HACKER Q&A
📣 meristohm

What screen resolution is enough for most humans?


Given that higher resolution screens cost more electricity (ceteris paribus), and that we have accuity and process-rate limitations (across a distribution throughout humans), what resolution is a reasonable “soft-stop” beyond which few people will benefit (acknowledging aphakia and other eyesight conditions) and we can spend those resources on greater gains?

I’m comfortable with the pixel density of my 21” 1920 x 1080 monitor, though I’m not staring at it for more than two hours at a time. An upgrade costs money and resources. Perhaps I’m misplacing my concern and The Market will sort it out, but it feels like part of a broader question of “what degree of improvement is too far?” with regards to reducing our collective influence on earth’s climate.

  👤 kwdc Accepted Answer ✓
For me, ideal pixel density is when I can draw a 45 degree line with high contrast, eg white on black, and there are no blocky pixels visible. No stepping at all. Even better is the density where pixels effectively disappear altogether. Same for any other angle.

Aspect ratio also matters. I should be able to take a square and rotate it and it shouldn't change shape. Measurable using a physical ruler for best results. It doesn't sound like a big deal until you rely on it. I'm sure theres a research paper about this effect contributing to fatigue.

Refresh rate and lighting are also important factors. 60hz was a gimmick for me until I got a setup that could maintain it. Originally I figured it was no big deal but now I actually notice when I use a lesser setup of monitor and computer. Its a different experience. Its not a sense of "this is wrong", more like "this isn’t as snappy". Not as responsive.

At around 40", I find 4K on a monitor is "fine" but there can still be some stepping. At lower screen sizes, 4k for me is "excellent". I think 8K or similar at 43" would achieve the "no jaggies whatsoever". Maybe even less pixels would suffice. BTW I'm not talking about setups where you sit away from screen like a TV watched from a couch.

👤 addaon
Are you assuming uniform pixel density? A typical eye has ~1e8 rods, but they're very much not uniformly distributed. If you can place each "pixel" perfectly (for example with a retinal projector), you can get away with only a hundred million pixels or so; but if you want a uniform grid, then you need the pixel spacing to match the maximum angular acuity of the eye, which is several orders of magnitude more pixels.

In either case, we're a few orders of magnitude off with current displays, although you can gain as much of that back as you want by reducing angular extent ("screen size").