It’s certainly true that only a small handful of manufacturers actually make the LCD panels that go into them, which means there are recognisable levels of technological overlap.
Are PC monitors merely badge-engineered commodity items? It’s certainly true that only a small handful of manufacturers actually make the LCD panels that go into them, which means there are recognisable levels of technological overlap. Take for instance the fact that many of the current crop of affordable IPS screens share panels.
Occasionally a monitor manufacturer picks up a new panel before the competition. For example, Viewsonic seems to have stolen a march by upgrading its IPS 23-inch from 6-bit-per-channel colour to 8-bit.
What’s more, image processing electronics can make a difference, especially when it comes to colour dithering. We use the trusty Lagom LCD suite of test images and metrics to provide a common baseline. Handily, you can too, by popping over to www.lagom.nl. There are test images to help you assess everything from viewing angles to pixel response and colour fidelity.
If that’s the more objective part of the equation, there’s no substitute for some subjective immersion. That’ll be games, movies and just flicking about on the desktop. Sometimes a screen that doesn’t perform all that well in the objectives is still a very nice panel in practice.
01 Panel type
This is the biggie — the heart of your display machine. You’ve basically got three choices: TN, IPS and VA. TN is the cheapest and quickest in terms of pixel response. It’s also the best for pure gaming. For everyone else, IPS is the affordable option, offering superior viewing angles and colours to TN. Pixel response isn’t that far behind either, making it a tough sell for the TN panels. VA is the odd one out. It’s used fairly infrequently now, but offers better blacks and contrast than both TN and IPS along with colour fidelity and viewing angles that sit somewhere in between the two other technologies.02 Backlight technology
We’ve been waiting aeons for a dramatic change in panel technology, and yet it never seems to materialise. In the meantime, at least the backlight technology tree has been given a good shake. In the last few years, CCFL (cold cathode fluorescent) backlights have been almost entirely replaced by LED backlights. Almost every PC monitor is now LED.But not all LEDs are made equal. For starters, there’s the choice between white and RGB LEDs (or red-green-blue LED) backlights. The latter produce purer, cleaner light and allow a broader colour space. But they’re expensive and relatively rarely used.
03 Image processing
Manufacturers know that big numbers make a big impression when you’re in the market for buying a screen — numbers like 10,000 to one or even a million to one when it comes to contrast ratios, for instance. They sound impressive — all the more reason to choose one monitor over another, perhaps, but not the be-all and end-all. Little numbers work, too, like 1ms for pixel response. Many of these and more are made possible by image processing technology.Big contrast is achieved via backlight modulation, dimming the lights when dark images and video are displayed. Faster pixel response is done courtesy of overdrive algorithms that pump pixels with exaggerated voltages. The thing is, none of them are a substitute for a good panel. Strong contrast with a static backlight is always better than the dynamic sort. And overdriving pixels can lead to nasty side effects, like inverse ghosting.
04 Refresh rate
Forget stereoscopic 3D, the next big thing in PC monitors is 120Hz refresh. At least we think it ought to be. As it happens, the faster 120Hz refresh standard (most LCD monitors are 60Hz) only came about because it was necessary for active shutter 3D technology. But never mind that, because it’s here now and it’s lovely. Until you’ve seen the added smoothness and felt the increased response, it’s hard to really appreciate the benefits of 120Hz. But once you’ve seen it, you won’t want to go back to 60Hz. Unfortunately however, 120Hz technology is currently limited to screens with TN panels. We’re still waiting for the ultimate combination of 120Hz and IPS or VA.05 Video inputs
Now that we’ve all gone digital, surely video inputs don’t matter? Up to a point, that’s true. Indeed, the video signal used by DVI and HDMI is essentially shared, which is why those little DVI-to-HDMI adaptors are possible. But there are a few extra things worth factoring in. Screens with resolutions beyond 1,920 x 1,200 or with 120Hz refresh speed need dual-link DVI or an HDMI 1.4 port on your graphics card to pump all those pixels. And what about DisplayPort? It offers several theoretical advantages, including the ability to daisy chain multiple monitors in a serial setup. In reality, that’s a fairly unlikely usage scenario. As things stand, we’d pay extra for DisplayPort.Source
0 comments:
Post a Comment