Response time is basically the time it takes a pixel to change from either black to white or from one shade of gray to another. The lower the response time, the better the performance of the monitor.
You get 2 options, either a low response time of 1 millisecond on TN panels or 4 milliseconds on IPS or VA panels.
You have to keep in mind though that the monitor’s response time isn’t the same as input lag. The latter is supposed to signify the delay between the click of a key and the resulted action of that click on your screen.
Response time, however, is the performance of each individual pixel independently and not the overall display of the content.
The ability to change from white and black and from one shade of gray to the other indicates the intensity of the appearance of colors on your monitor when using a filter. It also –in a sense- controls how pix-elated the fast-moving objects would look on your screen.
Response times work with refresh rates, so, for example, a monitor with a 60 Hz refresh rate will keep an image on the screen for a little less than 17 seconds. This means the pixels would need to transition faster than that so they can display the next frame or image in time.
Another problem that could be caused by longer response times is that they may result in an effect called “ghosting”.
This is when you can still see the details of the previous frame while the next one is being displayed because the pixels took too long to switch between the different shades of gray.
This may not be a big deal if you’re doing every day computing like browsing the internet, reading an article, or writing an essay.
However, if you’re a hardcore gamer or like to watch fast-paced action movies and series, you will definitely make use of the lower response times typically found on TN (Twisted-nematic) panels.
Although you may have to be willing to give up on some of the visuals so you’ll get narrower viewing angles, a narrower color gamut coverage, and color reproduction that falls short of that of the IPS panels’.