Patent ID: 7389040

Claim:
A lens barrel comprising: a radially-retractable optical element constituting a part of photographing optical system, said radially-retractable optical element being movable between a photographing position located on an optical axis of said photographing optical system, and a radially-retracted position located on an off-optical-axis position; a biasing device for biasing said radially-retractable optical element toward said photographing position; and a swing member which is rotatable about a rotation axis extending parallel to said optical axis, said swing member being rotated so as to push said radially-retractable optical element against a biasing force of said biasing device to move said radially-retractable optical element to said radially-retracted position; wherein said radially-retractable optical element and said swing member are mutually positioned so that a moving amount of said radially-retractable optical element per unit of rotation angle of said swing member gradually decreases as said radially-retractable optical element moves from said photographing position to said radially-retracted position.