Patent ID: 6522478
Filing Date: 2003-02-18
Classification: G02B

Abstract:
A multi-stage-extension zoom lens barrel assembly having a helicoid structure for allowing movement of a lens barrel in an optical axis direction, the helicoid structure including a first inner peripheral helicoid ring having a first helicoid formed on the outer periphery thereof and an outer peripheral helicoid ring having a second helicoid formed on an inner periphery thereof for engaging with said first helicoid, said multi-stage-extension zoom lens barrel assembly comprising:a first linear guide ring provided in said first inner peripheral helicoid ring so that said first linear guide ring is relatively rotatable and integrally movable in the optical axis direction together with said first inner peripheral helicoid ring; and a first outer barrel for externally covering said first linear guide ring, said first outer barrel and said first inner peripheral helicoid ring being formed separately from each other, said first outer barrel being supported on said first linear guide ring so as to relatively rotate and move in the optical axis direction together with the first linear guide ring, wherein said first outer barrel is detachably attached to said first inner peripheral helicoid ring, said first outer barrel being integrally rotatable about the optical axis and integrally movable along the optical axis with said first inner peripheral helicoid ring.