Abstract: A camera is capable of using a film cartridge bearing code indicia indicating the film speed of the film contained in the cartridge. The camera comprises first means for detecting the film speed from the code indicia of the film cartridge loaded in the camera and generating a first corresponding signal, and second means for manually setting the film speed and generating a second corresponding signal. The camera further comprises discriminator means connected to the first and second means and adapted to generate an output signal upon detection that neither the first nor the second signal is generated, and means for generating an alarm in response to the output signal of the discriminator means.

Abstract: A film sensitivity setting device for camera is provided with a circuit board comprising a first information unit with a conductor pattern which detects the film sensitivity information signal from a film cartridge having such signal and corresponds to the information signal of the manually set film sensitivity, and a second information unit with a conductor pattern for transmitting the detected information signal, wherein the exposure of the film is controlled according to the information signal obtained by electrical contact with the conductor pattern of either the first or the second information unit.

Abstract: A film feed control apparatus generates an output signal for instructing the rewinding of the film when a wind operation for a frame of a film is stopped before it is completed and the number of exposed frames has exceeded a nominal number of exposures. The film feed control apparatus stops the power supply to a wind motor when the wind operation is stopped before the number of exposed frames reaches the nominal number of exposures.

Abstract: Apparatus for detecting code indicia containing electrically conductive contacts and being indicative of one or more characteristics of the film contained in the film cartridge, comprises a wall member forming a chamber for receiving the cartridge. The wall member has through-holes provided at positions opposed to the code indicia. The apparatus is further provided with a circuit substrate disposed on the side opposite to the chamber and opposed to the wall member and having thereon an electric circuit means for reading the characteristics of the film. The circuit substrate has electric terminals. The apparatus further includes electrically conductive contact members being slide-movably inserted into the respective through-holes on the wall member. Each of the contact members has two ends one of which contacts with one of the code indicia and the other end contacts with one of the electric terminals.

Abstract: A camera is provided with a detecting means provided with detecting contacts capable of positively detecting an information code on a film cartridge loaded in a film chamber and so arranged that they will not adversely affect the stability of the film cartridge loaded in the film chamber.

Abstract: A camera into which a magazine containing a film therein and provided with means indicative of information concerning the film speed of the film can be loaded includes a device for detecting the film speed of the film on the basis of the information when the magazine is loaded into the camera and producing a first film speed signal indicative of the detected film speed, a device for manually setting the film speed of the film and producing a second film speed signal indicative of the set film speed of the film, a device for detecting the difference between the film speeds of the film indicated by the first and second film speed signals and producing a warning signal, a device for drawing out the film from the loaded magazine, and a device for hindering the production of the warning signal in response to the draw-out of a predetermined amount of film from the magazine.

Abstract: In an interchangeable lens having a mount mountable on a camera incuding an electric circuit associated with exposure control and a displaceable actuating member for correcting the electric circuit so as to be accommodated to the focal length of the interchangeable lens mounted, a signal member is provided projectedly from one end of the mount and engageable with the actuating member so as to cause said displacement when the interchangeable lens is mounted on the camera. The signal member has an engaging end portion engageable with the actuating member. The engaging end portion lies at a position determined relative to the mount for displacing the actuating member by an amount related to the logarithm of the focal length of the interchangeable lens.

Abstract: In an intermediate lens barrel mountable between an interchangeable lens having on the mount thereof means for generating a minimum F-number signal and a camera having means for detecting the signal on the mount thereof on which the interchangeable lens is mountable and including a circuit for receiving as inputs the detected signal and an output based on the light passed through the interchangeable lens and effecting an exposure operation, there is provided means capable of being coupled to each of the signal generating means and the detecting means during said mounting. The transmitting means includes correcting means for shifting the signal obtained from the signal generating means by an amount corresponding to the difference of the minimum F-number obtained as the result of the coupling of the interchangeable lens and the intermediate lens barrel from the minimum F-number of the interchangeable lens and transmitting the signal to the detecting means.

Abstract: An intermediate lens tube to be mounted between an interchangeable lens and a camera body is provided with means for transmitting an information signal from the interchangeable lens to the camera body. Said information transmission means includes correction means for transmitting a corrected information signal to the camera body only when vignetting takes place in the intermediate lens tube.

Abstract: An auxiliary lens capable of being mounted between an interchangeable lens having on the mount thereof means for generating a minimum F-number signal and a camera having means for detecting said signal on a mount to which the interchangeable lens may be mounted and including a circuit receiving as input the detected signal and an output based on the light passed through the interchangeable lens to effect an exposure operation. The auxiliary lens includes an optical system for changing the focal length of the interchangeable lens. The auxiliary lens is provided with transmitting means capable of being coupled to each of the signal generating means and the detecting means during said mounting and adapted to transmit the signal to the camera by said coupling, and a signal member having information corresponding to a variation in the F-number caused by the change of said focal length and capable of transmitting the information to the camera during said mounting.

Abstract: A large aperture ratio interchangeable lens for a single lens reflex camera comprises a lens body, a preset aperture ring provided for rotation with respect to the lens body, a first signal member operatively associated with the preset aperture ring to transmit a corrected difference signal (f-f.sub.O -.DELTA.f) to the camera body, and a second signal member for transmitting a corrected open value signal (f.sub.O +.DELTA.f) to the camera body.

Abstract: This invention relates particularly to a phototaking lens having at least a shutter speed priority automatic exposure system. The lens has a mount engageable with a mount of a camera body, which has a signal member operable when the lens is mounted and control means for making a caution and/or for stopping camera operation in response to an output of the signal member. The lens is further equipped with means for presenting the operation of the signal member, this means being disposed on the lens mount facing the signal member as the mount of the lens is engaged with the mount of the camera body. The signal member includes a retractable signal pin projected from the mount of the camera body and the preventing means includes a recess on the mount of the lens which is acceptable to the signal pin.

Abstract: An improved photographing mode switching mechanism is disclosed which is adapted for a camera provided with a switchover member movable between a first position in which non-diaphragm control mode is selected and a second position in which diaphragm control mode is selected. The improved photographing mode switching mechanism comprises a detection member for detecting the position of preset diaphragm ring of the lens tube and a control means for controlling the switchover member and the detection member. When the detection member detects that the diaphragm ring is in a position for the minimum aperture, the control means allows the switchover member to stay in the second position.

Abstract: A finder screen-supporting apparatus for a single-lens reflex camera with an interchangeable focusing screen, comprises a screen support frame attachable to the camera body and directly supporting the focusing screen by four ends thereof, and a spring member pressing the focusing screen to the focal position and fixing said screen in said position upon attaching said frame to said camera body.

Abstract: An exposure indicating device for a single lens reflex camera having a built-in TTL exposure meter to indicate photographic information on photographic information members within a view finder with the help of external light, and having an eye-piece shutter to intercept the view finder optical system at its eye-piece section, wherein there are further provided a light emitting element at a position at which the photographic information members can be illuminated for indication within the view finder, and at which the light emitting element is able to emit light outside the camera body; and change-over means which is interlocked with opening and closing of the eye-piece shutter to connect the light emitting element to a power source through switching means operable from outside, when the eye-piece shutter is open, and to connect the light emitting element to the power source through an exposure measurement circuit of the TTL exposure meter, when the eye-piece shutter is closed.

Abstract: In a single lens reflex camera, an aperture interlocking device wherein a pantograph mechanism has one lever biased in one direction within a viewfinder detachable with respect to the body of the camera, is connected to the engaging portion of the aperture ring of the picture-taking lens during the mounting of the viewfinder to the camera body so that the aperture information of the picture-taking lens is transmitted to an exposure control device by displacement of the pantograph mechanism, is provided with first guide means for guiding the pantograph mechanism so that a pin on the one lever of the pantograph mechanism is rotatable about the optical axis of the picture-taking lens, an engaging lever engageable with the engaging portion of the aperture ring and supported for rotation on the one lever of the pantograph mechanism, and second guide means for guiding the engaging lever so that the engaging lever is rotated about the optical axis of the picture-taking lens.

Abstract: In an exposure indicator device in a single lens reflex camera with a TTL exposure meter contained therein which comprises shutter means extraneously operable for displacement between a position in which it closes the opening of an eyepiece mask to intercept light passed through the finder eyepiece portion into the interior of the finder and a position in which it is retracted from the first-named position, first indicator means for effecting exposure indication within the view field of the finder, and second indicator means for effecting exposure indication outside the view field of the finder, change-over means is operatively associated with the shutter means to cause only the first indicator means to effect the exposure indication when the shutter means is in the retracted position and to cause only the second indicator means to effect the exposure indication when the shutter means is in the light-intercepting position.

Abstract: In a single lens reflex camera, an aperture interlocking device wherein a pantograph mechanism has one lever biased in one direction within a viewfinder detachable with respect to the body of the camera, is connected to the engaging portion of the aperture ring of the picture-taking lens during the mounting of the viewfinder to the camera body so that the aperture information of the picture-taking lens is transmitted to an exposure control device by displacement of the pantograph mechanism, is provided with first guide means for guiding the pantograph mechanism so that a pin on the one lever of the pantograph mechanism is rotatable about the optical axis of the picture-taking lens, an engaging lever engageable with the engaging portion of the aperture ring and supported for rotation on the one lever of the pantograph mechanism, and second guide means for guiding the engaging lever so that the engaging lever is rotated about the optical axis of the picture-taking lens.