[balou23]

At some point there were LCD monitors that had very noticeable to me chequerboard pattern - like with analogue TV, only half of the screen got lit up/refreshed, but with an alternating pattern rather than scan lines.

After asking the owner of said screen how he could stand that... "stand what?"

Yep, I guess most people are not that picky.

[beagle3]

It’s not necessarily picky - it’s sometimes about physically different perception.

When DLP projectors first came out, I couldn’t watch them. I would see colors breaking in fast motion scenes and whenever I would move my head even slightly (and … we all move our head slightly often when watching a movie).

When I told other people, some of them nodded in understanding, but the vast majority thought I was making things up - for them, it was a rock solid picture.

One of my friends replied: “I can see about 300hz. Not all the time - only when I have secadic movements; but that means many fluorescents, DLPs and other light sources drive me crazy. I guess you’re also a member of crazy club”

Some people can hear 26khz. Some people can see DLPs. Some people can see the alternating pattern….

[ssl-3]

I had a (regrettable) 19" 4x3 ViewSonic display that made that problem obvious -- way back in 2008 or so.

My homework at that time revealed a couple of things:

1. Liquid crystals are individually driven by AC waveforms, not DC as one might assume. This is the nature of the beast. The frequency at which the signal alternates is not necessarily very high. Thus, sometimes, this alternating nature is visible.

2. Some displays use dithering. A given display might support just -- say -- 6 bits per subpixel. To get the full 8 or 10 or whatever number of bits that are expected as a final output, the in-between steps are approximated by switching between two values -- sometimes (again) at a fairly low frequency that is visible.

...

But anyway, that ViewSonic monitor: Most people thought it looked fine, but it drove me nuts.