Objective to improve the luminous efficiency of LED in California 300lm/w

Center for solid state lighting and energy Santa Barbara branch of California University (SSLEC) researchers announced a groundbreaking study, can improve the fluorescent powder, make LED lighting brighter and more efficient. The researchers said that their goal is to achieve light efficiency of 90%, or 300 lumens / watt.

For this breakthrough of research personnel including California University of Santa Barbara Department of materials and Department of chemistry and biochemistry professor Ram Seshadri, Professor of materials science Steven DenBaars and postdoctoral associate Jakoah Brgoch.

Seshadri said the latest progress in solid-state lighting is Gan LED, this technique is attributed to the California University in Santa Barbara, Professor of materials science Shuji Nakamura to a great extent, he invented the first high brightness blue LED. In solid-state white lighting technology, phosphors are used in such a way as to the LED chip - from blue gallium nitride LED photons through the phosphor, the blue light into a green - yellow - Orange range of light. When it is combined with blue light, green - yellow - orange light will emit white light.

More recently, the preparation of phosphor materials is more of an art than a science - the crystal structure acts as the main activating ion, transforming the high - energy blue light into a low - energy yellow / orange light. Seshadri said: "so far, there is no complete explanation of what makes some phosphors work and others do not work. In some not so good crystals, there will always be some photons into heat, waste. "

"Very few phosphors still maintain their light at elevated temperatures," Brgoch said. "Little is known about how to select a crystal that makes the fluorescent material more effective and still maintains a light effect at elevated temperatures.

However, based on the density functional theory, the researchers determined that the rigidity of crystal structure is the key factor that affects the efficiency of phosphors. In addition, the index of structural stiffness can be calculated by density functional theory. This breakthrough provides a "fast track for high efficiency and high brightness LED lighting". Inefficient incandescent and fluorescent light bulbs to further accelerate the elimination rate.

"Our goal is to make the LED achieve a 90% light efficiency, or 300 lumens / watt, and we are currently in the laboratory to obtain the data is 60%. Incandescent light bulbs on the market is about 5%, a little higher fluorescent lamp, about 20%. DenBaars, Professor of electrical and computer engineering and co director of SSLEC, said.