Lens device

A lens device comprising:

• a zoom lens;
• and
• a controller,
• wherein the zoom lens consists of a first lens group in which all lens distances do not change during zooming and an image-side lens group of which a distance from the first lens group in an optical axis direction changes during zooming in order from an object side to an image side,
• a stop, at least one focusing lens group positioned within the image-side lens group, and an aberration correction lens group, which does not include a lens closest to the object side, performs aberration correction by moving along an optical axis, and has a refractive power lower than a refractive power of the focusing lens group having the lowest refractive power, are disposed within the zoom lens,
• only the at least one focusing lens group moves or only the at least one focusing lens group and the aberration correction lens group move during focusing from an object at infinity to an object within a short range,
• assuming that a transverse magnification of each focusing lens group in a state in which the zoom lens focuses on the object at infinity at a wide-angle end is βfw, a combined transverse magnification of all the lenses closer to the image side than the focusing lens group is βrw, the βrw is 1 in a case where there is no lens disposed so as to be closer to the image side than each focusing lens group, and Fs is defined as Fs=|(1−βfw2)×βrw2|, the focusing lens group of which the Fs is maximized is determined as a maximum focusing lens group, and
• in a case where a condition is changed to a second condition different from a first condition with a predetermined position of the aberration correction lens group relative to the maximum focusing lens group as a reference for the first condition, the controller adjusts the position of the aberration correction lens group relative to the maximum focusing lens group for each zoom position according to the changed condition.