摘要:
A portable XRF analyzer includes a hand shield to substantially block x-rays from impinging on a hand of a user. The portable XRF analyzer includes a heat sink over an x-ray source and a heat sink over an x-ray detector. The heat sinks are separated from each other by a thermally insulative material.
摘要:
An apparatus for attenuating high energy radiation including an attenuation member for attenuating high energy radiation in a high energy radiation field emitted from a high energy radiation source towards a subject. A control unit is provided for selectively activating the attenuation member. A method for attenuating high energy radiation is also disclosed.
摘要:
A multiple layer multileaf collimator for shaping a radiation beam. The collimator comprises first and second layers of a plurality of elongated radiation blocking leaves. The leaves of each layer are arranged adjacent one another so as to form two opposed rows of adjacently positioned leaves and are movable in a longitudinal direction (Y) which is generally traverse to the direction of the beam so as to define a radiation beam shaping field between the opposed ends of the leaves. The layers are arranged one above another in the beam direction and offset in a lateral direction (X) generally transverse to the beam direction and orthogonal to the longitudinal direction (Y) so that spaces between adjacent leaves of the first and second layers are positioned over and under, respectively, leaves of the second and first layers, respectively.
摘要:
A device for calibrating a criticality detector for a nuclear fuel manufacturing plant having a radiation source comprises a radiation protective holder for containing the radiation source. The holder is aligned with the criticality detector along an axis; and a measuring rod having a plurality of calibrations is connected to the criticality detector and positioned near the holder parallel with the axis. A nylon guide is connected to the holder and movably connected to the measuring rod for moving the holder and the radiation source along the axis for detection purposes while providing a calibration measurement.
摘要:
A scanning device for examining an object with gamma rays with shielding for protection from radiation and protection of the mechanism from heat by a cooling jacket formed by spaced plates around the object. The shielding is formed by a pair of shutter-halves forming a lead shutter with mechanism to move the shutter-halves toward and away from each other and one of the shutter-halves mounted on a rotating drum which also carries three gamma ray sources. Gamma ray detectors are mounted in a circle concentric and outside the circle of the sources.
摘要:
A collimator is disclosed which has a stack of radiation opaque plates that is tilted to vary the angle of view of the scintillation crystal of a radiation detector with respect to a radiation source. The plates have hexagonal apertures that are aligned with corresponding apertures on adjacent plates to provide radiation transmitting channels. As the stack is tilted, the plates slide laterally over one another to change the slant of the channels.
摘要:
In a rotating fan beam tomographic scanner there is included an adjustable collimator and shutter assembly. The assembly includes a fan angle collimation cylinder having a plurality of different length slots through which the beam may pass for adjusting the fan angle of the beam. It also includes a beam thickness cylinder having a plurality of slots of different widths for adjusting the thickness of the beam. Further, some of the slots have filter materials mounted therein so that the operator may select from a plurality of filters. Also disclosed is a servo motor system which allows the operator to select the desired fan angle, beam thickness and filter from a remote location. An additional feature is a failsafe shutter assembly which includes a spring biased shutter cylinder mounted in the collimation cylinders. The servo motor control circuit checks several system conditions before the shutter is rendered openable. Further, the circuit cuts off the radiation if the shutter fails to open or close properly. A still further feature is a reference radiation intensity monitor which includes a tuning-fork shaped light conducting element having a scintillation crystal mounted on each tine. The monitor is placed adjacent the collimator between it and the source with the pair of crystals to either side of the fan beam.
摘要:
A mask substrate for use in an x-ray lithographic system comprises a boron nitride member (32, FIG. 2) coated with a polyimide layer (20) whose thickness is approximately the same as that of the boron nitride member. The substrate is mechanically strong and both optically and x-ray transparent. Mask patterns formed on the substrate are characterized by low distortion and a low defect density.
摘要:
In a spot film device, the inner and main carriages for a film cassette are positioned with reversible servo motors. An x-ray grid is mounted on the bottom of the main carriage and a cross grid is mounted on tracks beneath the carriage such that the cross grid may be used or not used for fluoroscopy and both grids may be used for radiography. Field defining masks are also mounted for translating selectively with the carriage. Individual reversible servo motor drives are used to advance and retract the masks and cross grid. Means are provided for absorbing shock or negating drive system momentum when the masks or grid are stopped abruptly. Reduced power is applied to the mask and grid drive motors when the masks and grid reach their stops for holding them against their stops. A motor driven palpator cone, having unique driving and locking means is provided. Means are provided for loading and unloading cassettes from either the front or rear of the spot film device.
摘要:
A tubus for defining the boundary of a beam of penetrating rays, which is preferably adapted for use in the radiation therapy. In a tubus of the above-mentioned type, the tube wall is thereby constructed of a plurality of over-lapping wall elements directed in parallel with the edge radiation of the radiation cone encompassed by the tubus, and suspended on the tubus housing so as to be displaceable to the direction of the edge radiation. That type of construction of the tubus facilitates the cross-section and also the surface of the focused radiation cone to be varied. Thereby it becomes possible to correlate the radiation field in a stepless manner by means of one and the same tubus over a wide range to almost every form and size of the illness spread.