| 摘要 |
PURPOSE: An objective lens system for thermal image device is provided to increase an image angle and brightness and to improve resolution performance up to an edge area by placing an opening diaphragm between a first lens and a second lens. CONSTITUTION: A first lens(10) is composed of the non-spherical lens swollen toward an object side of the meniscus form. On the whole, the refractive power of the plus is taken. A second lens(20) is composed of a non-spherical lens of the meniscus form swollen toward the viewing side. The refractive index of amount is taken. An iris diaphragm(30) is arranged between the first lens and the second lens. |
