Abstract: A lens assembly including an adjusting mechanism arranged to render a part or parts of or all of the optical elements, constituting an optical system, movable by an electric motor drive arrangement, the lens barrel is composed of a stator or stators of one or a plurality of linear motors for driving the adjusting mechanism. The movable element of the linear motor corresponding with the stator is formed into a hollow space, in which each of the movable optical elements can be accommodated.

Abstract: A lens assembly including an adjusting mechanism arranged to render a part or parts of or all of the optical elements, constituting an optical system, movable by an electric motor drive arrangement, the lens barrel is composed of a stator or stators of one or a plurality of linear motors for driving the adjusting mechanism. The movable element of the linear motor corresponding with the stator is formed into a hollow space, in which each of the movable optical elements can be accommodated.

Abstract: The present invention relates to a device to adjust the position of optics lens systems which are movable relative to each other, and is characterized in that the device is equipped with a plural number of cam grooves variable relative to each other to adjust the position, frames to support the optical elements composing said optic lens system and springs forcing said frames to always be engaged in said adjusting cam grooves, whereby the forcing springs present forcing forces to compensate the components along the directions to move said adjusting cam grooves of the forces given to said plural number of said adjusting cam grooves.

Abstract: A lubrication unit is provided for lubricating drive and driven members used in a film apparatus which continuously feeds a film in a small size motion picture camera, a motion picture projector, a still camera incorporating a motor drive or the like. The unit includes lubrication means for lubricating engaging parts of a drive member that is rotatively driven and a driven member which is held in engagement with the drive member when the drive member is driven at a high speed. The lubrication means includes a lubricant storage in either a drive member or driven member, the lubricant storage communicating with the engaging surfaces of the drive and driven members to supply a controlled amount of lubricant thereto under the influence of the centrifugal force that is developed upon rotation of either drive or driven member.