Patent ID: 10816782

Abstract:
A variable magnification optical system comprising a positive first lens group G1 disposed at a most object side, a negative second lens group G2 disposed at an image side of the first lens group G1 and a positive rear group GR disposed at an image side of the second lens group G2, upon varying magnification from an wide angle end state to a telephoto end state, the first lens group G1 being moved toward the object side, a distance between the first lens group G1 and the second lens group G2 and a distance between the second lens group G2 and the rear group GR being varied, and the rear group GR comprising a focusing group that is moved upon focusing, an A group having positive refractive power and a B group satisfying a given conditional expression with respect to the A group and having negative refractive power. Thus, the variable magnification optical system has excellent optical performance and the focusing group reduced in weight in order to attain high speed focusing operation.