Logic controlled degaussing system
Cathode ray tube display with combined degauss and surge limiting circuit
Magnetic field compensation apparatus
Circuit for the compensation of the horizontal component of the earth's magnetic field for a color picture tube of a high-resolution monitor
Demagnetizer for display unit Patent #: 5475283
ApplicationNo. 567988 filed on 12/11/1995
US Classes:348/820, External electric or magnetic effect315/8, Compensating for stray deflecting fields315/85, WITH ELECTROMAGNETIC WAVE RADIATION PREVENTING OR SHIELDING MEANS361/150Television degaussing
ExaminersPrimary: Burgess, Glenton B.
Attorney, Agent or Firm
Foreign Patent References
International ClassesH04N 009/29
Foreign Application Priority Data1994-12-15 JP
AbstractA CPU is designed so as to put a demagnetizing circuit in an operative state in accordance with a result of detecting, among other quantities or events, the number of operations to turn on a power counted by a counter, the lapse of time under a predetermined condition measured by a timer since the pulling-out of an AC plug, the movement of the main body of a display device sensed by a sensor unit, an external magnetic field sensed by a sensor unit or a residual magnetism in a CRT itself sensed by a sensor unit. Instead of carrying out demagnetization each time the power is turned on, demagnetization is performed only under certain conditions when necessary, diminishing the problem of wasteful power consumption. On the top of that, the number of cases in which sound and picture vibration are generated due to a demagnetizing operation carried out right after the turning-on of the power is reduced, resulting in a product easy to handle by the user. In addition, the lives of components composing a demagnetizing circuit such as a positive thermistor can be prolonged.