Lowdown on LED LCD Monitors

Slowly but surely, after LED backlights have taken over notebooks' screen lighting responsibilities, we are seeing them appear more frequently in every LCD monitor brand's latest endeavors. LED backlights claim better contrast, and moreover better power efficiency, than the regular CCFl backlights, that used to be the norm for LCD screens.

One thing about LEDs that is different from CCFL backlight is that the latter can diffuse very well, to show different levels of brightness. But LEDs use Pulse Width Modulation to show that they are dimming in brightness, meaning that the light actually is emitting at its full brightness whenever on, and to actually show different levels of brightness, the light is put on and off at fast flicker rates. So if you need a darker image, it is put off for longer periods. But of course the human eye cannot see this happen, it’s all above the fusion threshold of the human eye. These are 3 of our favorite LED-lit LCD monitors released in the very recent past.

Winner : BenQ V2200 LCD Monitor (LED lit)
Rs. 14,999

This one is a clear winner due to a number of factors. I agree it does not have any fluff in the form of webcam and speakers, but pure contrast wise none come close to this. The detail and sharpness also are on a higher level altogether. A few points need mention here - Colors were spectacular, but wasn’t theoretically perfect, as all the 3 channels in our color pluge had merging issues in highest intensity bars. This again is directly related to the backlight baring overpowering luminance to the shades. Thus one needs to actually reduce the brightness to below 50, to get the deep blacks and well gradated whites. Connector-wise we have a single HDMI in, and a VGA in, no DVI. This too is odd, and surely is a cost cutting tactic. This model has a screen size of 21.5 inches, and a native resolution of 1920 x 1080. The slim bezel makes it look wider, actually, but it’s a true 16:9 aspect ratio. The LCD panel itself is assumed to be a TN panel. Brightness is rated at 250 Cd/m2 but one must remember that the backlight is an LED backlight. Response time is 5 ms. The contrast is rated at 1000:1, and the dynamic contrast is rated at 5,000,000:1.