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KaiserPro • today at 2:14 PM • 6 replies • view on HN

Ok but who can actually see 240hz?

Like CRTs scan slower than that, and almost no-one could say they could see the pixels being drawn.

Sure you could hear those fuckers, but not see them, unless you had a source of vibration nearby.

Howe much of this is measurable, and how much of it is similar to the Himalayan salt lamp stuff?


Replies

mrob • today at 2:55 PM

The problem isn't the flicker directly (240Hz is above the flicker fusion threshold), it's the phantom array effect when you move your eyes. Static images transform into a series of overlapping images, and this can be annoying and distracting. It's visible well into the kilohertz depending on how strong your saccadic masking is. I can personally see PWM up to about 10kHz (tested using a strobing LED).

AFAIK, all OLED displays have PWM flicker, and for this reason I stick with LCD, where flicker-free displays are available (although PWM flicker is present in some LCD displays too).

rayiner • today at 2:30 PM

I can easily see at least some PWM LED headlights flickering in my peripheral vision (which is more sensitive to flicker).

Y-bar • today at 2:18 PM

Fluorescent tubes used to run at less than 100 Hz before scientists discovered that that was unhealthy for many. Now they run at 30-60 kilohertz.

LoganDark • today at 2:18 PM

It's not about whether you can "see 240Hz". CRT phosphors have sustain, while OLED does not. The fully-on, fully-off cycle, if infrequent enough, causes some sort of visual stimulation that some brains absolutely do not like. You don't have to see it to feel it.

Sometimes I can tell flickery fixtures because they just "feel more staticky". I don't get visual eyestrain or nausea though.

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