Abstract: A gamma camera system includes two or more radiation detector heads and which are mounted opposite each other to a gantry for rotation about a subject. A transmission radiation source assembly is mounted to the front face of at least one of the detectors and can be moved across the face of the detector. The source assembly includes a radiation attenuating housing, a leaded bronze source holder, and a radionuclide source. The radionuclide source is retained in a longitudinal groove disposed in the source holder. The source holder may be rotated into open, closed, and access positions. The transmission radiation emitted by the source assembly is directed across the examination region, attenuated by the subject, and detected by the opposed detector. The gamma camera system also includes a filter which selectively attenuates the transmission radiation to obtain a desired attenuation profile which prevents saturation of the opposed detector.

Abstract: A gamma camera system includes two or more radiation detector heads and which are mounted opposite each other to a gantry for rotation about a subject. A transmission radiation source assembly is mounted to the front face of at least one of the detectors and can be moved across the face of the detector. The source assembly includes a radiation attenuating housing, a leaded bronze source holder, and a radionuclide source. The radionuclide source is retained in a longitudinal groove disposed in the source holder. The source holder may be rotated into open, closed, and access positions. The transmission radiation emitted by the source assembly is directed across the examination region, attenuated by the subject, and detected by the opposed detector. The gamma camera system also includes a filter which selectively attenuates the transmission radiation based on the attenuation profile of the object so as to prevent saturation of the opposed detector.

Abstract: A rotatable gantry portion (16) is rotatably mounted on the stationary gantry portion (18) of a SPECT camera. A plurality of radiation detector heads (10a, 10b, 10c) are mounted to the rotating gantry. A transmission radiation source holder and collimator assembly (40, 42) is mounted to the rotatable gantry portion opposite one of the detector heads. A transmission radiation source (60) is mounted in a lead shield (62) with an opening (64) pointing toward an examination region (12). A shutter (66) is rotatable between a closed position in which a lead arc segment (70) blocks the opening (64), a calibration orientation in which tin (72) covers opening (64), and an open position in which an opening (74) is aligned with the opening (64). A safety interlock means (80) locks the shutter in the closed position and against rotation when the radiation source holder is removed from the rotatable gantry portion. A collimator (42) has lead side walls (200) and tin or tin alloy septa (202).

Abstract: There is disclosed an improvement in a system for sensing information encoded on a duplicating original, using the information to control copy processing. A duplicating original is installed onto the surface of a cylinder revolving in the duplication process. The encoded information, in the form of indicia printed on the original, is sensed by an optical read head arranged to scan the revolving cylinder. Signals indicating the position of the revolving cylinder are used to determine when to scan for information. Finally, the information sensed, e.g., the copy quantity, is used to control the processes of the duplicating machine. The manner in which the encoded information is arranged conforms to the writing capabilities of a computer output printer, which is preferably also used to prepare the body of text material being duplicated, and the read head is arranged to sense the thus applied indicia and reproduce the information accurately, allowing wide latitude for correct placement of the information.