Display Technologies Article Draft

[Zen00]

Hey all, I was hoping to get some crowd sourcing on this article I'm writing about LCD displays. I figured since I didn't know a lot about them, I'd go out and do some research on them. Here's a run on part of it about response times, something that I was confused about and hope to clear up for people. Let me know what you think. Where I can improve, different sources for the article, other points I could make, and so on. Thanks for your help!

Response Times

One of the most touted features on many of the LCD displays available today is the response time. Sometimes though it can be confusing just what exactly that means. With no definite standard of advertisement, slowly the market has worked its way towards displaying the GTG (Grey-to-Grey) time, rather than the true ISO (Black-to-White) measurement. A reason for this may be that many companies have managed to develop RTC (Response Time Compensation) technologies, sometimes called overdrive technologies, which accelerate the transition between grays. This allows the companies to boast an overall better time than their competitors. Some common names that crop up in the feature lists for a monitor, indicating RTC are ClearMotiv for Viewsonic, MagicSpeed for Samsung, and Over Driving Circuit for LG. For a more in-depth discussion of RTC, check out this link to TFT Central.

When you see an advertised response time, generally it will not say GTG, rather, it will just be the time posted in ms (milliseconds), typically 2, 4, 6, or 8ms. The real ISO is rather generally somewhere between 8 and 16ms, or about double the GTG. Take this with a grain of salt though, the better monitors can have much lower ISO than this, and sometimes that is what is advertised. You can see how confusing to the consumer this can be.

So then, what does a lower response time do for you? As shown in this, and this images, lower response times reduce the amount of smearing that occurs during fast action. A typical vendor demo will have two displays side by side, one with a fast response time, the other without. This will illustrate to the consumer the benefit of having the faster response time, though some studies have shown that if these same monitors are place in separate rooms the viewer will not be able to tell the difference. (Needs Reference) This effect may rise from the limitations on the human eye, which makes it unable to distinguish consciously the difference of a picture after it has reached about 60 FPS (Frames-Per-Second). This will translate into about anything under 10ms being undifferentiable to the eye. Most monitors on the market today will be able to easily beat this limit, thus making response times in the choice of an LCD display today almost a moot point.

Further readings can also be found here.

 

[Qdos]

If anyone needs sources of information on top performing monitors then the resources of TFT Central provide pretty decent reading material - especially on recent models, with the emphasis being placed towards PVA and IPS panels.

 

[Zen00]

Yes, I referenced them in the article.