Patent ID: 9348115
Filing Date: 2016-05-24
CPC Classification: G02B

Claim Text:
1. A photographing lens system comprising, in order from an object side to an image side: a first lens element with negative refractive power having a concave image-side surface; a second lens element having refractive power; a third lens element with positive refractive power having a convex object-side surface and a convex image-side surface; a fourth lens element with negative refractive power having a concave object-side surface, wherein the object-side surface and an image-side surface of the fourth lens element are aspheric; and a fifth lens element with positive refractive power having a convex object-side surface and a convex image-side surface, wherein the object-side surface and the image-side surface of the fifth lens element are aspheric, and at least one of the object-side surface and the image-side surface of the fifth lens element has at least one inflection point in an off-axial region thereon; wherein the photographing lens system has a total of five lens elements with refractive power, there is an air gap between any two of the first lens element, the second lens element, the third lens element, the fourth lens element and the fifth lens element that are adjacent to each other, a central thickness of the second lens element is CT2, a sum of central thicknesses of the first lens element, the second lens element, the third lens element, the fourth lens element and the fifth lens element is ΣCT, a curvature radius of the object-side surface of the fourth lens element is R7, a curvature radius of the image-side surface of the fourth lens element is R8, an axial distance between the second lens element and the third lens element is T23, and the following conditions are satisfied: