Subminiature optical system and portable device including the same
AssigneeSamsung Electro-Mechanics Co., Ltd.
InventorsYong Joo Jo, Young Suk Kang
Life of this patent
Estimating the term…
Abstract
There are provided a subminiature optical system having a miniature size and capable of obtaining a narrow view angle using only five sheets of lenses, and a portable device having the same. The subminiature optical system includes a first lens convex toward the object side and having positive refractive power, a second lens concave toward an image side and having negative refractive power, a third lens convex toward the object side and having positive refractive power, a fourth lens concave toward the image plane and having negative refractive power, and a fifth lens convex toward the image plane and having negative or positive refractive power, sequentially from an object side.
Claims15
An optical system, comprising:
- a first lens having positive refractive power;
- a second lens;
- a third lens;
- a fourth lens having a concave object-side surface and a concave image-side surface;
- and
- a fifth lens having positive refractive power, a concave object-side surface in a paraxial region and a convex image-side surface in the paraxial region,
- wherein the first lens to fifth lens are sequentially disposed from an object side,
- wherein the optical system has a total of five lenses, and
- wherein TTL is a distance on an optical axis between an object-side surface of the first lens and an image plane of an image sensor, F is a focal length of the optical system, and 0.7<TTL/F<1.0.
An optical system, comprising:
- a first optical system;
- and
- a second optical system having a view angle narrower than that of the first optical system,
- the second optical system comprising:
- a first lens having positive refractive power;
- a second lens;
- a third lens;
- a fourth lens having a concave object-side surface and a concave image-side surface;
- and
- a fifth lens having positive refractive power, a concave object-side surface in a paraxial region and a convex image-side surface in the paraxial region,
- wherein the first lens to fifth lens are sequentially disposed from an object side,
- wherein the second optical system has a total of five lenses, and
- wherein a view angle difference between the view angle of the first optical system and the view angle of the second optical system is greater than 25 degrees and less than 80 degrees, and
- wherein the second optical system satisfies the following conditional expression:
- 0.7<TTL/F<1.0
- where TTL is a distance on an optical axis between an object-side surface of the first lens and an image plane of an image sensor, and F is a focal length of the second optical system.
Dependencies are inferred from the claim text.