Persistence, resolution and aspect ratio in video displays

Persistence: Persistence is the time to which the phosphors in the cathode Ray Tubes emit light until the next electrons is fired. It is actually a measure of time taken by the emitted light from screen to decay one tenth of its original intensity. Lower persistence phosphors require higher refreshing rate to avoid flickering. Lower persistence phosphors are usually used for animations. Higher persistence phosphors are used to display complex images.

Resolution: Resolution is actually the number of dots per centimeter that can be displayed horizontally and vertically in a Cathode Ray Tube. It depends on type of phosphors, focus and deflection method in Cathode Ray Tube, and the intensity.

Aspect Ratio: It is the ratio of number of vertical points to horizontal points which plotted will generate equal sized lines. Example: 3/4 aspect ratio means that a vertical line with 3 points is equal in length to the horizontal line with 4 points.


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