Patent attributes
A tilt lens system includes a focus lens unit movable during focusing; a diaphragm sharing a primary optical axis with the focus lens unit; and a tilt lens unit, arranged on an image side of the focus lens unit and the diaphragm, having a negative refractive power and an optical axis tiltable with respect to the primary optical axis. Conditional Expressions (1) and (2) are satisfied as follows,1.3<βt<1.7 (1)0<P<H1 (2)where βt is a lateral magnification of the tilt lens unit in a not tilted state, P is a distance from a most object side surface of the tilt lens unit to a rotating center of the tilt lens unit in a tilted state, and H1 is a distance from the most object side surface of the tilt lens unit to a first principal point of the tilt lens unit.