is a focal length of an entire lens system in the wide angle end. COPYRIGHT: (C)2007,JPO&INPIT |
