Abstract: A camera having a barrier according to the present invention includes a barrier unit in a space between a front main body and a front metal cover serving as an exterior member. Rotation of a barrier driving motor is transmitted to a rotary shaft member passing through the front main body, thereby allowing opening/closing actions of the lens barrier between a protection position for a photographing lens and a lens-barrier retracted position. The front main body is sealed waterproof by an O-ring provided to the outer circumferential surface of the rotary shaft member. With the lens barrel of the camera, rotation of a rotary moving frame is effectively transmitted to a cam frame through a cam follower fit to a linear-action groove, using a circumferential groove and the linear-action groove of a bayonet mechanism.

Abstract: A camera having a barrier according to the present invention includes a barrier unit in a space between a front main body and a front metal cover serving as an exterior member. Rotation of a barrier driving motor is transmitted to a rotary shaft member passing through the front main body, thereby allowing opening/closing actions of the lens barrier between a protection position for a photographing lens and a lens-barrier retracted position. The front main body is sealed waterproof by an O-ring provided to the outer circumferential surface of the rotary shaft member. With the lens barrel of the camera, rotation of a rotary moving frame is effectively transmitted to a cam frame through a cam follower fit to a linear-action groove, using a circumferential groove and the linear-action groove of a bayonet mechanism.

Abstract: A semiconductor radiation sensor arrangement for an automatic X-ray exposure control apparatus disposed in front of an X-ray film to be exposed to X-rays. A semiconductor radiation sensor is set in a mount. The mount is bored with a tapering penetrating hole and securely engaged with a hole penetrating a substrate. The peripheral walls of the mount and that of the penetrating hole of the substrate are tapered in cross section in the similar form. The semiconductor radiation sensor is fixed in the penetrating hole of the mount and has a sufficiently small thickness to cause X-rays to be attenuated to a less extent than 800 microns of aluminum equivalent thickness. Leads are formed of an aluminum layer with a smaller thickness than 80 microns and connected to the electrodes of the semiconductor radiation sensor. At least one scattered X-ray eliminating grid is disposed in parallel with the substrate and the semiconductor radiation sensor.

Abstract: An X-ray cine radiography apparatus comprising: an X-ray tube for radiating X-rays toward an object under examination; an image intensifier for converting the X-rays transmitted through the object into a visual image; a cine camera for picking up the visual image; a photomultiplier for detecting a brightness of the visual image to produce an electric signal; a first potentiometer for setting an upper limit tube voltage of said X-ray tube; a second potentiometer for detecting a signal corresponding to an actual tube voltage of said X-ray tube; a comparator for comparing the output signal of said second potentiometer with that of said first potentiometer and for producing an enabling signal when the former recited output signal exceeds the latter recited output signal; means for controlling quantity of light of the visual image picked up by said cine camera in accordance with the enabling signal of said comparator; and means for adjusting the actual tube voltage in response to the output signal of said controll