Optical image capturing system

摘要

The invention discloses a four-piece optical lens and a four-piece optical module for capturing an image. In order from an object side to an image side, the optical lens along the optical axis comprises a first lens with positive refractive power; a second lens with refractive power; a third lens with refractive power; and a fourth lens with refractive power; and at least one of the image-side surface and object-side surface of each of the four lens elements are aspheric. The optical lens can increase aperture value and improve the imaging quality for use in compact cameras.

主权项

1. An optical image capturing system, in order along an optical axis from an object side to an image side, comprising:
a first lens having positive refractive power; a second lens having negative refractive power; a third lens having refractive power; a fourth lens having refractive power; and an image plane; wherein the optical image capturing system consists of the four lenses with refractive power; at least two of the four lenses each has at least an inflection point on a surface thereof; at least one of the lenses from the second lens to the fourth lens has positive refractive power; the fourth lens has an object-side surface, which faces the object side, and an image-side surface, which faces the image side, and both the object-side surface and the image-side surface of the fourth lens are aspheric surfaces; wherein the optical image capturing system satisfies:
1.2≦f/HEP≦3.0 and 0.5≦HOS/f≦3.0; where f is a focal length of the optical image capturing system; HEP is an entrance pupil diameter of the optical image capturing system; and HOS is a distance in parallel with the optical axis from an object-side surface of the first lens to the image plane.