| 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 f 1 , 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 √d 2 , the following conditional expressions are satisfied. 0.50<f 1 /f<1.5 (1) 0.50<Sigmad/f<1.5 (2) 50>√d 2 (3). Accordingly, a small, low-cost imaging lens capable of high-quality imaging can be realized.
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