OLED's an Even Greener LED
There are lots of reasons to love LED lights.
They are good for the planet.
You don't have to replace that bulb in your flashlight every few months.
You don't get that ugly yellow tinge to everything.
The only problem is that you cannot enjoy LED lighting in your home, at least not yet.
Researchers are closer to flipping the switch on cheaper, richer LED-type room lighting.University of Florida materials science and engineers have achieved a new record in efficiency of blue organic light-emitting diodes, or OLEDs. Because blue is essential to white light, the advance helps overcome a hurdle to lighting that is much more efficient than compact fluorescents — but can produce high-quality light similar to standard incandescent bulbs.
OLEDs are similar to inorganic light emitting devices, or LEDs, but are built with organic semiconductors on large area glass substrates rather than inorganic semiconductor wafers. When used in display screens computer monitors, they have higher efficiency, better color saturation and a larger viewing angle. OLED displays are also used in cell phones, cameras and personal digital assistants. OLED flat panel TVs were introduced by Sony recently.
So and his team’s blue OLED achieved a peak efficiency of 50 lumens — a lumen is a measure of brightness perceived by human eyes — per watt. That’s a significant step toward the goal of his project: to achieve white light with efficiency higher than 100 lumens per watt.
So said the fact that OLEDs are highly “tunable” — each OLED is an individual light, which means differently colored OLEDs can be combined to produced different shades of light — puts warm, rich light easily within reach. “The quality of the light generated can easily be tuned by using different color emitters” he said. “You can make it red, green, blue or white.”