Higher Efficiency LEDs

[AardvarkSagus]

This can only be a good thing (via: Engadget):

Researchers develop higher-efficiency LEDs

by Nilay Patel, posted Jan 14th 2009 at 5:16AM
Terrific-looking LED-backlit HD displays were all over CES this year, and it sounds like they're only going to get better -- scientists from Renssalaer Polytechnic Insitute and Samsung have developed a new polarization-matched LED that cranks out 18 percent more light while being 22 percent more efficient than traditional LEDs. The improved performance is due to a reduction in "efficiency droop," which causes regular LEDs to turn less power into light when fed higher currents -- the team replaced the traditional active layer of the LEDs with a new specially matched layer. No word on when any of this is coming to market, but we're holding out hope for CES 2010.

Any comments? Is this tech going to spill into hi-power LEDs?

 

[brucec]

All LCD TVs have a polarization filter in them which cuts out 50% of the backlight right off the bat. This polarization filter is fundamentally required for the LC switching to turn a pixel on or off. It sounds like what RPI and Samsung did was create a LED which emits polarized light that can be matched to the filter allowing greater transmission. They can then reduce the current to the LED backlight, thereby increasing efficiency (22%) while retaining the greater brightness (18%).

For flashlights, these LEDs sound like they are producing LESS lumens, but the lumens they produce are matched to the filter polarization. You wouldn't be able to see any difference unless you were wearing polarized sunglasses. In fact, the LEDs are probably producing less lumens due to the lower drive current.

 

[DM51]

Belongs in LED, not LED Flashlights.

 

[AardvarkSagus]

Belongs in LED, not LED Flashlights.

Oops, had too many tabs open...

 

[AardvarkSagus]

All LCD TVs have a polarization filter in them which cuts out 50% of the backlight right off the bat. This polarization filter is fundamentally required for the LC switching to turn a pixel on or off. It sounds like what RPI and Samsung did was create a LED which emits polarized light that can be matched to the filter allowing greater transmission. They can then reduce the current to the LED backlight, thereby increasing efficiency (22%) while retaining the greater brightness (18%).

For flashlights, these LEDs sound like they are producing LESS lumens, but the lumens they produce are matched to the filter polarization. You wouldn't be able to see any difference unless you were wearing polarized sunglasses. In fact, the LEDs are probably producing less lumens due to the lower drive current.

The way I was seeing it, was that it would not only match the polarization which would improve transmittance (the 18% figure), but also improve efficiency at higher drive currents which is one of the curious effects of current LEDs. The lower the current, the better the efficiency. This new LED seems to counteract that somehow causing the 22% more efficiency.

 

[saabluster]

Already covered in this thread.