Flat Monitors

[Dean S. Messing]

: Could you post some info (or just your opinion) about LED backlights? 
:   Also, what's up with OLED technology?

Short answer:
LED backlight: The way of the future.

Longer answer:

Whitelight LEDs (used in HDR displays) are very bright but do not
allow spatio-chromatic modulation.  Individual RGB LEDs do, but their
quantum efficiency (roughly: ratio of luminance to power consumption)
is poor.

With an LED backlight, the thickness of the panels can (and will) be
reduced to 0.5 inches in the midterm future (just like Sony's OLED
panels).

LEDs are easier to "flash" than cold cathode fluorescents.  Flashing
removes the problem of "hold-type" blur that has plagued LCDs.  LCDs
are now coming out that run at 120 Hz and "flash" the frame on the
screen similar to a CRT  so their temporal characteristics are
excellent.

The big win is LEDs ability to be spatio-temporally modulated.  This
_dramatically_ increases the panel's dynamic range and contrast ratio,
which can exceed 100,000:1.  

With RGB LEDs one can get colour purity that is stunning.

Here's a useful article on this:

<http://www.luminous-landscape.com/reviews/accessories/nec-2180wg.shtml>

We have one of these in our lab and the colours (esp. green and red)
are, um, voluptuous.

It is somewhat dim compared to white light backlights but that problem
is going to be solved in the mid-term future.  Also this is an "old"
product.  The new NEC 2190 exceeds the specs of the 2180 and is
brighter.

OLED:

As for OLEDs, this is largely Sony's baby.  I saw their 20" OLED
panels at CES in January and they are beautiful in every respect.  But
they are still in the lab and Sony has not solved the aging problem
for the blue OLEDs.  On the other hand, high-end LCD panel
manufacturers are actively working on LCDs that will make Sony very
sad sometime soon. :-)

Have a look at:

<http://www.engadget.com/2007/08/22/sharps-52-inch-lcd-tv-prototype-just-1-1-inches-thick/>


Dean