US Patent 10139594 Optical imaging lens system, image capturing unit and electronic device

An optical imaging 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 and a fourth lens element. The first lens element has positive refractive power. The second lens element has negative refractive power. The fourth lens element has an object-side surface being concave in a paraxial region thereof, wherein at least one of the object-side surface and an image-side surface of the fourth lens element has at least one inflection point. The optical imaging lens system has a total of four lens elements.