| 摘要 |
An optical system is disclosed. The optical system includes a first lens, a second lens, and a third lens which are consecutively arranged from an object side to an image side and satisfy the following formula 1 and formula 2: [Formula 1] -2<R7/F<10.25<¦(Sag S5/SD S5)¦<0.5 Here, R7 is the radius of curvature of the third lens image side surface, F is the overall effective focal length, Sag S5 is a Sag value within the radius of investigation of the second lens image side surface, and SD S5 is the radius of investigation of the second lens image side surface. [Formula 2] 25<Φ(refractive)/Φ(diffractive)<50 Here, Φ(refractive) is a power due to refraction of the first lens and Φ(diffractive) is a power due to diffraction of the first lens. |
