Patent attributes
A monofocal optical lens system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has negative refractive power. The third lens element has refractive power, wherein at least one of the surfaces thereof is aspheric. The fourth lens element with negative refractive power is made of plastic material, and has a concave object-side surface and a convex image-side surface. The fifth lens element with refractive power is made of plastic material, and has a concave object-side surface, wherein the image-side surface thereof is convex or planar at the paraxial region and is convex at the peripheral region, and the surfaces of the fourth through fifth lens elements are aspheric.