Abstract: The present invention discloses a cover for an x-ray cassette which has a sleeve made of radiolucent material to receive an x-ray cassette. A foam pad is attached to the sleeve and aligned such that the foam pad covers the x-ray cassette. The foam pad is made of radiolucent material. The sleeve is made from a first sheet and second sheet of radiolucent material attached on three sides, which create a slot and a sleeve.

Abstract: An improved sterile container device, having a tear-away throat, which includes walls defining a cavity having a closed end and an open throat, a first cuff connected to the walls adjacent to the open throat, a shield and a second cuff in overlying relation to the first cuff and upper portions of the walls adapted to protect same from contamination by a non-sterile article being inserted into the cavity, and a sleeve for removing the shield from the cavity and for cooperatively effecting a separation of the device into a sterile portion containing the contaminated article and a discard portion. A pressure sensitive adhesive provides a sealing arrangement for sealing the non-sterile article in the sterile portion.

Abstract: In connection with X-ray or like examination there is used a cassette holder arrangement which is carried by a frame structure (7) by means of pivotal arms (4) which are capable of being swung in the horizontal plane, such as to adjust the position of the cassette in the vertical direction. The arrangement enables pictures to be taken of a sitting patient in mutually perpendicular directions, with the aid of a radiation source (2). The cassette holder (3) can be swung between the exposure positions in a circuit path around the sitting patient, by activation of one of the arms (4). To this end there can be used a parallel linkage (11) which is operative to guide the cassette holder during this pivotal movement. the cassette holder is fixated relative to one of the arms (4), by means of a locking device (8), which is released when wishing to pivot the cassette holder. The invention also relates to a cassette holder arrangement of the aforedescribed kind.

Abstract: An X-ray apparatus includes a moving carriage having two levers hinged and designed to move equally and in opposite directions by a gear system. The movements of the levers are guided by at least one groove formed in a supporting plate, with a peg fixed to the lever co-operating with the groove. The groove includes at least two spaced-apart rectilinear portions, each corresponding to a different size of cartridge, thereby enabling the cartridge to be moved on the supporting plate.

Abstract: An x-ray film positioning device wherein the film holder and x-ray beam alignment rod can rotate together while the biteblock remains stationary. Such rotation is accomplished by means of an axle placed through the body of the biteblock, or through tubes attached to the biteblock, and attaching the film holder to one end of an extension bar and attaching the other end of the extension bar to one end of the axle, and further attaching the beam alignment rod to the other end of the axle. By the configuration of this assembly, a predetermined relationship of the film to the x-ray beam e.g. parallel, can be maintained with all angles of rotation. Simultaneously, the biteblock remains stationary in a flat, occlusally parallel position, held securely between the upper and lower teeth. This rotational concept is particularly helpful, but not limited to, film holder biteblock arrangements which are laterally off-set one to the other when viewed from the x-ray source.

Abstract: The present invention is especially suited for tomographic X-ray studies wherein dozens of exposures are required. A film cassette spacer having selected dimensions and having selected markings thereon is placed adjacent to the film cassette on a mechanically centering bucky tray in an X-ray machine. By use of the collimating means in the X-ray head, the number of exposures on the film can be maximized but still maintaining quality exposures for reading.

Abstract: The invention relates to a X-ray examination unit, comprising a stand on which is vertically movable a bracket with a moving grid means and a X-ray tube. In order to permit a large number of photographing possibilities on a standing, sitting or lying patient from different directions, said bracket is also horizontally movable, said moving grid means at a lateral end of said bracket is pivotable about a vertical axis, said X-ray tube is held on one end of a substantially C-shaped support arm, whose other end is located on said moving grid means and is fixed in such a way that said X-ray tube, together with said moving grid means, is pivotable about said vertical axis and said moving grid means is additionally rotatable about a horizontal axis.

Abstract: A convenience-enhancing improvement upon a known dental film packet (FP) having sensitized film and protective opaque sheets (10 and 12, 14) enclosed by an openable light-tight envelope (16), one of whose opaque sheets (12c) covers substantially all of the film sheet (10) when both (12c and 10) are partially withdrawn after its envelope (16) has been opened, rendering the film sheet (10) inconvenient to grasp and remove alone. In a first embodiment, the improvement comprises shortening said one opaque sheet (12c') so that it (12c') remains sufficiently protective without covering a graspable end portion (10L') of the film sheet (10').

Abstract: Methods and apparatus for determining film processor performance. Films for use in radiographic imaging, adapted to evaluate performance of a film processor which develops an image of a structure of interest on the films are provided. The films have exposable areas for radiographically imaging the structure of interest, and test means integrally located on the exposable areas for determining the performance of the processor which develops the radiographic image on the film.

Abstract: Cassette centering device for an X-ray cassette loading and unloading device using two parallelly movable guides engageable with the side edges of the cassette, the guides being movable by a lever arrangement driven by a motor, the lever arrangement including a link having two telescoping parts and biasing means constituting force absorbing means for cushioning the engagement of the guides with the cassette and compensating for motor overdrive.

Abstract: An X-ray radiographing apparatus includes a power assist device for causing a driving mechanism to generate force for assisting that force which is added to a handle assembly of a spot film device in a direction, so that the spot film device is moved by the sum of both forces in the direction. The movement of the handle assembly is detected by a pressure sensor, so that the detecting signal responsive to the movement is outputted to a control circuit. A driving signal responsive to the detecting signal is supplied from the circuit to the driving mechanism, so that the spot film device is moved in the direction. A component of the weight of the handle assembly is balanced with that of a counter weight, whereby the pressure sensor is prevented from being wrongly operated by the component of the weight of the handle assembly. The width of blind zone of the pressure sensor can be made narrower. The response speed of the spot film device can be made narrower.

Abstract: An X-ray examination apparatus includes a device for positioning an X-ray film changer with respect to an image intensifier away from a position in front of the image intensifier for producing X-ray images to a position on a side of the image intensifier when not in use. The device combines a rotational and shifting movement so that the film changer can be positioned on the side of the image intensifier very close to the same without impeding access to a patient.

Abstract: In a device for holding down the lower cassette portion (19a) of an X-ray film cassette which is located in a cassette unloading and reloading apparatus, a hold-down lever (20, 21) is mounted to each of two parallely guided bars (10, 12) movable towards and away from each other respectively, said hold-down lever being pivotable into, and out of the transport path of the X-ray film cassette to accurately position said cassette. Each hold-down lever (20, 21) comprises a control arm (20a, 21a) resting against each of the two side walls (19d, 19e) of the upper cassette portion (19c). Since the control arms (20a, 21a) are upwardly inclined such that they form control surfaces facing the side walls (19d, 19e) of the upper cassette portion (19c), the hold-down levers (20, 21) are held in engagement with the lower cassette portion (19a) when the upper cassette portion (19c) is in its open position and are disengaged from the lower cassette portion (19a) when the upper cassette portion (19c) is in its closed position.

Abstract: An X-ray imaging system for obtaining a photographic image of the X-ray transmissivity of a body is disclosed. A source of X-rays is directable at the body, and an X-ray imaging subsystem is provided for receiving a pattern of X-rays transmitted through the body, including, in combination: a first X-ray-sensitive screen for converting the pattern of X-rays to a first pattern of light; a light-sensitive film adjacent the first X-ray sensitive screen for receiving the first pattern of light; a second X-ray sensitive screen for also converting the pattern of X-rays to the first pattern of light; an array of light detecting devices positioned to receive the first pattern of light from the second X-ray sensitive screen; means for storing electronic representations of the outputs of the array of light detecting devices; and light generating means responsive to the stored electronic representations for generating a second pattern of light which is directed at and received by the light-sensitive film.

Abstract: A fluid controlled counterbalance and power-assist system for use in a diagnostic x-ray imaging system includes a first member and a second member movably mounted to said first member. A slave actuator including a reciprocal piston is selectively coupled between the first and second members. Fluid coupling ports are located on each end of the cylinder for coupling working fluid to either side of the piston. First and second master actuators each including a cylinder are located remote from the imaging system. Each master actuator has fluid coupling ports selectively located on each end of its cylinder for coupling working fluid to one side of the cylinder and control fluid to the other side. Working fluid connection lines connect one end of the slave actuator to one end of the first master actuator and connect the opposite end of the slave actuator to the second master actuator for providing working fluid flow between said actuators.

Abstract: An X-ray cassette holding which is capable of being sterilized for use in an Operating Room includes a hinged cover and an opening for receiving a non-sterile X-ray cassette. A receiver portion into which the cassette is inserted is spaced from the interior of the side and end walls of a pivoting cover to isolate the exterior of the cassette holder from contamination by virtue of the insertion of a contaminated cassette into the holder. Seals may be provided to seal the cover edges and portions of the receiver edges from the exterior of the holder when the cover is in a closed position. When the cover is opened, the cassette may be removed, and a new cassette inserted without contaminating the exterior sterile surfaces of the holder.

Abstract: A holder for radiographic film fits between the jaws; the patient secures the holder steady by biting down thereon. The holder is U-shaped to provide space for root canal files which otherwise prevent the patient from biting down on conventional film holders. The holder accommodates placement of the film in horizontal or vertical direction and also for such placement while filming either jaw. Separate U-shaped holders may be used for anterior and posterior positions and separate posterior holders for the left and right jaws. By inverting the right lower posterior holder, it may be used on the upper left.

Abstract: A method and system are disclosed for producing a photographic image of an X-ray pattern, including the following steps: converting the X-ray pattern to a first pattern of light; exposing a photographic film to said first pattern of light; detecting the light at elemental regions of the first pattern; generating a second pattern of light in a pattern which depends on the detected light; and exposing the photographic film to the second pattern of light. The generating of the second pattern of light includes generating light from a one-dimensional array of light emitters, and moving the array with respect to the photographic film. The disclosed invention provides improvement on the standard radiographic method in the following ways: (1) The recorded film contrast in low X-ray exposure regions that ordinarily would have been recorded in under-exposed regions on a film's characteristic curve will be increased significantly.

Abstract: A system and method is disclosed for minimizing residual vibration of a radiographic system due to rapid movement of a radiographic film cassette between a park and expose position. The cassette is moved by a servo system including a servo motor which is responsive to a voltage input waveform to drive the cassette. A waveform is chosen for the voltage input such that no inpulse derivatives appear until the waveform has been diferentiated at least three times. The primary natural resonant frequency of the system is determined and noted. The duration of the selected input waveform is adjusted such that the frequency spectrum of the adjusted input waveform defines a relative null which approximately coincides with the primary resonant frequency. The amplitude of the voltage input waveform is then further adjusted as a function of the distance to be traveled by the cassette between the park and expose positions.

Abstract: A bite wing x-ray film holder includes at least one packet of liquid food product that is adapted to release that food product into the patient's mouth during the x-ray procedure.

Abstract: An energy detecting cassette for detection of electromagnetic energy (X-ray, magnetic resonance imaging (MRI), etc), sound energy, and other detectable forms of energy used for examination of the interior of objects consists of a flat box for holding an image fixing medium having an edge wall portion contoured to fit the surface of an object adjacent or next to the portion of the object to be subjected to detectable energy.

Abstract: A size sensing X-ray cassette tray having a pair of longitudinally spaced opposing front and back cassette clamps linked together by a center pivoted arm and link members for unison movement. A side sensing arm is connected by an elongatable link member to a pivoted leg which is actuated by a probe of an X-ray system. Arcuate potentiometers are coupled to the pivoted arm and the side sensing arm so as to provide electric signals corresponding to the x and y dimensions of a mounted cassette. The potentiometers are nonlinear so as to provide respective cosine and sine correction and thereby make the output signals substantially linear with the dimensions of sensed cassettes.

Abstract: An x-ray examination apparatus has an x-ray image intensifier and an x-ray film changer mounted so that the x-ray film changer can be moved to an exposure position, in front of the x-ray image intensifier, for producing x-ray pictures of an examination subject. The x-ray image intensifier has a holder on which the x-ray film changer is movably mounted so that, when in the exposure position, the film changer has the same image axis as that of the x-ray image intensifier. The film changer is pivotable out of the exposure position by approximately 90.degree. to a standby position. To avoid having the x-ray film changer in the standby position prevent access to a patient on an examination table, and to permit the x-ray image intensifier to be adjusted to any arbitrary position without being impeded by the film changer in the standby position, the examination apparatus has a holder for the film changer in the form of a bearing which at least partially surrounds the x-ray image intensifier.

Abstract: An improved gantry for an examination apparatus, such as an x-ray apparatus comprising a source of x-rays and a detector of fluoresced photons, is disclosed. The apparatus is particularly suitable for use in a vehicle such that the examination can be carried out at locations convenient to the patients. The apparatus comprises a vertical standard and first and second carriages. The first carriage is movable along the vertical standard and carries a horizontal arm. The horizontal arm carries the second carriage, which moves along the horizontal arm in a direction orthogonal to the axis of the standard. A transverse arm carrying the x-ray apparatus is carried by the second carriage and moves with respect thereto in a third direction orthogonal to the first and second directions, so that three directions of motion along orthogonal axes are thus provided. Additionally, the second carriage is rotatable about the horizontal arm providing a first direction of rotation.

Abstract: A method and system are disclosed for producing a photographic image of an X-ray pattern, including the following steps: converting the X-ray pattern to a first pattern of light; exposing a photographic film to said first pattern of light; detecting the light at elemental regions of the first pattern; generating a second pattern of light in a pattern which depends on the detected light; and exposing the photographic film to the second pattern of light. The disclosed invention provides improvement on the standard radiographic method in the following ways: (1) The recorded film contrast in low X-ray exposure regions that ordinarily would have been recorded in under-exposed regions of the film's characteristic curve will be increased significantly. (2) The overall range of light transmission that must be viewed by the radiologist will be decreased without sacrificing diagnostic information.

Abstract: A method and device for use in combination with a dental x-ray film for reducing the pain, discomfort or tissue trauma associated with the emplacement of such a film into the oral cavity of a patient, the device comprising a tubular member formed of a soft, resilient nontoxic material, the member having an axially extending slot which extends radially into the member, the slot adapted to receive an edge of a dental x-ray film therein.

Abstract: X-ray film feeding magazine usable in a film handling automatic apparatus, comprising a tray (3) in which is defined a housing (26) to receive an x-ray film packet (F). The film housing is delimited by a front gauge (17) and at least a side gauge (28) which can be shifted between a stand-by position and a work position to reduce the housing dimensions to prearranged values. The shifting of said movable front and side gauges from the stand-by to the work position is controlled by means of contrast elements (15) which are associated with the front gauge and accessible from the outside to apply an external thrust to the front and side gauges.

Abstract: A radiological scanning apparatus for forming an image of an object on a film by scanning said object with a flat fan shaped beam. The film is conformed so as to form a surface of revolution. The surface of revolution is, on the one hand, moved in the same movement as the scanning movement of said beam, and on the other hand it is rotated about its axis of revolution so as to renew a surface exposed to said beam in order to reduce the dimension of said film considered in the direction of said scanning movement.

Abstract: An apparatus for supporting an X-ray unit in a vertically adjustable manner. The apparatus includes a frame having two posts and a carrier supported between the posts. The post are slotted and the carrier includes guide members received within the slots. The carrier also includes a counterbalance for supporting the carrier between the post. The counterbalance includes a support cable and force element.

Abstract: In medical X-ray apparatus including a stand mounting an X-ray tube and two X-ray receptors such as an image intensifier and a film exchanger, the two X-ray receptors are mounted on a common frame pivoted to present either receptor at the image plane of the X-ray tube. Additionally the two receptors slide on the frame and are linked by a bell crank for coordinated rotation and sliding movement which restores their common center of gravity to its initial locus as one receptor is interchanged for the other. Balance of the receptors with the X-ray tube on the frame is thereby maintained.

Abstract: A gate assembly comprising a pair of leaves positioned behind the opening of a housing. After an x-ray cassette is placed through the gate assembly, the leaves rotate to prevent entering of any additional x-ray cassettes or foreign objects.

Abstract: A method and apparatus are disclosed for performing in-bath filming during extracorporeal shock wave lithotripsy. The device has a holder for slidably receiving a film cassette and a grid therein. The holder has means for slidably mounting the holder on the image intensifier portion of an x-ray fluoroscope so that forces on the front of the holder can be transferred to pressure sensing means on the intensifier. The holder is constructed in a water-tight manner so that the film contained in the holder may be delivered beneath the level of water in the bath adjacent the abdomen of the patient in the bath. An inflatable bladder is provided on the outside of the holder to displace water from the area between the holder and the abdomen to prevent absorption and scattering of the x-rays by water in the area between the holder and the patient's abdomen.

Abstract: A radiological installation for front and profile examinations using a single image receiver. The receiver is fixed to a transverse arm with respect to the table by means of a rotation shaft which may be locked in at least two predetermined positions, said arm forming part of a mobile support movable along said table.

Abstract: A movable apparatus for insuring the taking of X-Rays in any location and under safe aseptic conditions. A tube assembly forms a tripod for supporting an X-ray cassette. A caisson suitable for containing the tube assembly and the cassette includes, for example, a tank of decontamination material released inside the caisson after its lid is manipulated to place the cassette inside the caisson. The caisson may also include an ultraviolet lamp for providing further decontamination. This permits the taking of X-rays, directly over the patient's bed, while avoiding contamination by germ transfer.

Abstract: An X-ray film holder which permits optional fluoroscopic or radiographic examination of a patient has a number of screen foils disposed in a film conveying track wherein X-ray film is provided between a supply magazine and a take-up magazine. The film changer is disposed between the patient and an X-ray image intensifier, the changer and the intensifier having the same image axis. The film changer has a conveyor unit for moving the screen foils into place in front of the image intensifier and for automatically opening overlapping flaps of the screen to permit an X-ray film sheet to be moved therebetween. As needed, the screen foils can be conveyed in an opposite direction to a storage area to permit radiation to pass unobstructed to the image intensifier for fluoroscopic examination of the patient.

Abstract: A method of manufacture of an anti-scatter grod structure for protectively housing a grid therein, the steps of cutting a solid upper and lower plates to a given size lightly larger than the cassette to be housed by the grid structure, forming a generally U-shaped frame structure with interior vertically spaced ledges with an upper ledge being sized for supporting the lower plate and with a lower ledge being vertically spaced therefrom and sized for under lapping the lower plate and supporting a cassette in assembly with the frame, securing the lower plate in assembly with the frame while engaged with the upper ledge, mounting a grid in centered relation on the lower plate and limiting the extent of shifting movement of the grid relative to the lower plate, positioning a solid upper plate over the grid in parallel relation to the lower plate, and securing the solid upper plate to the U-shaped frame structure in unitary assembly.

Abstract: An X-ray diagnostics installation has an X-ray tube for directing an X-ray beam at an examination subject disposed within the beam path on a support plate, the support plate having a secondary radiation grid on one side thereof, and having a receptacle therein for an X-ray film cassette. The support plate is mounted so as to be rotatable about an axis which is perpendicular to a central ray of the X-ray beam such that the secondary radiation grid can be optionally disposed in front of or behind the X-ray film cassette as viewed in the radiation direction, while the film focus distance remains the same.

Abstract: A device for feeding and positioning a recording medium as in a radiographic apparatus includes a grip member for gripping, feeding, and positioning the recording medium therein, the grip member being composed of a first plate, a second plate disposed in confronting relation to the first plate and openable at least in an upper end portion thereof with respect to the first plate, and a cover member disposed for closing and opening a gap between lower ends of the first and second plates.

Abstract: A container for radiographic film cassettes particularly adapted for adhering to surfaces. In combination, a container comprises a substantially flatened container space therein for receiving and x-ray cassette, with one end of the container permanently closed, and the second end adaptable between opened and closed positions. The container would further comprise a plurality of suction cup members substantially located at each corner of the container for suctionally adhering to the surface to be x-rayed. There is further provided a pair of handle members extending along the top side of the container for manually gripping the handle members for removing the container from the surfaced x-rayed by overcoming the suction between the container and the surface.

Abstract: A life support stretcher bed includes an undercarriage which is supported on the ground for movement from one location to another by respective wheels which are commonly lockable by a braking mechanism to prevent movement of the undercarriage from a selected location. A platform is supported on the undercarriage for raising and lowering relative thereto by means of a hydraulically operating lifting arrangement which includes a control arrangement mounted on the undercarriage. An intraaortic balloon pump unit that is supported on the ground by respective casters for movement in any direction along the ground is connected to the undercarriage for shared movement therewith at a predetermined distance from the undercarriage. The platform includes straps for holding the patient supported in a supine position on the platform in such position, and side rails which can be moved from a position above the platform into an out-of-the way position.

Abstract: A radiographic apparatus for facilitating insertion of a radiographic element on a carrier into the retractable opaque envelope of a film unit for exposure purposes, and for facilitating its later removal, includes a housing having a light tight chamber for receiving the carrier and film unit arranged in superposed relation therein. When the housing is in an upright loading position and the envelope is retracted, gravitational force urges the carrier into contact with the negative sheet so that both are enclosed when the envelope is moved back to its closed position. During removal operations, the housing is inverted, allowing gravitational force to urge the carrier away from the negative sheet so that the envelope passes therebetween when returned to its closed position, leaving the carrier outside of the envelope.

Abstract: An X-ray film cassette holder for use in X-raying injuries to large animals in the field, especially race horses, and especially adapted to knee and ankle X-ray procedures.

Abstract: Apparatus for loading a radiographic film packet with an intensifying screen, and for discharging the exposed negative into automatic processing apparatus without the use of a darkroom.

Abstract: Suspension apparatus is disclosed for holding an X-ray film cassette frame. The apparatus includes clamping means attachable to a suitable support and or a series of independently adjustable arms providing a support for the cassette frame. The arms are adapted for adjustment variously in horizontal and vertical planes with reference to the mounting position of the clamping means and cooperate to extend and retract relative to said clamping means. Thus the cassette frame can be moved through included angles of 360.degree. in both the horizontal and vertical planes and can be extended and retracted between the clamping means and a subject to be photographed. In practice with the present invention it is possible to X-ray a wide variety of different areas of a patient while permitting the subject to remain immobile by adjusting the X-ray film in the cassette to accommodate the position of the immobile patient.

Abstract: The disclosure relates to an apparatus for the safe-keeping of a sheet of film before, during and after its exposure in, for example, an X-ray camera, the apparatus being in the form of a box of great length and width and low height, the box having an openable and closable lid.The inventive concept forming the basis of the present invention is that of realizing an improvement to aid in, and more effective equipment for, the safekeeping of film sheets.Such a concept is achieved according to the present invention in that the apparatus disclosed by way of introduction is characterized in that the bottom and at least one side wall, which preferaby is a longitudinal side wall, are disposed in an integral unit, the longitudinal side wall consisting of a strip bent at a right angle to the bottom.

Abstract: An apparatus for holding x-ray cassettes and grids in which any grid of a specific length and width can be combined with any cassette of a corresponding length and width without regard to the cassette thickness. The apparatus includes a frame assembly having side rails with flanges and a back rail with flanges which form two channels, one for the grid and one for the cassette. The cassette channel is dimensioned to accept any thickness of cassette. Parabolic springs are located within side rail cassette channel portions to bias the cassette against selected flanges. Locater members are also provided to properly align the grid and the cassette.

Abstract: A magnetic friction device for permitting one machine member to be moved relative to another by applying a predetermined force and for holding one member in a fixed position when the force is discontinued. One member is magnetically susceptible and has a smooth surface interfacing with but slightly spaced from a surface on the other member. Said other member's surface has one or more recesses in which there are magnetic disks of a polymer impregnated with magnetic particles. The disks are attracted to the smooth surface to produce a design controlled predetermined frictional force.

Abstract: An X-ray film cassette holder has adjustable end retaining means pivotally mounted on an end of a pivotally adjustable link that is adapted for clamping by a bottom plate and adjustable clamping plate to an edge of an X-ray table for positioning X-ray film for different angles of cross table radiography.

Abstract: A serial radiograph system has an improved film changer featuring reusable film pack containers. An exposure station through which X-rays are directed is virtually free of X-ray absorbing material providing a "see through" station. As a consequence of the "see through" exposure station, an image intensification tube positioned under the exposure station provides an unobstructed fluoroscopic image with minimum X-ray dosage to a patient.The film changer utilizes film packs, each of which has a semienclosed, partially sealed, pouch. Each pouch contains a sheet of radiographic film between a pair of intensifying screens. A plurality of the film packs are stacked in a novel supply magazine and are sequentially transported to the exposure station by a transport system having a plurality of pinch roll pairs.

Abstract: X-ray apparatus for angiography has a support member which is rotatable about a vertical axis and a U-shaped arm mounted on the support for rotating about a horizontal axis. A radially movable carriage with an x-ray source mounted on it is mounted at one end of the U-arm. Carriages which are movable linearly and radially relative to the horizontal axis support an image intensifier and a film changer respectively. The horizontal axis and vertical axis of rotation which is coincident with the x-ray beam axis intersect at a point which is isocentric. Images can be obtained with either the intensifier receptor or film changer receptor in varying degrees of magnification and without magnification while the patient being examined remains coincident with the isocenter. Means are provided for counterbalancing the source, changer and the intensifier independently.