I’ve been greatly enjoying following the progress of visual fidelity over the past 15 years. For such a long time TVs were just TVs, and most people never really thought about them changing. But, of course, ever since 720P/1080i HDTVs hit store showfloors in the late 90s advancements have been happening at a staggering rate.
For a while now it seemed that 8K would be the resolution endpoint for the popular television sizes (mainly due to the fact that NHK and others set 8K as the goal as far back as 2003). And for tablet sized devices on down it seemed that 8K would be more than sufficient to reach “retina” status.
But when we’re talking about virtual reality, even an 8K-by-8K screen isn’t enough pixel density to create true verisimilitude.
Oculus VR founder and CEO Palmer Lucky recently explained why this is so in an interview with Ars Technica. In short, the reason is thin diagonal lines:
“There is a point where you can no longer distinguish individual pixels, but that does not mean that you cannot distinguish greater detail. You can still see aliasing on lines on a retina display. You can’t pick out the pixels, but you can still see the aliasing. Let’s say you want to have an image of a piece of hair on the screen. You can’t make it real-size… it would still look jaggy and terrible. There’s a difference between where you can’t see pixels and where you can’t make improvements.”
Since 16K+ resolution would be necessary for perfect VR, it follows that a perfect “life wall” (a screen that doubles as a wall in a room that can display any desired scenery) would need to be made out of thousands of 16K-by16K head-mounted display sized screens tiled together. That’s an obscene amount of K’s.
Luckey also explains why 8K resolution in screens of the small size required for a head-mounted display will be possible 10 years from now:
“To get to the point where you can’t see pixels, I think some of the speculation is you need about 8K per eye in our current field of view [for the Rift],” he said. “And to get to the point where you couldn’t see any more improvements, you’d need several times that. It sounds ridiculous, but HDTVs have been out there for maybe a decade in the consumer space, and now we’re having phones and tablets that are past the resolution of those TVs. So if you go 10 years from now, 8K in a [head-mounted display] does not seem ridiculous at all.”
The article’s top comment calculates that “perfect” VR for someone with 20/10 eyesight would require a display with 108,000 horizontal pixels, or 108K per eye, which is significantly higher than most estimates I’ve read (most calculations fall somewhere between 8K and 32K).
There’s also an in-depth discussion about resolution over at the Oculus VR developer forums. And, for a slightly more pessimistic take, Valve’s Michael Abrash has a blog entry arguing that 8K screens aren’t just around the corner.
You can read more about some of the various criteria that scientists/engineers have come up with to figure out the limits of the human eye at this page over at 100fps.com.
And it’s always good to get a reminder of how amazing “mere” 8K resolution is (and keep in mind that this video shows an 85-inch screen!):
Here’s some recent HFR Movies coverage of the march towards an 8K world: