Lens barrel having an image blur prevention system with improved

Abstract

A lens barrel having an image blur prevention system incorporated into the lens barrel. The image blur prevention system includes an image blur prevention optical system which is arranged to eliminate the problem of harmful light entering the lens barrel. The lens barrel includes an aperture unit having an aperture stop which is positioned in the path of a main optical system, and a filter optical system which is secured to a filter retainer frame and positioned so that a specified interval is maintained between the filter retainer frame and the aperture stop. The image blur prevention optical system, which is moved in a plane perpendicular to the optical axis of the main optical system to prevent image blur, is located between the aperture stop and the filter optical system. When the image blur prevention optical system is moved to prevent image blur, the aperture stop and the retainer frame block harmful light. Further, an image blur prevention drive mechanism of the image blur prevention optical system is incorporated into a space between a retainer member of the aperture unit and a retainer member which holds the filter retainer frame to prevent dirt or dust from entering the drive mechanism.