| 摘要 |
PURPOSE:To correct pattern distortion with simple circuit constitution and high accuracy by controlling a deflection output based on a beam detection output of a linear beam detection sensor provided adjacently at the outside of an effective fluorescent screen of a cathode-ray tube. CONSTITUTION:Two linear optical sensors 6a, 6b are provided at the outside of the effective fluorescent screen 2a of the cathode-ray tube 2. The optical sensor 6b at the outside of the two optical sensors detects whether or not overscanning state exists and the inner optical sensor 6a detects whether or not scan deficiency exists. The output of the optical sensors is fed to a horizontal amplitude control current generator 53 via amplifiers 52, 51 and the current fed to a control winding of a saturated reactor 54 is controlled depending on the excess or deficiency of the detected horizontal amplitude. As a result, the amplitude of the horizontal deflection current flowing to a horizontal deflection coil 435 is controlled to attain prescribed scanning state. |
