| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a zoom lens that is small in size and has a high zooming function and excellent imaging quality, and to provide an image forming apparatus. <P>SOLUTION: The zoom lens according to the invention includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power, which are arranged in order from the object side to the image side, and satisfies the following condition: 0.15<¾L3¾/Lt<0.25, where L3 is the vector of the shift of the third lens group on the optical axis during zooming of the zoom lens from the wide angle end to the telephoto end, and Lt is the distance from the surface of the first lens facing the object to the image plane in the state in which the zoom lens is set to the telephoto end. The invention also relates to an image forming apparatus having the zoom lens. <P>COPYRIGHT: (C)2013,JPO&INPIT |
