Optical image capturing lens system

摘要

An optical image capturing 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 with positive refractive power has a convex object-side surface. The second lens element has negative refractive power. The third lens element has positive refractive power, wherein an object-side surface and an image-side surface of the third lens element are aspheric. The fourth lens element with refractive power is made of plastic material and has a concave image-side surface, wherein an object-side surface and the image-side surface of the fourth lens element are aspheric, and the fourth lens element has at least one inflection point formed on at least one of the object-side surface and the image-side surface thereof.

主权项

1. An optical image capturing lens system comprising, in order from an object side to an image side:
a first lens element with positive refractive power having a convex object-side surface; a second lens element with negative refractive power made of plastic material, wherein both of an object-side surface and an image-side surface of the second lens element are aspheric; a third lens element with positive refractive power, wherein an object-side surface and an image-side surface of the third lens element are aspheric; and a fourth lens element with refractive power made of plastic material and having a concave image-side surface, wherein an object-side surface and the image-side surface of the fourth lens element are aspheric, and the fourth lens element has at least one inflection point formed on the image-side surface thereof; wherein the optical image capturing lens system has a total of four lens elements with refractive power, a distance perpendicular to an optical axis between the inflection point on the image-side surface of the fourth lens element and the optical axis is Yc42, an effective radius of the image-side surface of the fourth lens element is SD42, a maximum effective radius of the surfaces of the first through fourth- lens elements is SDmax, and a minimum effective radius of the surfaces of the first through fourth lens elements is SDmin, a focal length of the optical image capturing lens system is f, and an entrance pupil diameter of the optical image capturing lens system is EPD, the following relationships are satisfied:
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