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As far as I know, most monitors have a refresh rate of 60Hz. According to my understanding, the monitor takes 16.67ms (1/60) to refresh (update its display).

Does this also means that any monitor with 16ms response time and below is equally good because it still manages to "process" the image within 16.67ms?

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  • "Response time" is a somewhat meaningless term for digital monitors, unless you specify a context. Some monitors may have a significant latency (on the order of a second) between the time of arrival of the digital signal and the consequent updating of the visible display, due to buffering/decoding/rerasterizing that goes on inside. This isn't important for TV viewing, eg, but could be critical for a fast-action video game. Dec 29, 2012 at 17:07

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As far as I know, most monitors have a refresh rate of 60Hz.

Not quite.

Old fashioned CRT monitors drew the picture on the screen by hitting phosphor with an electron ray. The beam moved on and the phosphor would continue to glow for a short while. You needed to refresh this again with in a short period. 50 times per second was enough to produce a usable image. (In televisions they used longer glowing phosphors and refresh it 25 times per second, interlaced).

However:

  1. A faster refresh yielded a slightly less tiring image.
  2. Having the refresh rate of the CRT at the same frequency of the fluorescent tubes used in many offices resulted in interference.

For these reasons the refresh was often increased to 60, 72, or 75 times per second.
(Often limited by the capabilities of both the monitor and the graphical card).

This means the refresh rate of 60Hz is not quite universal, and only found in older CRTs or in offices where cheap CRTs or cheap graphical cards got used.


'LCD' screens however work differently. *1

With a flat panel the image is not refreshed as such. The display keeps the last image until changed. This yields a crispy, stable image.

Changing this image however takes some time. The first generation flat panels which got sold as monitors had a delay of about 50ms to change a pixel from black to white or vice versa. This is fine for office work, surfing etc etc.

Given its more stable image I think it is even better for most tasks, despite being slower.

Its only disadvantage would be with rapidly changing images (E.g. gaming). For those you either want a CRT or a monitor with a rapid screen refresh. 25ms or faster used to be accepted as enough for gaming.


*1 I know, not LCD but TN, IPS etc etc. However LCD seems to be the commonly used term. That or 'flat panel'.

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    Current LCD displays mostly have response times (time to switch a pixel's color) of 5 ms or 2 ms with the 2 ms being the more desirable. While fast action in gaming is often cited as creating the need for faster response, simple scrolling of a text page reveals the difference between slow and fast response displays - slow response "smears" when scrolling. Dec 29, 2012 at 17:00
  • Aye, it is faster these days. But the often mentioned values are gtg (gray to gray), which is much faster than the 'real' pixel refresh time. (Where with 'real' I mean changes such as black to white. Worst case changes).
    – Hennes
    Dec 29, 2012 at 18:38
  • My question is only in the scope of digital monitors, not CRT by the way. Anyhow my question was not answered.
    – elwc
    Dec 30, 2012 at 15:49

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