LG is not sitting back and letting the competition get ahead in VR technology. In a US patent application granted last week, it appears the the South Korean company has technology that combats the “screen-door effect” of VR screens.
The screen-door effect refers to the annoying experience in VR where users can see the gaps between the pixels. Technically speaking, it is when a light-blocking area between the sub-pixels of a display panel is clearly visible. Think of it like a lattice resembling a mosquito net. Obviously, this does a lot in taking away immersivity.
While a higher resolution display can alleviate the screen-door effect, it will also drive the price of the headset higher. LG’s solution is much more elegant and instead uses a “light diffusion member”. This goes in between the display panel and the lenses.
For those whose introductory Optics courses were a while ago, diffusion is the process by which light is scattered as it passes through a medium. LG's newly-patented “light diffusion member” won't do this as aggressively as, say, the frosted glass on a light bulb, but it is basically attempting to counter the screen door effect with a soft focus filter.
This might work, of course, and it is a cheaper alternative to higher-resolution displays, but I have a more fundamental question, here: is the screen door effect really such a problem that it's worth degrading the image resolution of VR displays to solve it? Because here's the thing: while the screen door effect is an actual thing, it's actually not all that noticeable in practice.
This is because of a quirk in the way your brain processes visual information. Your brain, it turns out, isn't all that interested in stuff that isn't moving or changing. In the same way that streaming videos don't push thirty complete images to your device every second, instead just telling your computer which pixels in the image are changing from frame to frame, your brain is only watching for changes in your visual input stream. Any element that's not moving or changing quickly ceases to be of loses interest, and your brain starts to ignore it.
If you're reading this on a screen using your eyeballs, then you're seeing this effect in action right now... and I can prove it to you.
Q: When was the last time you really noticed your own eyelashes?
Your eyelashes are always there, between your eyes and the world, and they're always visible, but you probably didn't actually notice them until I drew your attention to that fact. While your eyelashes are always there, and always visible, they don't actually change much from moment to moment, which makes them boring, and so your brain ignores them. It's like a Hollywood studio painting something out of a frame in post-production, except done in real time, all the time, from the moment you open your eyes in the morning.
And I can tell you from experience that the same thing happens with VR's screen door. When I first tried on a VR headset, I knew about, and was watching for, the screen door effect; I wanted to see how pronounced it was, and whether it would prove irritating enough over time to ruin the VR experience. But while the screen door was visible, it wasn't interesting, and my brain had started ignoring it as soon as I started concentrating on something else.
In some ways, this is the polar opposite of the VR sickness issue. With VR sickness, the display technology sends signals that conflict with the information coming from your inner ear's vestibular system, with effects which can range from disorientation to projectile vomiting, and which can persist for twenty or thirty minutes after you take the VR headset off. There is no technological fix for VR sickness, either, because the problem isn't the technology, per se; instead, the issue is human biology, which VR hardware developers can't alter.
But with the screen door effect, human biology actually comes to VR's rescue, compensating for this limitation of the technology automatically, and for free (#YourBrainIsAmazing).
Which brings us back to LG newly-patented “light diffusion members.” Yes, they might compensate for the screen door effect, and do so more cheaply and simply than increasing the resolution of the displays in the headsets themselves, but "LDMs" are still more expensive, more complicated, and heavier than the highly effective alternative which VR customers already have built-in. LG's new doohickey is a solution to a problem that doesn't exist, and will add cost, weight, and complication to any device which includes them... at a time when VR hardware developers are trying desperately to reduce all three of those things.
The screen door effect doesn't need a technological solution. Maybe LG should be more focused on VR other failings, like the fact that VR still doesn't enable any quantitatively different activities at all.