Abstract: A lens centering apparatus of a lens barrel having therein a lens supporting frame includes male threads provided on an outer periphery of the lens supporting frame, and female thread sets provided on the lens barrel and having different centers. The female thread sets can be selectively engaged by the male threads of the lens supporting frame.

Abstract: An adjusting mechanism of a lens barrel of a camera, including a lens supporting member which supports a photographing optical system, a camera body which supports the lens supporting member in a movable fashion in an optical axis direction of the photographing optical system, and a spring member for biasing the lens supporting member forwardly in the optical axis direction. The mechanism further includes a connecting member which restricts a movement of the lens supporting member to a maximum projecting position against a restoring force of the spring member in the optical axis direction with respect to the camera body while permitting the lens supporting member to move rearwardly against the restoring force of the spring member in the optical axis direction.

Abstract: A linear guiding mechanism of a zoom lens barrel including a stationary barrel which is fixed to a camera body, a cam ring which is threadedly engaged with the stationary barrel on an inside of the stationary barrel, and a linear guiding plate for linearly guiding a photographing optical system in an optical axis direction. The linear guiding plate is movable together with the cam ring in the optical axis direction, and the linear guiding plate is rotatable with respect to the cam ring. A linear guiding portion is provided on the stationary barrel for guiding the linear guiding plate in the optical axis direction. A section of the linear guiding potion is formed as an elongated hole. The remaining section of the linear guiding portion is formed as a blind-end groove on an inner peripheral surface of the stationary barrel.