| 摘要 |
PROBLEM TO BE SOLVED: To obtain an image pickup lens which is suitable for image capture of a mobile terminal, etc., and whose overall length is short by arraying two positive lenses, and a negative lens both surfaces of which are aspherical and which gradually decreases in negative power as going from the lens center to the circumference to have positive power at the circumferential part and is concave the image side in order from the object side. SOLUTION: Arranged from the object side are a 1st lens L1 composed of a positive meniscus lens which is convex to the object side, a stop 2, a 2nd lens L2 composed of a positive meniscus lens which is convex to the image side, a 3rd lens L3 which is composed of a negative lens concave to the image side and both surfaces of which are aspherical and which gradually decreases in negative power as going from the lens center to the circumference to have the positive power at the circumferential part, a cover glass 1, and an imaging element 3. The image-side aspherical surface of the 3rd lens L3 satisfies a conditional equation (1) 0.7H<DZ|<SB>0</SB><1.0H (H: the effective diameter of the 3rd lens, DZ|<SB>0</SB>: the height of a point on the aspherical surface where the tilt (DZ) of the tangent plane to the tangent plane at the aspherical surface peak is 0 from the optical axis). COPYRIGHT: (C)2004,JPO
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