Patent ID: 11231567

Abstract:
A variable magnification optical system comprises: a first lens group having a negative refractive power; at least one positive lens disposed closer to an image side than the first lens group; an aperture, the at least one positive lens being disposed between the first lens group and the aperture; an intermediate group having a plurality of lenses disposed closer to the image side than the aperture; and a vibration-reduction lens group disposed closer to the image side than the intermediate group. The plurality of lenses of the intermediate group integrally move upon varying magnification, and the system satisfies the conditional expression 1.500<f(1˜Gn)t/ft<100.000, where f(1˜Gn)t denotes a composite focal length from the first lens group to the intermediate group in a telephoto end state, and ft denotes a focal length of the entire system in the telephoto end state.