Patent ID: 7623151
Filing Date: 2009-11-24
Classification: G02B,G03B,H04N

Abstract:
1. A lens device comprising: a vibration correcting lens; a shift frame which holds the vibration correcting lens and is movable in a direction orthogonal to an optical axis of the lens device; a shift base which is adapted to prevent the shift frame from moving in the optical axis direction; a ball which is disposed and supported between the shift frame and the shift base and is relatively movable with respect to each of the shift frame and the shift base; a limiting portion which is provided so as to limit a movable range of a relative movement of the ball; and a drive unit which (a) has a magnet, a yoke, and a coil and (b) drives the shift frame in a direction orthogonal to the optical axis by applying electrical current to the coil, the magnet being held by one of the shift frame and the shift base, and the yoke and the coil being held by another of the shift frame and the shift base, wherein the size of the movable range of the limiting portion in a driving direction of the shift frame is set so that the ball does not contact the limiting portion even when the ball rolls from a center of the movable range by half of a maximum movement amount of the shift frame, and the maximum movement amount is (a) a maximum movement amount when the shift frame is mechanically moved or (b) a maximum movement amount when the shift frame is moved to correct an image vibration, and wherein the shift frame is biased toward the shift base using a magnetic attractive force in the optical axis direction occurring between the magnet and the yoke.