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LCD displays
Much of the discussion of refresh rate does not apply to LCD monitors. This is because while a phosphor on a CRT will begin to dim as soon as the electron beam passes it, LCD cells open to pass a continuous stream of light, and do not dim until instructed to produce a darker color. Pertaining to LCDs, see also response time.
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At the moment, a CRT screen is more suitable than an LCD screen for the playing of motion graphics such as are in games and video. This is because LCD technology is not yet as rapid as CRT technology at refreshing the screen, the technical term for which is the refresh rate for a CRT monitor - the frequency at which the screen is redrawn, in Hertz (Hz), or cycles per second. At refresh rates below 70Hz, most people can see the screen flicker, which causes them eye-strain.
Strictly speaking, the refresh rate for an LCD monitor is called its pixel response time, because LCD technology doesn't refresh the screen in the same way as with a CRT monitor, but for the sake of convenience, I'll just call the process the refresh rate for both types of monitor. This is usually between 20 and 50 milliseconds. It is measured in milliseconds not Hz, as with CRT monitors. The lower the pixel response time, the faster the pixels refresh (turn off and on), making the screen update faster - an important factor for gamers.
When an LCD screen displays images that show rapid movement, a blurring effect called ghosting will be evident. How much ghosting there is depends on the quality of the monitor. However, the technology has improved to the point now that ghosting has almost been eliminated on LCD displays of quality.
The screen resolution is determined by the number of pixels in use by the viewable area of the screen. The pixels are the small dots that give colour to the screen. If the screen resolution is 800X600 pixels (480,000) for a 15" CRT monitor, the screen has a width of 800 pixels and a height of 600 pixels. But if the same screen size has the screen resolution set to 1024X768, nearly double the number of pixels (786,432) are employed to create the image.