The refresh rate is the number of times per second that display hardware re-draws the data on the screen, which is different from the number of unique frames, or images, that are displayed. For instance, movies are filmed at a rate of 24 frames per second, but an LCD TV display will refresh the screen more often–the refresh rate is usually from 60 to 240 times per second. Because 60 is not divisible by 24, movies played on a 60 hertz refresh rate set are not perfectly smooth, but a 120 hertz or 240 hertz TV will display them properly, because they are evenly divisible by 24. The NTSC standards for TV are set at 30 frames per second, so movies displayed over TV stations require the same adjustment techniques that won’t be perfectly smooth.
- By Lowell Heddings on 08/19/12