# Why would a screen(with touch controls) in a vibrating environment be readable if its refresh rate is dynamically matched with vibrations?

So, I was reading about this Dragon V2 and it has got touch controlled screens, but screen might be unreadable for pilots because of engine vibrations and whatnot. I came across this comment on reddit.

"I read an article on the SLS/Orion. They had a problem with vibrations making screens unreadable. It would have cost millions of dollars to dampen the pod vibrations so the pilots could read their instruments. Then a scientist realized that if you changed the monitor refresh rate to match the vibrations, the screens looked perfectly clear. The million dollar fix was abandoned for a 10 cent accelerometer that adjusted the refresh rate automatically. I see no reason why spacex couldn't use this solution to make the screens useful in the rigor of flight. "

Yeah, so, why does matching refresh rate with vibrations solves this?

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let's suppose you're trying to look at a light which is vibrating between the two points $A$ and $B$:
The rapid vibration blurs the light out into a line so you can't see it clearly. However suppose we turn the light on and off in time with the vibrations so it's on when it's near point $B$ and off everywhere else:
You can only see the light when it's on, so now you see the light (reasonably) clearly at point $B$ even though it's still vibrating around.