| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a small-sized telephoto zoom lens which has high imaging performance and achieves a high variable power ratio, and an imaging apparatus including the zoom lens.SOLUTION: The zoom lens includes at least a first lens group G1 having a positive refracting power, a second lens group G2 having a negative refracting power, a third lens group G3 having a positive refracting power, a fourth lens group G4 having a negative refracting power, and a fifth lens group G5 having a negative refracting power, in this order from the object side and is focused on a close subject from the infinity by moving only the fourth lens group G4 to the image surface side and satisfies conditional formulae 2.1<βrt<3.5 and 0.7<m1/√(fwxft)<1.2 whereβrt is a combined lateral magnification at the time of focusing on the infinity in the telephoto end of lens groups located nearer to the image surface side than the third lens group, m1 is an amount of movement of the first lens group during zooming from the wide angle end to the telephoto end, fw is a focal length of the zoom lens in the wide angle end, and ft is a focal length of the zoom lens in the telephoto end.</p> |
