| 摘要 |
Providing an optical system having excellent optical performance over entire focusing range from infinity to a close distance, a method for focusing the optical system, and an imaging apparatus equipped therewith. The optical system includes, in order from an object, a first lens group (G1) having positive refractive power, and a second lens group (G2) having positive refractive power. The second lens group (G2) is movable along an optical axis for varying focusing. The first lens group (G1) satisfies a given conditional expression.
In a further aspect, two negative lenses in the second lens group (G2) satisfy conditional expresions concerning an Abbe number and refractive index. |
