| 摘要 |
A lens system includes a main lens and a transfer lens aligned with the main lens. The optical axis of the main lens is superposed on that of the transfer lens. The transfer lens includes, in order from the object side to the image side thereof, a first lens having negative refraction power, and a second lens having positive refraction power. The lens system satisfies the following conditions: 0.4<|f1/f2|<0.8; 2<v1/v2<3.8; 0.86<N1/N2<1.12; wherein, f1 is a focal length of the first lens, f2 is a focal length of the second lens, v1 is an Abbe constant of the first lens, v2 is an Abbe constant of the second lens, N1 is a refractive index of the first lens, N2 is a refractive index of the second lens. |
