New yellow fluorescent material can be made of the diameter of 10mm hemispherical white LED

Japan small silk production and research group at Nagoya University and the Tokyo Institutet of Technology professor Hosono Hideo Zebo research team developed a new yellow fluorescent material Cl_MS phosphor, mainly used in lighting with white LED. Vice president, director of small silk production technology, the minister responsible for the system of intellectual property goods room Planning Institute yokoya male two said, compared with the existing products, using Cl_MS phosphor for white LED "can get not only suitable for indoor lighting light, but also can reduce the cost". Specific production time is not announced, but the horizontal vector said, the production of fluorescent materials technology has been established, is working with LED vendors and lighting manufacturers to negotiate".

Quantum efficiency was 94%

Cl_MS phosphor is in the chemical formula (Ca1-x, Srx) 7 (SiO3) 6Cl2 on the mother of the crystal is responsible for the activation of the luminescence of Eu (EU) 2+, "with a layer of new crystal structure" (small silk production institute director Oga Kushi). Its characteristic is, with quantum efficiency of 94% will be converted into purple yellow light; blue light absorption excitation; luminescence spectra range, so the color performance of higher.

Small wire production using Cl_MS phosphor, blue phosphor and purple LED chip combination of the development of a diameter of 10mm of the hemispherical white LED. "It's a low concentration coating with a thick Cl_MS phosphor and a blue phosphor particle."". Compared with the existing white LED structure with the thickness of 2 to 3mm, the concentration of phosphor particles decreased to 1/10 ~ 1/20 (0.5mm).

White LED has five characteristics

The development of white LED has five characteristics. First, high luminous flux, bright. Compared with the original products of the same purple LED chip and phosphor, the luminous flux is increased by 25%. Because the phosphor particles are coated with low concentration, the light scattering and scattering between particles are suppressed. Second, the positive direction of the low brightness, reducing the white LED unique glare. Compared with the previous combination of blue LED chips and yellow phosphor (YAG) made of white LED, luminous flux in the same case, the luminous area increased to 10 times, the brightness down to 1/10.

Third, due to the use of two kinds of fluorescent materials to obtain white light light, so there is no directivity, although the diameter of the hemispherical structure of 10mm, white light does not appear uneven phenomenon. Using the same structure as the product, the blue LED chip and yellow fluorescent material were used to produce the white LED, and the results showed that the blue light had strong linear propagation and the surrounding part was yellow. In addition, the trial produced a purple LED chip combination of red, blue and green 3 color fluorescent material of white LED, due to the blue and green light is red fluorescent material absorption, so the surrounding red.

Fourth, by using the hemispherical structure with a diameter of 10mm, the irradiation range is larger than the original one. When applied to LED lighting, it can illuminate the whole room. Fifth, the high degree of freedom. Because there is no directivity, not only can be made into hemispherical shape can also be made of cone.

Cost is also very low

Small wire production by the use of part of the crystallization of raw materials as solvent (flux) of self melting method into Cl_MS phosphor. The processing temperature is about 800 DEG C. Due to the oxide fluorescent material, so don't need to be like YAG nitride fluorescent material, high temperature (2000 DEG C), high pressure (10 ATM), environmental control (oxygen) treatment, reduce the cost ("small silk production long).

The results of the study have been published in the October 16, 2012 (UK time) in the British "Communications" (Nature) magazine online edition. In addition, will be held in Kyoto in December 4, 2012, the exhibition will be displayed on the monitor "IDW 2012".