Patent ID: 6115190
Filing Date: 2000-09-05
Classification: G02B

Abstract:
A zoom lens barrel comprising:a fixed tube provided at a camera body;a first rotary tube arranged to move in an optical axis direction relative to said fixed tube and rotate around the optical axis during zooming, said first rotary tube having a helical groove formed on an inner surface thereof,a first rectilinear member disposed inside said first rotary tube and arranged to rectilinearly move in the optical axis direction integrally with said first rotary tube;a second rotary tube disposed inside said first rotary tube and arranged to rotate in the same rotating direction as that of said first rotary tube in association with rotation of said first rotary tube; anda second rectilinear member disposed inside said second rotary tube, having a projecting part engaging said helical groove and prevented by said first rectilinear member from rotating around the optical axis,wherein the rotation of said first rotary tube causes said second rectilinear member to move in the optical axis direction according to a locus of said helical groove, thereby causing said second rotary tube to move in the optical axis direction.