| 摘要 |
PROBLEM TO BE SOLVED: To achieve high imaging performance in the range from the central angle of view to a peripheral angle of view, while reducing the entire length and satisfactorily correcting various aberrations. SOLUTION: The imaging lens includes in order from the object side: a first lens L1 which has positive power and a convex face on the object side; a diaphragm St; a second lens L2 which has a meniscus shape near the optical axis; a third lens L3 which has a convex face on the image side near the optical axis and positive power near the optical axis; a fourth lens L4 both faces of which are aspherical and having the one on the image side being convex at its periphery ; and a fifth lens L5 both faces of which are aspherical and having the one on the image side being convex at its periphery. Only one of the second to fifth negative lenses L2 to L5 having the Abbe's number of 30 or below is adopted. COPYRIGHT: (C)2010,JPO&INPIT
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