| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensive photographic lens whose aberration is corrected so as to obtain a faithful image and where an optical system is constituted to be short and small to be compact. SOLUTION: The photographic lens 10 has a 1st lens 1 and a 2nd lens 2 which are meniscus lenses made of the same material arrayed in order from an object side, and the 1st lens 1 turns its convex surface to the object side and has positive refractive power and the 2nd lens 2 turns its convex surface to an image surface side and has positive refractive power, and aspherical correction is performed to lens surfaces 1a, 1b and 2b so that following conditional expressions (1) to (3) may be satisfied. (1) 1.5<f1/f<2.5, (2) 1.2<f1/f2<1.8 and (3) 0.48≤R1/f≤1.0 where, (f) means the focal distance of the entire optical system, f1 means the focal distance of the 1st lens, f2 means the focal distance of the 2nd lens and R1 means the radius of curvature of the object side lens surface of the 1st lens. COPYRIGHT: (C)2003,JPO
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