An optical system is provided. In order from an object side to an image side, the optical system includes a first lens element having a positive power, a meniscus shape, and an object side surface. The object side surface of the first lens element is convex toward the object side. A second lens element has a negative power, a meniscus shape, and an object side surface. The object side surface of the second lens element is concave toward the object side. A third lens element has a positive power. An aperture stop is positioned on or in front of an object side of the first lens element.