Abstract: A radiotherapy system comprising a support for a patient undergoing radiotherapy treatment, a gantry rotatable about an axis, a source of radiation mounted on the gantry and producing a beam of radiation directed towards a target region of the patient, a collimator coupled to said radiation source, the collimator comprising a plurality of movable, beam-limiting elements, to collectively define a shaped aperture through which the radiation beam passes, a portal imager mounted on the gantry opposite the radiation source for detecting the radiation after it has passed through the patient and generating corresponding images, and associated circuitry for controlling at least the gantry, the source, the collimator, and the portal imager, collating detected data comprising a plurality of images acquired including images at a plurality of angles of rotation of said gantry and images at a plurality of collimator shapes; generating a three-dimensional image of the target region based thereon.

Abstract: A radiotherapy system comprising a support for a patient undergoing radiotherapy treatment, a gantry rotatable about an axis, a source of radiation mounted on the gantry and producing a beam of radiation directed towards a target region of the patient, a collimator coupled to said radiation source, the collimator comprising a plurality of movable, beam-limiting elements, to collectively define a shaped aperture through which the radiation beam passes, a portal imager mounted on the gantry opposite the radiation source for detecting the radiation after it has passed through the patient and generating corresponding images, and associated circuitry for controlling at least the gantry, the source, the collimator, and the portal imager, collating detected data comprising a plurality of images acquired including images at a plurality of angles of rotation of said gantry and images at a plurality of collimator shapes; generating a three-dimensional image of the target region based thereon.

Abstract: A radiotherapy system is disclosed, comprising a support for supporting a patient undergoing radiotherapy treatment, a gantry that is rotatable about an axis, a source of radiation mounted on the gantry and producing a beam of radiation directed towards a target region of the patient, a collimator coupled to said radiation source for collimating said radiation beam, the collimator comprising a plurality of beam-limiting elements, each movable to collectively define a shaped aperture through which the radiation beam passes, a portal imager mounted on the gantry opposite the radiation source for detecting the radiation after it has passed through the patient and generating corresponding images, and associated circuitry for controlling at least the gantry, the source, the collimator, and the portal imager, collating detected data comprising a plurality of images acquired from the imager including images at a plurality of angles of rotation of said gantry and images at a plurality of collimator shapes, and genera

Abstract: A radiotherapy system is disclosed, comprising a support for supporting a patient undergoing radiotherapy treatment, a gantry that is rotatable about an axis, a source of radiation mounted on the gantry and producing a beam of radiation directed towards a target region of the patient, a collimator coupled to said radiation source for collimating said radiation beam, the collimator comprising a plurality of beam-limiting elements, each movable to collectively define a shaped aperture through which the radiation beam passes, a portal imager mounted on the gantry opposite the radiation source for detecting the radiation after it has passed through the patient and generating corresponding images, and associated circuitry for controlling at least the gantry, the source, the collimator, and the portal imager, collating detected data comprising a plurality of images acquired from the imager including images at a plurality of angles of rotation of said gantry and images at a plurality of collimator shapes, and genera

Abstract: A photovoltaic system includes a first submodule and a second submodule connected in parallel.

Abstract: Luminance signals, subject to high frequency pre-emphasis, are applied to a first double-ended signal clipping circuit prior to combination with chrominance signals (in the form of modulated color subcarrier waves) to form a composite color video signal. The composite signal is fed to a second double-ended signal clipping circuit having clipping levels beyond those of the luminance signal clipper. The output of the second clipping circuit serves as the modulating signal input for a picture carrier frequency modulator.

Abstract: In playback of a video record (e.g., in video disc form) employing a FM carrier recording format, a defect compensation system is provided which substitutes delayed video signals for current video signals when a defect is encountered. The current video signals are obtained from the output of the player's pickup-responsive FM detector (illustratively of the zero-crossing detector type) via appropriate frequency responsive circuitry comprising a low pass filter (encompassing the recorded video signal bandwidth: e.g., 0-3 MHz.). To detect the occurrence of a defect, the FM detector output is also supplied to additional frequency responsive circuitry having a wideband response which desirably extends from DC to an upper frequency limit (e.g., 0-6 MHz.) well above the highest frequency of the video signal subject to recording.