Make Way For LPTV
By Pallab Chatterjee
As a follow-up to the recent California legislation to impose new energy standards on large screen TVs, most of the flat panels on display at the Consumer Electronics Show this year were on a significant energy diet. To get into the thin form factor, the biggest power draws of the backlight schemes had to be changed.
Samsung’s LCD division demonstrated a number of power savings methods that were similarly implemented by other TV manufacturers. The first area was with traditional CCFL backlight products. Samsung changed the light channels in the set to allow two CCFL bulbs to provide the same brightness and intensity as previous six-CCFL bulb models. There was also work done on the power reduction for “RGB” reference displays that produced 100% Adobe colors. For these models, a reduced bulb set and different power management was used to provide some power savings while maintaining the true color display.
The big buzz has been around “LED” TVs. These are actually LCD flat panels, with LED backlight systems. Some of the models replace the six-CCFL array with a full array of LEDs that cover the back of the panel. In addition to the increased product life, you also get a tremendous power reduction. The big enhancement to these products was the addition of data-sensing circuits that turn these LEDs on and off depending on whether the LCD is displaying light or dark information.
Some of the very-low-power displays have eliminated the full sheet of LEDs and replaced them with edge-based LED strips. These sets have either two strips on opposite sides, or four strips – one on each side. These behave similarly to the two-CCFL backlight designs and are starting to incorporate the data-dependent dynamic control circuitry that will turn tiles of the light on and off to both reduce power and increase contrast.
These enhancements also will be implemented into the 3D models, including the lenticular, glass-free sets targeted for digital signage as they progress in features.
Tags: Samsung