The portion of the video signal when brightness is suppressed at the end of a field, during which the electron beam retraces from the bottom to the top of the screen.
Turning off the electron beam in a CRT during the time the beam returns from the bottom of the screen to the top after scanning each field of a picture. If vertical blanking does not occur, a diagonal retrace line will display from the lower right to the upper left of the screen. Also see " Retrace."
Also called retrace, this is the process of bringing the scanning electron beam in a CRT from the bottom of the picture back up to the top of the picture. During this time the electron beam is shut off (blanked). Approximately 92% of the frame period is spent writing active horizontal lines, while the remaining 8% is spent on vertical retrace.