Research On The Improvement Of The Target Light Effect Of LED In The University Of California

- Jun 12, 2018-

Research staff of the University of California, Santa Barbara, solid-state lighting and energy center SSLEC announced the a breakthrough study, the fluorescence powder can be improved, so that led lighting brighter and more efficient. The researchers said, their goal is to light efficiency reached 90%, or 300 LM / W.

Together this breakthrough research personnel, including the University of California, Santa Barbara, Department of material and chemistry and biochemistry system Professor ram Seshadri, materials science professor Steven denbaars and postdoctoral research associate Jakoah Brgoch.

Seshadri said that recent advances in solid-state lighting is a GaN LED. This technique in a large extent due to the University of California, Santa Barbara, materials science professor Shuji Nakamura, he invented the first high brightness blue LED. In solid-state white lighting technology, fluorescent powder is its application in such a way to the LED chip, photons emitted from the blue gan led through the fluorescent powder, mixed blue into green yellow orange light. When it is combined with blue light, green - yellow - orange light will give out white.

Recently, the preparation of fluorescent powder materials is more like an art rather than a science - the crystal structure acts as the main body of the activated ion, the high-energy blue light into a low energy yellow / orange light. Seshadri said: "so far, it has not been a complete explanation for what makes a number of fluorescent powder is effective and the other is invalid. In some not so good crystal, there will always be part of the photon into heat, resulting in waste."

"Little phosphor material retains its light effect at elevated temperatures," Brgoch said. "Very few people know how to choose crystals, which makes it more effective for fluorescent materials to play a greater effect and to maintain the light effect when temperature rises.

However, based on the calculation of the density functional theory, the rigidity of the crystal structure is the key factor to influence the efficiency of the phosphor. In addition, the structural stiffness of the index can be calculated by the density functional theory, then the fluorescent powder can be used for screening and then use. This breakthrough provides a "fast track for high efficiency and high brightness LED lighting". The elimination rate of low efficiency incandescent lamp and fluorescent lamp.

"Our goal is to achieve 90% LED light effect, or 300 LM / W, and we present the data obtained in the laboratory is 60%. Incandescent light bulb on the market is about 5%, the fluorescent lamp a little higher, about 20%." Associate professor and SSLEC of electronic and computer engineering, DenBaars, CO director, said.