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) .SIGMA.d, and the Abbe number of the second lens d2, the following conditional expressions are satisfied. 0.50<f1/f<1.5 (1) 0.50<.SIGMA.d/f<1.5 (2) 50> d2 (3). Accordingly, a small, low-cost imaging lens capable of high-quality imaging can be realized.
An object is to provide an imaging lens system which can achieve reduction of the size and weight while maintaining the high optical performance. The imaging lens system of the present invention comprises, in order form an object side to an imaging surface side: a first lens having a positive power with its convex surface facing the object side; a second lens in a meniscus shape having a positive power with its concave surface facing the object side; and a third lens functioning as a correction lens, wherein the imaging lens system satisfies following expressions: 0.25<r.sub.1/f<0.50, and -0.27<r.sub.3/f<-0.19 (where, r.sub.1: a radius of center curvature of the surface (first face) of the first lens on the object side, r.sub.3: a radius of center curvature of the surface (first face) of the second lens on the object side, f: a focal distance of an entire lens system).
