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Making LCD Displays Snappier
newSlashUser points out a very interesting article at ExtremeTech about a new means of more quickly
controlling LCD panel response, so the old complaint that LCD panels make poor displays for gaming and high-motion video may be whittled down a bit. As a bonus, the change is all in the controller, so it doesn't require any change in the way the panels are manufactured.
If you can get your LCD controller to run at 60-80Hz, you should be able to implement this technique in software: compute change-corrected frames, where the ``feed-forward'' bits disappear faster than the human persistence rate. There's plenty of CPU for this, and the psychovisuals help: any reasonable transient errors in the LCD response are likely to be masked by the fact that the changing pixels are likely changing due to motion...
I had always just sort of assumed that controllers already did this, since it's so obvious. Even better would be to have the controller actually measure the pixel modulation (which it it should be able to do using the same mechanism it uses to change it) and use feedback, which would likely provide even faster response.
Sadly, at the end of the day, the 40Hz limit on skewing reasonably priced panels over the full range will continue to be a problem. With feedback and feedforward techniques, can one use higher pixel modulation voltages to improve this as well? I don't know, but I would guess one could...
Apple's LCD displays are probably the best that exist, beating out SGI by a large margin. I've never had a moment's problem playing Quake or Unreal Tournament on my TiBook or G4, using either the Studio or Cinema display.
Perhaps the solution isn't more hacks, but better hardware. Sure, it comes at a price, but I'd rather drop an extra couple hundred for something that actually works.
Hippies smell.
My time spent with Philips Flat Displays in Philips Components allowed me time to see this and many other LCD-ish technologies. If you look here at the papers about Motion Compensation, that is the stuff I saw, and in fact, our group was working on the drive electronics to make it work. David Parker, one of the authors on a couple of those papers, is a very cool guy, as were all of the guys at PRL in Redhill, England.
Unfortunately, the LCD panel business slipped into commodity mode too quickly, where 15-inch panels and the displays containing them had to be super-cheap, and that was where Philips wanted to be, so we tabled the project. The simulations, though, showed a drastic difference is clarity and response time, resulting in sharp images suitable for television or video gaming.
As an aside, someone asked about applying voltage to get black. This works best with active matrix displays, while passives use the normally-black approach (apply voltage to get white). If you remember your old laptop displays from back then, dark vertical lines in dialog boxes and the like created vertical lines that ran the height of the screen thanks to voltage leaking to all of the dots in a column, which is not a big problem for actives.
There is a lot of cool stuff in the future of displays. LCD tech of today sorta sucks/ Look for some very cool stuff in multidomain displays and OLED/PolyLED displays.