Differences of Raster Scan and Random Scan Display
The main difference between raster scan and random scan lies in the drawing of a picture where the raster scan points the electron beam at the entire screen but incorporating just one line at a time in the downward direction.Random scan monitors draw a picture one line at a time and for this reason are also referred to as vector displays (or stroke-writing or calligraphic displays).The component lines of a picture can be drawn and refreshed by a random-scan system in any specified order .Raster-Scan Displays. In a raster- scan system, the electron beam is swept across the screen, one row at a time from top to bottom. As the electron beam moves across each row, the beam intensity is turned on and off to create a pattern of illuminated spots.A vector monitor or vector display is a display device used for computer graphics up through the 1970s. It is a type of CRT, similar to that of an early oscilloscope. ... Some refresh vector displays use a normal phosphor that fades rapidly and needs constant refreshing 30-40 times per second to show a stable image.A raster is technically characterized by the width and height of the image in pixels and by the number of bits per pixel (or color depth, which determines the number of colors it can represent).