| 发明名称 | Zoom lens system, interchangeable lens apparatus and camera system | ||
| 摘要 | A zoom lens system comprising a negative first lens unit, a positive second lens unit, a negative third lens unit, and a positive fourth lens unit, wherein the second lens unit is composed of an object-side second lens unit and an image-side second lens unit, the object-side second lens unit has positive optical power, an aperture diaphragm is located between the object-side second lens unit and the image-side second lens unit, and the conditions: −0.5<f2O/f2I<1.0 and 0.12<d2O/fW<0.35 (f2O: a composite focal length of the object-side second lens unit, f2I: a composite focal length of the image-side second lens unit, d2O: an optical axial distance from a most object side lens surface of the object-side second lens unit to the aperture diaphragm, fW: a focal length of the entire system at a wide-angle limit) are satisfied. | ||
| 申请公布号 | US8780451(B2) | 申请公布日期 | 2014.07.15 |
| 申请号 | US201313754470 | 申请日期 | 2013.01.30 |
| 申请人 | Panasonic Corporation | 发明人 | Imaoka Takuya |
| 分类号 | G02B15/14;G02B9/00;G02B13/04 | 主分类号 | G02B15/14 |
| 代理机构 | McDermott Will & Emery LLP | 代理人 | McDermott Will & Emery LLP |
| 主权项 | 1. A zoom lens system, in order from an object side to an image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power, a third lens unit having negative optical power, and a fourth lens unit having positive optical power, wherein the second lens unit is, in order from the object side to the image side, composed of an object-side second lens unit and an image-side second lens unit, the object-side second lens unit has positive optical power, an aperture diaphragm is located between the object-side second lens unit and the image-side second lens unit, and the following conditions (1) and (2) are satisfied: −0.5<f2O/f2I<1.0 (1)0.12<d2O/fW<0.35 (2) where f2O is a composite focal length of the object-side second lens unit, f2I is a composite focal length of the image-side second lens unit, d2O is an optical axial distance from a most object side lens surface of the object-side second lens unit to the aperture diaphragm, and fW is a focal length of the entire system at a wide-angle limit. | ||
| 地址 | Osaka JP | ||