Abstract: A lens holding frame holding a lens having a circular outer diameter includes a first holding member forming an inscribed circle corresponding to the outer circumference of the lens and a second holding member forming a larger inscribed circle than the inscribed circle formed by the first holding member. The first holding member comprises three projections and they are located at an equal distance in the circumferential direction of the lens holding frame. Similarly, the second holding member also comprises three projections and they are located at an equal distance in the circumferential direction of the lens holding frame. In this case, the projections forming the first holding member and the projections forming the second holding member are located alternately on the inner diameter of the lens holding frame in the circumferential direction respectively.

Abstract: A support structure is provided wherein a fitting backlash is provided between a lens and a retaining frame to enable positioning of the lens while restraining degradation of optical performance even if the lens shifts. The lens has two opposed optical characteristic surfaces. A first one of the optical characteristic surfaces is formed of a spherical surface, while the other has a spherical portion that is annularly formed in a periphery thereof and that has the same center as the spherical surface of the first one of the optical characteristic surfaces. When abutted on an inner circumferential end of the retaining frame, the spherical portion is correctly aligned and supported on an optical axis of an optical system (see FIG. 2).

Abstract: A lens barrel (lens frame structure) using a cam mechanism with a cam follower is provided in which deviation of engagement of a frame member at an engaging part of the cam-follower is less likely to happen. A cam ring and a lens holding frame of the lens barrel are connected through the cam-follower, with a first cam groove running obliquely to an optical axis and a second cam groove running along the periphery direction of the optical axis. The second cam groove comprises an oblique cam plane and a parallel wall plane, and the cam-follower has a conical surface in sliding contact with the cam plane and a circular ring part in sliding contact with the parallel wall plane. The circular ring part digs into the parallel wall plane and deviation of the cam ring is prevented, if the cam ring comes to be distorted by applying careless stress to the cam follower.

Abstract: A lens barrel (lens frame structure) using a cam mechanism with a cam follower presents a lens barrel where deviation of engagement of a frame member at the engaging part of a cam-follower is less likely to happen. A cam ring and a lens holding frame constituting the lens barrel of the present invention are connected through a cam-follower, the first cam groove running obliquely to an optical axis and the second cam groove along the periphery direction of the optical axis. The second cam groove comprises an oblique cam plane and the parallel wall plane, and the cam-follower has a conical surface in contacted with a sliding cam plane and a circular ring part contacted with sliding with a parallel wall plane. The circular ring part digs into the parallel wall part and deviation of a can ring is prevented, if cam ring comes to be distorted by applying careless stress to a cam follower.

Abstract: In a lens barrel, a group-2 lens frame, which is movable forwardly and backwardly, is fit into an inner peripheral portion of an M-cam frame which is rotatably supported. A cam groove, into which a cam follower fits, is provided at the M-cam frame. A shaft hole, into which a shaft portion of the cam follower is press-fit and fixed, is provided at the group-2 lens frame. Two edge portions are formed at the shaft portion. Two conical slide faces are provided at a portion which slides at the cam groove of the cam follower. The two edge portions are provided at end portions of the slide faces. When the cam follower attempts to tilt, the edge portions of the shaft portion bite-into a cam face, and prevent a fit-together state of the shaft portion from coming out of place. Further, when an external force acts on the cam follower, the edge portions of the conical slide faces bite into the cam groove such that a fit-together state of the cam follower is prevented from coming out of place.

Abstract: A lens is formed in a generally rectangular shape, and a reflection-preventing portion capable of preventing reflection of harmful rays is provided on at least one edge plane forming at least a portion of the perimeter of the lens, so that the lens is capable of suppressing deterioration of the quality of images including object images formed by a photographic lens system, in order to obtain better photographic images.

Abstract: In a lens barrel of the present invention, a M-cam frame is engaged with a rotary frame and movable frame so that the M-cam frame can rotate and advance or withdraw freely. A second group-of-lenses frame is engaged with the M-cam frame. A first cam follower is fixed to the M-cam frame with an edged shaft thereof press-fitted to the M-cam frame. A second cam follower having an edged slider surface is fixed to the second group-of-lenses frame. The slider surface of the first cam follower is engaged with a cam groove formed in the rotary frame so that the first cam follower can slide freely. The slider surface of the second cam follower is engaged with a cam groove formed in the M-cam frame so that the second cam follower can slide freely. The shaft of the first cam follower which is press-fitted will hardly come out owing to the edge thereof. Moreover, the second cam follower will hardly come off from the cam groove owing to the edge thereof.

Abstract: A lens holding structure is incorporated in an optical system, such as the photographing optical system of a camera. The lens holding structure has a holding member (i.e., a lens frame) for holding a non-circular lens included among the lenses of the photographing optical system. The non-circular lens has an arcuate outline portion and a linear portion. The holding member holds the non-circular lens by supporting it at at least three points on the arcuate outline portion without touching the linear portion of the lens. The lens holding structure is simple and enables easy and accurate assembly of the optical system of the camera.

Abstract: A camera optical system has a photographic optical system and a finder optical system. The photographic optical system has a photographic lens section that receives an optical image from a subject to be photographed and forms an image on a film. The finder optical system has a nonphotographic lens provided integrally with the photographic lens section of the photographic optical system.

Abstract: A sealing device has a sealing assembly disposed between a pair of a fixed frame and a first moving frame that relatively circularly move and rectilinearly move. The sealing assembly is fixed by bonding to the fixed frame. Two inclined fins of the sealing assembly are in slidable contact with the outer peripheral surface of the first moving frame. The fins provide a reliable light shielding, waterproofing, drip-proofing, or dust-proofing effect between the fixed frame and the first moving frame. The gap between the first moving frame and a second moving frame and the gap between the second moving frame and a frame are also sealed by the sealing assembly in the same manner. The sealing device permits reliable light shielding, waterproofing, drip-proofing, or dust-proofing, and also enables a lens frame to be made smaller at the same time.

Abstract: A lens barrel is provided with: first and second lens frames which are adapted to be able to make a relative displacement therebetween and are adapted so that an inner peripheral portion of one of the first and second lens frames overlaps with an outer peripheral portion of the other lens frame in a used state; a light shielding portion, which is provided at one end portion of the first lens frame, for blocking light which is incident from the end portion in the used state; and a pressure-contact light shield member that is provided at a place which is nearer to an other end portion of the first lens frame than the light shielding portion provided at the one end portion thereof and that is adapted to be elastically deformed by being pressure-contacted to the outer peripheral portion of the second lens frame, thereby blocking light transmitted by the light shielding portion provided at the one end portion of the first lens frame.

Abstract: In a lens barrel, a flare diaphragm is disposed on an optical path of lenses or in the vicinity thereof such that the flare diaphragm can advance into and retreat from the optical path for cutting deleterious light corresponding to the lenses moving in the direction of the optical axis. This lens barrel can reliably cut deleterious light flux in a simple structure.

Abstract: A lens barrel with a stationary frame fixed relative to a camera body; a flare diaphragm movable in a direction of an optical axis for cutting off harmful incident light; an urging spring urging the flare diaphragm in the direction of the optical axis; a third group frame including a protruding portion which is driven into abutting contact with the flare diaphragm to restrict a position of the flare diaphragm in the direction of the optical axis, the third group frame being moved in the direction of the optical axis; and, a supporting shaft rigidly positioned on the stationary frame. The supporting shaft guides the movable flare diaphragm in the direction of the optical axis, while being snugly fitted to the flare diaphragm. In addition, the supporting shaft includes a stepped front portion for restricting such movement of the flare diaphragm to a predetermined position.

Abstract: A lens barrel with a cam mechanism, manufactured by molding plastic, comprising a plurality of cams having a plurality of parting lines, for lens driving, and a plurality of cam followers that are engaged with the plurality of cam faces of the respective cams. The plurality of parting lines are arranged on the plurality of cam followers in a manner that the positions of the parting lines relative to the respective cam followers are set to be different from each other. In the driving of lenses, no two cam followers are simultaneously positioned at their respective parting lines so that the lenses may be free from the effect of a step at each parting line. Thus, the deviation of the position of each lens is minimized.

Abstract: An imaging lens system comprises an axial support section, such as a support hole, a notch, and a guide sleeve, integrally formed with a lens and arranged generally within the maximum diameter of the lens but outside an effective area of the lens through which an imaging light is transmitted. The imaging lens system also comprises a guide shaft that slidably supports the axial support section for a advancing and recessing motion of the lens. The area outside the imaging light transmitting area is effectively used. A small component count, compact and low-cost design is implemented in the imaging lens system.

Abstract: In a camera using a film cartridge that holds a film with a load exerted on the film in the direction of the width of the film, a time counting block for time counting at each predetermined action of the camera, a time information memory block for storing the time from the time counting block, a film feed condition determining block for determining the condition of film feed, a time information determining block for computing a film hold time based on the latest time counted by the time counting block and the time stored in the time information memory block, and a camera setting update block for updating the camera setting according to the hold time to compensate for film curling.

Abstract: A camera loading chamber into which a film cartridge is loaded by dropping the cartridge into an opening of the camera against the urging force of an urging member. The film cartridge is held within the loading chamber by a trapdoor which is closed over the loaded cartridge and held in its closed position by a locking mechanism. Upon releasing the locking mechanism, the cartridge is urged toward the exterior of the camera and causes the trapdoor to open under the urging force of the urging member. A stopping member causes the trapdoor to stop at a position between its closed position and its fully open position so that the cartridge is prevented from jumping out of the cartridge loading chamber.

Abstract: The present invention provides a camera enabling selection of a normal photography mode in which an object image formed by a lens array is printed as it is or in a proportional size, or a trimming photography mode in which part of the image alone is enlarged and printed.The camera includes masks formed with translucent members and used to confirm the object range for the trimming photography mode in the view finder, and a device for positioning the masks in the view finder for trimming photography.

Abstract: A camera comprises: a photographing lens; a viewfinder lens lying behind the photographing lens so that an object to be photographed can be viewed; a first reflector mirror capable of being displaced between a first position, at which the first reflector mirror intervenes between the photographing lens and viewfinder lens so that light emanating from the photographing lens is reflected horizontally substantially at 90.degree., and a second position at which the first reflector mirror has retracted from between the photographing lens and viewfinder lens; a second reflector mirror lying by the side of the first reflector mirror so that the light emanated from the photographing lens and reflected from the first reflector mirror is reflected vertically substantially at 90.degree.

Abstract: A Patrone according to the present invention comprises a spool that winds film in the form of a roll between two flanges thereof, and a Patrone body for storing said spool so that the spool can rotate freely. The spool is made of a shading material. The distal part of the film is provided with a leader whose width is equal to or smaller than the dimension between the two flanges and which winds round the outer circumference of film wound about the spool by at least one turn. The leader may also be formed of or include a shading material.