I was reading an article on the new LG display with a refresh rate of 7680Hz and it says:
While a typical refresh rate for a monitor might be 60Hz-240Hz, an outdoor display designed to be viewed from a distance needs to be much higher
The idea that there’s an intrinsic link between refresh rate and viewing distance is new to me and feels unintuitive. I can understand the need for high brighteness for far view distance. I also could understand refresh rate mattering for a non-persistent (CRT) display. But for an Led display surely you can see it far away even if it refreshes once a second?
Refresh rate normally needs to be high enough to avoid pixels “jumping” between refreshes on high resolution displays, so wouldn’t higher view distances allow you to decrease the refresh rate?
Is the article just spouting bullshit? Or is there an actual link between refresh rate and view distance?
My guess is there’s been a game of telephone with the information.
The refresh rate likely refers to the drivers of the individual LEDS making up the panel.
For those confused, getting a nice linear output from an LED is extremely difficult. They vary significantly based on age, use, and manufacturing tolerances. It’s far easier to just set a max output, and use PWM. By combining 3 (or more) LEDs in a cluster, you can make the full mix of colours and brightnesses available.
Most generic led drivers work at a few khz, so 7.68khz is noticeably higher than normal. This is particularly important at low brightness. If your operation in the bottom 1% already, your available brightness levels go from 20 to 768. This would be particularly important with an outdoor screen. In daylight, you need a lot of output. The same output at night, however, would be blinding.
For an alternative comparison. An HD 50p video signal is 3Gbps. At 7680Hz it would be 460Gbps, an extreme ask of any sort of network. For no significant gain.