Lens assembly

A lens assembly includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens. The first lens is with negative refractive power and includes a concave surface facing an image side. The second lens is with positive refractive power and includes a convex surface facing an object side. The third lens is with positive refractive power. The fourth lens is with negative refractive power. The fifth lens is a meniscus lens with positive refractive power. The sixth lens is with positive refractive power and includes a concave surface facing the imaget side. The first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are arranged in order from the object side to the image side along an optical axis. An air gap is between the third lens and the fourth lens.