| 摘要 |
PURPOSE:To realize a zoom lens of a small size which has a high magnification containing a wide view angle by constituting so that the whole lens system of four lens groups can move, and also a specific condition is satisfied with regard to a focal distance of the first lens group and a focal distance of the second lens group. CONSTITUTION:When executing a zooming to a telephoto end (fT) from a wide angle end (fW), this zoom lens is constituted so that the first lens group G1 and the fourth lens group G4 move monotonously by the alsmot same quantity toward an object side, also the third lens group G3 moves monotonously toward the object side in a ratio of about 0.4-0.5 times of a movement of the first lens group G1, and simultaneously, the second lens group G2 moves toward the object side at least in the vicinity of the wide angle end. Also, the titled zoom lens which is small-sized and scarcely causes an aberration variation is obtained by constituting it so that a conditional expression I is satisfied between a focal distance f1 and a focal distance f2 of the first lens group, and making it correspond to a high variable power zoom of about 5.7 times. |
