zaiblog | The truth about LCD monitors

The truth about LCD monitors

In the hunt for a new LCD? Know more about contrast ratios, response times, panels, makes and all those numbers and terms.

Okay, here’s the story, a fellow got a new LCD. We then decided to compare it with my “old” LCD, just to see which one performs better. On paper, the new LCD seemed far more superior than the old one — because of higher specs and more features. Guess which one did it better…

It’s a tie. Both had the same image quality. Why is that, you might ask? Here’s some specs:

New LCD:

Up to 1920×1080 resolution, 5 ms response time, 16:9 aspect ratio, 20,000:1 contrast ratio, 16.7 M colours

Old LCD:

Up to 1440×900 resolution, 5 ms response time, 16:10 aspect ratio, 1,000:1 contrast ratio, 16.2 M colours

For better comparison, we shall call “new LCD” as LCD A and “old LCD” as LCD B from here on.

LCD A had .5 M colours more, a higher maximum resolution, wider aspect ratio and higher contrast ratio — how come both displayed the same image quality?

The answer: most manufacturers, these days, tend to “overwork” their advertised specs — which is a little similar to the way bankers make credit out of thin air. A good example is contrast ratio or the deviations of brightness and darkness in any given image or output. LCD A has been advertised to be capable of 20,000:1 contrast ratio, but in reality, it could be 1,000:1 as well. The 20,000:1 figure is just the “dynamic” contrast ratio or some consider it as “bursts” of contrast.

So, do contrast ratios indicate better image quality? No, and vice versa. Oh, this monitor has higher contrast ratio so it must be better. As a yardstick, general film prints and theatres have 500:1 only. Another thing to consider is how manufacturers quantify contrast, see this and this for more info.

Moving along, the real advantage of LCD A is obviously the higher maximum resolution and larger colour palette. But then again, 16.2 M versus 16.7 M? Can we even see the difference? Of course there’s 500,000 in between, but most users can’t even distinguish burgundy from crimson.

But if you’re indeed serious about colour and quality, here’s a list of panel types:

Twisted Nematic (TN)

- most common LCD type, widely available
- cheap price and fast response times
- saturated colour palette and limited viewing angles
- mostly used by gamers

In Plane Switching (IPS)

- better colours and viewing angles than TN
- slower response times
- pricey, rare

Super-IPS (S-IPS)

- improved IPS
- superior colours and faster response times
- less expensive than IPS but still quite rare
- best for colour intensive tasks

Multidomain Vertical Alignment (MVA)

- basically in between IPS and TN
- better colours than TN
- better viewing angles than TN
- superior contrast
- average response times
- medium price
- all-rounder
- will replace TN in the future

Speaking of panels, some brands use panels from other manufacturers. Some Samsung LCD monitors are from Chi Mei Optoelectronics and AU Optronics. While LG supplies to Apple and Dell, and Sony has joint-ventures with Samsung and Sharp. There are more details about this, just google it, I guess. If you want to save some bucks then you might as well go directly to the “source”.

It’s a lot easier to buy an LCD monitor today because most models have come to a point wherein they all boast an identical set of features. For example, a lot we can buy today would have an HDMI port and less than 10 ms response time. It would just be a matter of budget, warranty, availability and brand preference. To conclude in brief, we should be looking more into panel types when purchasing. Simply because panels can make or break performance and image quality. Calibration is another thing to look upon, even a simple adjustment of brightness and contrast can help. And lastly, using HD content will always show your LCD’s full potential.