| 摘要 |
PROBLEM TO BE SOLVED: To obtain an imaging lens miniaturized as an entire lens system, having excellent optical performance and easily manufactured while securing complete telecentric characteristics, and an imaging apparatus having the same. SOLUTION: The photographic lens has, in order from an object side to an image side, an aperture stop, a first lens having positive refractive power, whose surfaces on the object side and the image side are convex, a second lens having negative refractive power, whose surfaces on the object side and the image side are concave, a third lens having positive refractive power, whose surface on the image side is convex, and a fourth lens having negative refractive power. The first, the third and the fourth lenses have at least one aspherical surface respectively, and the material of the respective lenses is resin. When the refractive index and the Abbe number of the material of the first lens are defined as N1 andν1 respectively, and the Abbe number of the material of the second lens is defined asν2, they satisfy conditions; N1<1.540 andν1>ν2. COPYRIGHT: (C)2008,JPO&INPIT
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