Patent attributes
A zoom lens includes a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, a fourth lens group which has negative refractive power and is configured with only a single lens, and a fifth lens group having positive refractive power, which are arranged in order from an object side to an image side. During zooming, at least the first lens group, the second lens group, the third lens group, and the fourth lens group are movable in an optical axis direction. Focusing from infinity to a close range is performed by the fourth lens group being moved in the optical axis direction. At least one of following conditional expressions (1) and (2) is satisfied.−11.0<Fno—w×Y/{(1−β4—w2)×β5—w2}<−7.0 and (1)−11.0<Fno—t×Y/{(1−β4—t2)×β5—t2}<−7.0 (2)
