Image capturing optical system
AssigneeLargan Precision Co., Ltd.
InventorsDung-Yi Hsieh, Ming-Ta Chou
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Abstract
An image capturing optical system includes, in order from an object side to an image side: the first lens element with positive refractive power having a convex object-side surface, the second lens element with positive refractive power having a concave object-side surface and a convex image-side surface, the third lens element with positive refractive power having a concave object-side surface and a convex image-side surface, wherein the object-side surface and the image-side surface of the third lens element are aspheric. By such arrangement, the total track length and the photosensitivity of the image capturing optical system can be effectively reduced while retaining high image quality. The image capturing optical system can also be applied to an infrared optical system.
Claims19
An image capturing optical 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 positive refractive power having a concave object-side surface and a convex image-side surface;
- and
- a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface, wherein the object-side surface and the image-side surface of the third lens element are aspheric, and the third lens element is made of plastic material;
- wherein the image capturing optical system has a total of three lens elements with refractive power, a focal length of the image capturing optical system is f, a focal length of the second lens element is f2, and they satisfy the following relationship:
- 1.2<f/f2<2.4.
An image capturing optical 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 positive refractive power having a concave object-side surface and a convex image-side surface;
- and
- a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface, wherein the object-side surface and the image-side surface of the third lens element are aspheric, and the third lens element is made of plastic material;
- wherein the image capturing optical system has a total of three lens elements with refractive power, a focal length of the image capturing optical system is f, a focal length of the third lens element is f3, and they satisfy the following relationship:
- 0.0<f/f3<0.3.
Dependencies are inferred from the claim text.