| 摘要 |
For improving the sharpness of image produced on the screen of a cathode ray tube in a television receiver or other video signal is produced to vary is response to transient changes in the level of a video signal by switching each electron beam in the cathode ray tube is density-modulated, and the control signal is supplid to a beam focusing electrode of the cathode ray tube so as to control the shape of beam landing spot on the screen and thereby to prevent the image on the screen from becoming vague at its contours. |
