Sony Develops 4,032ppi OLED Micro-Display
tech.nikkeibp.co.jp
tech.nikkeibp.co.jp
And it seems Micro LED will be better fit for these type of application, where you have 0.5" of screen space.
What improvements are needed to increase OLED sales? PPI is at the top of my list because it's a necessary condition for VR to go mainstream.
>What improvements are needed to increase OLED sales?
Too expensive. Along with colour accuracy over time, burn in etc. All of them are not really solved ( yet )
Here's one: The US Air Force has estimated that a computer screen would require 10,300 pixels per inch to simulate these so called "hyper acuities". https://www.theregister.co.uk/2018/01/16/human_limits_of_vr_...
Actually, that's a pretty interesting article, posting a bit more:
But in one respect VR still lags far behind our biological limits: we are nowhere near a pixel density that mimics real life.
In theory, in our fovea, we need about 120 pixels per degree of view to match reality (although Meese [Tim Meese, professor of vision science at Aston University] says in practice, people generally can't see in finer detail than around 80 pixels per degree). Currently, the best headsets manage about 10 pixels per degree horizontally. Given the need to scale up by a factor of about 10 – on both axes – the increase in resolution required is enormous. "I don't think the technology is there yet for those display pixel densities," says Bryan William Jones, a retinal neuroscientist at the University of Utah.
And for VR obsessives who will settle for nothing less than a perfect replica of reality, even 120 pixels per degree might not be enough. Put two lines above each other and move one slightly to the left or right, and it turns out we are "extraordinarily sensitive" to even the tiniest differences between them, says Meese, even to movements smaller than the width of a cone in the eye.
To match this sensitivity on a computer monitor would require a pixel density that "beggars belief", he says, and well beyond 120 pixels per degree. The US Air Force has estimated that a computer screen would require 10,300 pixels per inch to simulate these so called "hyper acuities". This is more than 30 times that of an iPhone 7 (and 12 times the density boasted by a new Samsung VR display, revealed in June, which has a display of around 850 pixels per inch).
Such fine-grain vision is rarely used in the real world, says Meese. "The closest example you can think of is threading the eye of a needle, or something like that," he thinks. But it serves as a reminder that imitating the look of real life in VR remains a technological pipe dream – don't expect to do any VR sewing in the next decade or two.
I'm thinking we will see VR sewing in the next decade, because we'll find shortcuts to making it work. Sure hyper-acuity is hard, but its virtual reality, as long as you can make it look real it may as well be.
What I mean by that is - perhaps we could use tricks like stacking high-density screens which capture different portions of the pixels. Say you've got 3 high res screens somewhere in the headset, and somehow they are routing to the eye. With optics a high resolution screen can be made even higher resolution but smaller. It still is a very difficult problem to solve for sure, but I think if there are multiple difficult problems to choose from, chances are we'll find ways to partially solve some, combine that, and have something like a solution as a result.
With 3 screens you could have full scene for one, focused region on another, and fovea on another, and then optically stack that...somehow.
The primary issue with large displays is the failure rates during manufacturing.