Apparatus and method for compensating the distortion on a screen display
AssigneeMitac International Corp.
InventorCheng-Di Tsai
Life of this patent
Estimating the term…
Abstract
The present invention includes a DC signal generating circuit for generating a DC signal and a ramp signal generating circuit for generating a periodic ramp signal. A synthesizing circuit is then used to combine the DC signal and the ramp signal to generate a synthesized signal, where the DC level of the synthesized signal is determined by the DC level of the DC signal. A driving circuit is used to amplify the power of the synthesized signal. A rotate coil surrounding the neck of a cathode-ray tube is responsive to the amplified synthesized signal, and therefore generates a magnetic force to turn electron beam in the cathode-ray tube, thereby compensating the trapezoidal distortion on the bottom and the top edges of a screen display.
Claims22
Apparatus for compensating trapezoidal distortion on a bottom edge and a top edge of a screen display, comprising:
- DC signal generating means for generating a DC signal;
- ramp signal generating means for generating a periodic ramp signal;
- synthesizing means for adding said DC signal and said ramp signal to generate a synthesized signal, the DC level of said synthesized signal being determined by the DC level of said DC signal;
- driving means for amplifying the power of said synthesized signal;
- and
- rotate coil means surrounding the neck of a cathode-ray tube, responsive to said amplified synthesized signal, for generating a magnetic force to turn an electron beam in the cathode-ray tube, thereby compensating the trapezoidal distortion on the bottom edge and the top edge.
Apparatus for compensating trapezoidal distortion on a bottom edge and a top edge of a screen display, comprising:
- DC signal generating means for generating a DC signal;
- ramp signal generating means for generating a periodic ramp signal;
- an adder for adding said DC signal and said ramp signal to generate a synthesized signal, the DC level of said synthesized signal being determined by the DC level of said DC signal;
- an amplifier for amplifying the power of said synthesized signal;
- and
- a rotate coil surrounding the neck of a cathode-ray tube, responsive to said amplified synthesized signal, for generating a magnetic force to turn an electron beam in the cathode-ray tube, thereby compensating the trapezoidal distortion on the bottom edge and the top edge.
A method for compensating trapezoidal distortion on a bottom edge and a top edge of a screen display, comprising the steps of:
- generating a DC signal;
- generating a periodic ramp signal;
- adding said DC signal and said ramp signal to generate a synthesized signal, the DC level of said synthesized signal being determined by the DC level of said DC signal;
- amplifying the power of said synthesized signal;
- and
- generating a magnetic force to turn an electron beam in the cathode-ray tube, thereby compensating the trapezoidal distortion on the bottom edge and the top edge.
Dependencies are inferred from the claim text.