Abstract: A zoom lens for a video camera includes a focusing mechanism which is designed to prevent a picked-up image from shaking when the focusing mechanism is operated manually or electrically. In the focusing mechanism, a female helicoid is threadedly fitted on a male helicoid, and a female helicoid holder supports the female helicoid from a lower side of the female helicoid to maintain a proper threaded engagement between the female helicoid and the male helicoid. The female helicoid holder is provided at a lower side of the male helicoid.

Abstract: Optical apparatus comprises an optical element and a moving mechanism having two members arranged to move the optical element in the direction of an optical axis thereof by moving one of the two members in the direction of the optical axis relative to the other while rotating said two members relative to each other. The two members include a male helicoid member having a male helicoid screw and a female helicoid member having a female helicoid screw arrangement in screw engagement with the male helicoid screw, the female helicoid screw arrangement providing only a single screw thread peripherally interiorly of the female helicoid member along an axis parallel to the optical axis.

Abstract: A rolling ball element mount and barrel interface comprises a barrel and an element mount sharing a common lateral (X, Y, Z) and angular (.THETA..sub.X, .THETA..sub.Y, .THETA..sub.Z) frame of reference located at a center of said barrel, the element mount adapted to fit inside the barrel axially along Z. A first component, including at least two rolling balls, is disposed between and adapted for contact with the element mount and the barrel for (i) constraining the element mount in lateral positions X and Y and angular positions .THETA..sub.X and .THETA..sub.Y and (ii) moveably coupling the element mount and the barrel in the axial direction. A second component, including at least one rolling ball, is disposed between and adapted for contact with the element mount and the barrel for (iii) constraining the element mount in angular position .THETA..sub.Z in cooperation with the first component and (iv) moveably coupling the element mount and the barrel in the axial direction.

Abstract: A lens barrel is provided having a screw mount. The lens barrel includes a mount ring having a threaded portion, which can be engaged by a corresponding screw mount of the camera body to which the lens barrel is to be attached, a focus adjusting ring which is rotatably supported by the mount ring, a barrel body which is screw-engaged by the focus adjusting ring to support a focus adjusting lens, a linear movement guide member which is rotatably supported by the mount ring to restrict the movement of the barrel body so as to move only in the optical axis direction of the focus adjusting lens, and a frictional resisting member which resists the rotational movement of the linear movement guide member relative to the mount ring.

Abstract: A zoom lens barrel is disclosed with includes a stationary barrel. A rotatable cam ring is supported by the stationary barrel and is adapted to move along an optical axis direction in association with rotation of the rotatable cam ring. A lens guide ring is adapted to move together with the cam ring along the optical axis direction, and the cam ring is adapted to rotate relative to the lens guide ring, in association with axial movement of the cam ring. Cam grooves are provided for guiding the movement of at least two movable front and rear lens groups, with at least one groove being formed on the cam ring. Lens guide grooves are formed on the lens guide ring and are adapted to correspond to the cam grooves of the cam ring. At least one guide pin is provided which is adapted to extend through an associated cam groove and an associated lens guide groove.

Abstract: A lens barrel for a waterproof or dustproof camera which can assure maintenance of a reliable liquid-tight or airtight condition between a movable lens barrel member and a fixed lens barrel member with a structure of a comparatively small size. The lens barrel comprises a fixed lens barrel member provided on a camera body, a movable lens barrel member mounted for movement on the fixed member between a position advanced outwardly from the camera body and another position retracted in the camera body, and a bellows member secured at an end thereof to an inner periphery of a rear portion of the movable member and at the other thereof to an inner periphery of a rear portion of the fixed member. The bellows member is folded back at an intermediate portion thereof between the movable member and the fixed member in such a manner as to surround a rear end of the movable member, and the folded back portion moves as the movable member is moved between the retracted position and the advanced position.