| 摘要 |
PROBLEM TO BE SOLVED: To provide a fixed-focus lens which is disposed between a primary image side and a secondary image side. SOLUTION: The fixed-focus lens 100 includes a second lens group 110, a first lens group 130 and a curved reflecting mirror which are arranged in the order starting from a primary-image side to a secondary-image side. The second lens group includes a first lens 112, a second lens 114 and a third lens 116, arranged in the order starting from the primary-image side to the secondary-image side. The refractive power of the first lens and the third lens are both positive, and all the first, second and third lenses are spherical lenses. COPYRIGHT: (C)2010,JPO&INPIT |
