The LED LCD Revolution Continues
In January, I wrote about the eye-opening trends on ‘Display’ at the Consumer Electronics show in Las Vegas, and described the incredible thinner and lighter form factors enabled by LED backlit LCD TVs. Now I would like to talk more comprehensively about why this revolution in TVs will be so attractive to consumers.
Compared to the "traditional" CCFL (cold cathode fluorescent lamps) backlit LCD TVs (if any product that’s only been available for around five years can be called "traditional"), LED backlit LCDs provide a significant extension of the benefits consumers enjoyed with LCD TVs vs. even more traditional CRTs (,cathode ray tube technology first commercialized in 1922 by Western Electric) and PDP (Plasma Display). LED backlit models improve (1) image quality, (2) industrial design, and (3) "Greenness" (lower power and less heavy metals) compared to traditional LCDs.
Figure 1 below summarizes these benefits.
The design elements, or "SAF" ("Spouse Acceptance Factor"), are improved, because the LED backlights enable much thinner and lighter set designs, so 55" and larger screen sizes at less than 1" thick are no longer the things of science fiction. These thin designs look better, and are lighter and easier to set up or hang on the wall.
Image quality, as measured by black level, motion picture response time (MPRT), or even contrast ratio, can actually be improved by a factor of up to 10X with LED backlighting. This contrast ratio improvement is achieved by "local dimming", where sections of the backlight are turned off, or dimmed, in areas where the displayed image is dark. Standard CCFL backlights, on the other hand, are always on across the entire area of the screen when the set is turned on (light selectively blocked by the liquid crystal "shutter" creates the RGB image).
This relates to another improvement with LED backlights, reduced energy consumption. Besides the inherent light creation efficiency of LEDs (in lumens per watt) compared to CCFLs, the ability to turn off the light behind parts of the screen, where a dark image is displayed, leads to additional power savings. The combination of these two attributes leads to ~50% power savings for any given screen size, significantly offsetting what was one of the few downsides of the rapidly growing installed base of ever-larger TVs worldwide.
The Expected US TV Energy Consumption chart, shows the annual energy consumption increase for the U.S. for TVs alone, as forecasted back in 2006.
With the growing demand for TVs, and trend for ever-larger screen sizes, consumption was expected to grow from an already enormous 53B kWh in 2006 to 70B kWh in 2009. The growing energy consumption by TVs led to stricter Energy Star and related standards limiting the on-mode power consumption of TVs in addition to the standby power mode, which was previously limited by Energy Star. In fact, the National Resource Defense Council estimated that by shifting from Energy Star 3.0 to 4.0, could save over 40B kWh of energy per year within a decade. LED backlighting in LCD TVs will play a significant role in making TVs in the U.S. compliant with Energy Star 4.0, and thus globally LCD TVs will save more energy and be more compliant with new energy standards in Japan, Europe and China.
One last very green aspect of LED backlights in LCD TVs is that they do not use any mercury, as CCFL backlights do, so manufacturing and disposal are better for the environment as well.