| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact zoom lens system which is used for a video camera and a digital still camera, and has a high image-forming performance over the whole zooming range irrespective of distance to an object while covering a wide-photographic side up to a telephotographic side, and to provide an image pickup unit using the zoom lens system. SOLUTION: The zoom lens system comprises: sequentially from an object side, a 1st lens group GR1 including positive, negative, positive, positive, weak refracting power (including refracting power = 0), and negative refracting power, respectively; a 2nd lens group GR2; a 3rd lens group GR3; a 4th lens group GR4; a 5th lens group GR5; and a 6th lens group GR6, and when group spacing between an i-th lens group and a j-th lens group at a wide-photographic end is expressed by DW(i-j), and group spacing between an i-th lens group and a j-th lens group at a telephotographic end is expressed by DT(i-j), the zoom lens system satisfies the following formulae (1) to (3), and performs focusing by the above 4th lens group. (1) is DW(1-2)<DT(1-2), (2) is DW(2-3)>DT(2-3), and (3) is DW(5-6)>DT(5-6). COPYRIGHT: (C)2006,JPO&NCIPI |
