Picture Tube of TV Receiver


Picture Tube of TV Receiver


The picture tube of a television receiver is a cathode ray tube (CRT) employing magnetic deflection. The picture sent out by the transmitting station is reproduced in the Picture tube. In the picture tube, the electron beam is deflected by a magnetic field. The magnetic deflection is obtained with the help of horizontal and vertical deflection coils in the yoke around the tube neck. The deflection provide the scanning of the beam on the fluorescent screen of the tube. The picture signal is fed to the grid of the electron gun. The instantaneous value of the pictures signal thus controls the instantaneous beam current and hence the brightness of the spot on the screen. In this way, the picture elements scanned at the television camera tube in the transmitter are reproduced on the fluorescent screen of the picture tube. When the screen is viewed from a distance, the tiny picture elements blend in a smooth way to produce the impression of a continuous picture.


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