Coil device for image pickup tube

摘要

The invention provides a coil device having horizontal and vertical deflection coils around an outer surface of an image pickup tube to generate magnetic fields for deflecting electron beams in the horizontal and vertical directions, respectively. A correction coil is disposed between the outer surface of the image pickup tube and the horizontal deflection coil so as to correspond to the position of the vertical deflection coil. The number of turns of the correction coil is smaller than that of the vertical deflection coil. A signal for correcting scanning distortion of the electron beam caused by the deflection magnetic fields is supplied to the correction coil. The time constant of the correction coil is smaller than the period of the horizontal deflection signal. The correction coil is made of a printed circuit wiring.