LED LIGHT SOURCE

PROBLEM TO BE SOLVED: To provide a fixed focus lens including a first lens group and a second lens group, which have positive refractive powers. SOLUTION: The first lens group mainly has first, second, third, fourth and fifth lenses arranged in order from an object side to an image side. The refractive powers of the first to the fifth lenses are negative, negative, negative, positive, and positive respectively. The first lens is an aspherical lens. The second lens group is arranged between the first lens group and image side, and mainly has sixth, seventh, eighth, ninth, tenth lenses in order from the object side to the image side. The sixth and seventh lenses construct a first cemented lens, and the ninth and tenth lenses construct a second cemented lens. COPYRIGHT: (C)2008,JPO&INPIT