OPTICAL SYSTEM

Abstract

An optical system includes a first lens having negative refractive power and having two concave surfaces, a second lens having positive refractive power, a third lens having refractive power, a fourth lens having refractive power, a fifth lens having refractive power, a sixth lens having refractive power, and a seventh lens having refractive power. The first to seventh lenses are sequentially disposed from an object side.

Description

Claims

1. An optical system comprising: a first lens having negative refractive power, a concave object-side surface and a concave image-side surface;a second lens having positive refractive power and a convex object-side surface;a third lens having positive refractive power and a convex object-side surface;a fourth lens having positive refractive power;a fifth lens having negative refractive power;a sixth lens having positive refractive power; anda seventh lens having negative refractive power,wherein the first to seventh lenses are sequentially disposed from an object side, andwherein the optical system has a total of seven lenses.

2. The optical system of claim 1, wherein 53° < ANG/Fno < 61° is satisfied, ANG being a field of view of the optical system and Fno being a constant indicating brightness of the optical system.

3. The optical system of claim 1, wherein ANG ≥ 90° is satisfied, ANG being a field of view of the optical system.

4. The optical system of claim 1, wherein the fourth lens has a convex object-side surface.

5. The optical system of claim 4, wherein the fourth lens has a convex image-side surface.

6. The optical system of claim 1, wherein the fifth lens has a concave object-side surface.

7. The optical system of claim 6, wherein the fifth lens has a convex image-side surface.

8. The optical system of claim 1, wherein the sixth lens has a convex object-side surface.

9. The optical system of claim 8, wherein the sixth lens has a convex image-side surface.

10. The optical system of claim 9, wherein the seventh lens has a convex object-side surface.

11. The optical system of claim 10, wherein the seventh lens has a concave image-side surface.

12. The optical system of claim 1, wherein the seventh lens has an inflection point formed on either one or both of an object-side surface of the seventh lens and an image-side surface of the seventh lens.