| 摘要 |
The imaging lens includes, in order from the object side, a first lens having positive refractive power, a second lens having positive refractive power, and a third lens having negative refractive power. The first lens is provided with a substrate portion which is a parallel plate, and a lens portion formed of a material having a refractive index different from that of the substrate portion on at least one of the object-side surface or the image-side surface of the substrate portion, and the second lens is a single lens and satisfies the following conditional expression: 1<f2/f<20, wherein f2 represents the focal length of the second lens and f represents the focal length of the entire imaging lens system.
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