Abstract: A medical apparatus has a C-arm which carries a radiation transmitter, and which is adjustably held by a mount so as to be movable along the circumference of the C-arm. The mount engages guideways which are provided at a rear side of the C-arm. The C-arm is in the form of a hollow, profiled part having a substantially U-shaped cross-section. The guideways are respectively disposed at the insides of the legs of the U-shaped cross-section. The C-arm has an interior channel therein with a rectangular cross-section, which is adapted for accepting electrical leads or supply lines for the radiation transmitter. The channel is laterally adjacent one leg of the U-shaped cross-section.

Abstract: An x-ray diagnostics installation for producing x-ray images has an x-ray image intensifier and a detector for measuring the average image brightness in a dominant region of the output screen of the x-ray image intensifier, and a gating unit with which the size and position of the dominant region can be varied. The gating unit is in the form of a tape roll of opaque material having a number of differently sized and shaped openings therein, corresponding to different desired measuring fields. A large number of differing dominant regions can thereby be selected by means of a unit which occupies a small space.

Abstract: A light distributor for an x-ray diagnostics installation has mirror-symmetrically disposed sets of light exit ports at a housing, which are adapted for connection to various different image recording components. Inside the housing, a mirror system is provided which can be arranged in a first position or a second position. When the system is arranged in the first position, light is directed from an input port of the light distributor to a first of the sets of light exit ports in the housing. When the mirror system is arranged in the second position, light from the input port is directed to a second of the sets of light exit ports. The mirror system can be changed between the first and second positions by a simple manual operation, using the same mirrors and the same mirror mounts, which are interchangeably accepted in a single set of mounting locations in the housing.

Abstract: A switch mechanism for an image intensifier hood in an x-ray diagnostics system is connected to a motor for moving the x-ray image intensifier toward and away from an examination subject. If the hood inadvertently comes into contact with the examination subject or a technician, the hood is displaced thereby actuating the switch mechanism and disengaging the motor to stop movement of the x-ray image intensifier, thereby avoiding injury to the examination subject and technician and avoiding damage to the x-ray image intensifier. The switch mechanism is constructed such that actuation thereof occurs upon the presence of forces acting on the hood in the direction of the luminescent screen surface or a direction perpendicular thereto, and each intermediate direction.