| 摘要 |
An imaging lens ( 100 ) comprising, arranged sequentially from the object side, a positive-meniscus first lens ( 1 ) with its convex plane facing the object side, a negative-power-meniscus second lens ( 2 ), and a positive-power third lens ( 3 ), the second and third lenses ( 2, 3 ) functioning as correction lenses. The first lens ( 1 ) has a strong power, and both the second and third lenses ( 2, 3 ) are aspherical on opposite planes. When the synthetic focal distance of the imaging lens is f, the focal distance of the first lens f1, the distance from the incident surface on the object side to the imaging surface of the first lens ( 1 ) Sigmad, and the Abbe number of the second lens {square root}d2, the following conditional expressions are satisfied. 0.50<f1/f<1.5 (1) 0.50<Sigmad/f<1.5 (2) 50>{square root}d2 (3). Accordingly, a small, low-cost imaging lens capable of high-quality imaging can be realized.
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