Cancellation coil arrangement for reducing stray magnetic field emissions from CRT displays

PCT No. PCT/GB95/01928 Sec. 371 Date Jun. 5, 1997 Sec. 102(e) Date Jun. 5, 1997 PCT Filed Aug. 15, 1995 PCT Pub. No. WO96/23315 PCT Pub. Date Aug. 1, 1996A cathode ray tube display comprises a cathode ray tube (10) having a screen (11) connected to a neck portion (12) via a bell portion (13). Cancellation coil means (160,160') are arranged to receive a signal based on a scanning signal for the cathode ray tube and arranged to reduce stray magnetic fields radiating from the display. The cancellation coil means comprises a first cancellation coil (160) and a second cancellation coil (160') located on each of opposite sides of the cathode ray tube. The first cancellation coil (160) are located adjacent the bell portion and the second cancellation coil (160') being located adjacent the neck portion. The first and second cancellation coils each being contained in a plane substantially perpendicular to the screen of the cathode ray tube.