MISLANDING ADJUSTER FOR ELECTRONIC BEAM OF COLOR CATHODE-RAY TUBE

摘要

PROBLEM TO BE SOLVED: To automatically adjust the mislanding quantity of electronic beam with high accuracy in a short time by measuring the mislanding amounts of respective primary color electronic beams at plural measuring points on the surface of color cathode-ray tube(CRT) and correcting the mislanding amounts of respective primary color electronic beams at positions closer to the display screen of color CRT. ;SOLUTION: Based on mislanding measuring data at nine positions due to photosensors 4a-4i measured by a landing measuring means 5, a CPU 7 lets a positive or negative current flow to correction coils 3a-3d by controlling a correct current generating means 2 so that the absolute value of that mislanding quantity can be a minimum value less than a prescribed value. Thus, the quantity of mislanding from the landing positions of respective primary color electronic beams on the display screen to regular landing positions is controlled less than the prescribed value by the synthetic magnetic field of four magnetic fields generated by this current.;COPYRIGHT: (C)1998,JPO