Abstract: A filter mounting mechanism capable of attachment to and detachment from an optical assembly such as the interchangeable lens assembly of a single lens reflex camera is provided with a holding member arranged to rotatably carry a filter in such a manner that the filter may be rotated from externally of the optical assembly in order to enable adjustment of the filter. The mechanism includes a device for preventing the filter from becoming loosened while in use and the arrangement further operates to facilitate use of a thin film filter such as a gelatin filter in cases where such a filter is to be used by preparation and cutting thereof into a desired size and shape.

Abstract: Formed in a movable sleeve of a lens mounting are axial guide portions and cutout portions imparting to the guide portions an elastic deformation when the guide portions are brought into fitting engagement with respective guide grooves of a fixed sleeve.

Abstract: In a vibration motor, electrostrictive elements arranged or polarized phase-differentially are bonded to a plurality of concentric ring-shaped vibration members arranged on at least one of a stator and a rotor, voltages are applied to the electrostrictive elements to generate travelling vibration waves in the vibration members and the rotor contacting to the vibration members is friction-driven by the travelling vibration wave.

Abstract: A focus presetting mechanism for a camera lens assembly including an annular member fitted on the outer diameter of the lens assembly and rotatable relative thereto about the optical axis thereof which may be clamped at a fixed angular position in order to establish a predetermined focusing point at which the focusing ring of the lens assembly may be stopped. Stop members operatively interposed between the annular member and the focusing ring enable the focusing ring to be repeatedly returned to a predetermined focused position when the annular member is maintained clamped at this position.

Abstract: In the disclosed diaphragm device, an electromagnetic unit is composed of two opposing sets of circularly arranged magnets poled so that opposing surfaces have the same polarity, a rotary member carrying an electromagnetic coil that moves the rotary member in response to current therethrough and the field of the magnets, and diaphragm blades which are positioned between the magnet members and the rotary member and pivoted to close the aperture in response to rotation of the rotary member in one direction. When the rotary member is rotating in the closing direction, stopping means respond to an input signal and stop movement of the diaphragm blades at a particular aperture value.

Abstract: An adjusting mechanism for the mechanical mounting arrangement of a lens assembly operative to enable lens components to be axially adjusted for appropriate positioning during the assembly operation of the device. A guide member is provided for guiding a lens mounting member along a linear guide slot in a cylindrical member, the guide member engaging with the guide slot and connected to the lens mounting member. An eccentric adjusting device operates to adjust the axial position of the movable lens mounting member, the structure and arrangement of the eccentric device being such that after appropriate positioning of the movable lens group has been performed, the assembly may be firmly locked in the adjusted position without the danger of inadvertent misalignment.

Abstract: The invention provides a photographing apparatus having a focusing system for controlling the movement of a focusing lens. The output of the signal from the focusing system is so controlled that the continuous operation of the focusing system is interrupted in response to the operation of an imaging device such as a single reflex camera, a video camera, etc.

Abstract: An interchangeable lens assembly comprises a phototaking lens system for imaging an object, an automatic focusing device for detecting the object distance and outputting a signal for moving the lens system to an in-focus position, and a focus adjusting member for moving the lens system along the optical axis. The automatic focusing device includes a distance detector, a motor for generating a drive force to drive the lens system in accordance with an output signal from the distance detector, and a transmission for transmitting the drive force. The focus adjusting member is connected to the lens system and to the transmission, and the lens system is moved in accordance with either the manual rotation of a manually operated portion of the focus adjusting member about the optical axis or by the drive force from the motor through the transmission.

Abstract: A clamping device for a camera accessory such as a hood includes a generally tubular attachment portion forming a part of the accessory for attachment to a camera lens mount or a pre-assembled, telescoping hood arranged on a lens mount. A number of projecting members extend radially inwardly from the inner circumference of the attachment portion to contact the outer periphery of the lens mount or pre-assembled hood. An engagement member extends through the attachment portion and is urged by a spring to contact the outer periphery of the lens mount or pre-assembled hood so that the engagement member, together with the projecting members, operate to fix the accessory on the lens mount or pre-assembled hood.

Abstract: In the disclosed diaphragm device, an electromagnetic unit is composed of two opposing sets of circularly arranged magnets poled so that opposing surfaces have the same polarity, a rotary member carrying an electromagnetic coil that moves the rotary member in response to current therethrough and the field of the magnets, and diaphragm blades which are positioned between the magnet members and the rotary member and pivoted to close the aperture in response to rotation of the rotary member in one direction. When the rotary member is rotating in the closing direction, stopping means respond to an input signal and stop movement of the diaphragm blades at a particular aperture value.

Abstract: An extension tube or barrel which can be connected between a camera body and an interchangeable lens assembly includes a tubular body arranged to be coupled at one end to the camera body and at its other end to the lens assembly. A member within the tubular body is provided for engaging a diaphragm actuating member in the lens assembly in response to movement of an actuating member in the camera body. The extension tube also includes an arrangement for interchanging the positional relationship between the actuating member in the lens assembly and the member in the extension tube when the tubular body is either coupled to or uncoupled from the camera body. Thus, mechanical interference between the actuating member in the camera body and the corresponding member in the extension tube is avoided when the tubular body is placed against the lens mount of the camera and rotated during coupling or uncoupling of the extension tube.