US Patent 11402652 Optical unit with shake correction function

A retainer of a rotation support structure may include an outer protrusion on the outer circumference side of a spherical-object holding hole and an inner protrusion on the inner circumference side thereof. The outer protrusion may be in contact with a plate-holder circular arc wall of a plate-holder annular portion, and the inner protrusion may be in contact with a plate-roll annular wall of a plate-roll annular portion. When the plate-roll annular portion and the plate-holder annular portion shift with respect to the identical axis, the relative movement between the plate-roll annular portion and the plate-holder annular portion in the radial direction may be transmitted to a spherical object via the outer protrusion. Also, the relative movement may be transmitted to the spherical object via the inner protrusion, which makes the spherical object active.