| 摘要 |
A wide-angle lens system having a long back focal length, disposed in front of a 1/3'' CCD camera and the focal length (f) for all lens groups is 3.0 mm, the F-number is 3.0 and the half-field angle is 46°. The following conditions are met by the first lens group: 1<=D/D3<1.2; R3/R2=0.99; and d2/f=0.03. Here, (d) indicates the thickness of the second lens along the normal line at a given distance from the optical axis within the maximum effective diameter of the object side convex surface of the lens. d3 is the thickness of the second lens along the optical axis.
|
