Blue violet VS: LED white country winners?

"The use of blue LED white LED will disappear sooner or later. Nakamura Shuji in July 24th, held a speech on the GaN energy revolution seminar, said the speech, shocked the industry inside and outside. Nakamura Shuji had reason to develop a highly efficient blue LED and won the 2014 Nobel prize in physics, now actually has "overthrow" of this achievement, LED itself is blue defects, or out of the new Soraa main push purple LED propaganda? Will the next blue LED exit the stage of history? With these questions, interviewed a number of experts in the industry, one by one analysis.

In the village for the interests of the shareholders of the company?

LEDs is a narrow band light source based on semiconductor devices. The first LEDs emission wavelength ranged from infrared to green light. Blu ray LEDs will need to study the growth technology of high quality crystals, and the P doping control technology of wide band gap semiconductor, which can be realized in the GaN system at the end of 1980s. In addition, the research and development of high efficiency blue LED also requires the preparation of GaN based alloys with different compositions, and it needs to be incorporated into the multilayer structure of heterojunction and quantum wells.

The fluorescent material is excited by the blue light LED, and the green and red light will be emitted. In addition, with different complementary colors (red / Green / blue) with several LEDs can also be used to form white light. The above two technologies have been used in today's highly efficient electroluminescent white light source, and achieved significant energy saving effect.

But now Nakamura Shuji pointed out that, on the one hand, by the blue LED chip and yellow phosphor and white LED luminescence wavelength is not balanced, the peak strength and existence of blue light high, easily lead to sleep disorders, namely "blue".

On the other hand, the ordinary blue LED and fluorescent material composed of white LED does not contain uv. Therefore, compared with other light sources, including sunlight and ultraviolet light, there is sometimes a color difference.

As a result, Nakamura Shuji sentencing, the use of blue LED white LED will disappear, and pointed out that the United States Soraa sales of white LED is a solution. "

It is understood that Soraa is the village as co founder (co-founder) set up LED venture companies, mainly in the sale of purple LED chip combination of red (R), green (G), blue (B) phosphor white LED. This can not help but think of his remarks will be out of their own interests in the shares of the company?

In this regard, most of the LED industry experts said the possibility of higher.

WhichLEDs from the business point of view, that is in the village for their shares of the company may advertise. "The things that they invented are looked down on themselves, but they are very interesting. From the number of casualties in World War II, such as Mr. Nobel alive, but also should hate the invention of the TNT explosives. "

Vice chairman, Chinese Lighting Appliance Association of Nanjing University of Technology Research Institute of electric light source materials director Wang Haibo also said that this is not surprising, "background in the village said these words, naturally make people think it is for commercial purposes. "

Should look back, because he saw the prospect of purple LED, will invest in such a purple LED R & D Based company. It is not clear whether these remarks for the interests of the company. China rare earth expert group expert, China rare earth Association of light functional materials branch secretary general, Shanghai lighting society director Wu Hong suggested the use of reverse thinking about this matter.

The deputy general manager of Jiangsu Bo Rui optoelectronics Co. Ltd. Liang Chao believes that Nakamura Shuji is not for the interests of the company, "as a Nobel prize winning scientist, should be of high moral level and occupation ethics, for the decline of blue LED point of view, there is a theoretical support, of course, it is reasonable. "

Chen Zhenyi, vice president of the photoelectric crystal can agree with this view, "I believe he made his understanding and judgment should be based on the starting point. "

Purple LED obvious advantages?

Nakamura Shuji's speech is really out of the interests of the company, we can not make a conclusion, but it is now respected purple LED will really be replaced by blue LED, can be objectively analyzed.

Wu Hong, the prospects for the development of purple LED with positive attitude, "the purple light conversion white light with high efficiency, spectral distribution, color index is relatively good for energy saving and emission reduction, improve light quality has important significance. Although the impact of high prices, but also failed to spread, but the advantage is obvious. "

Specifically, what are the advantages of the white LED obtained through the purple LED?

1, high color rendering index. This white LED is a blue light that is excited by violet LED, and the peak intensity of the blue light is not too high. In addition, it can output all the light in the visible wavelength range, so the color rendering index is relatively high, can achieve the ideal white like the sun. And its red color index R9 is particularly high, the average color rendering index Ra is as high as 95.

2, high luminous efficiency.

(1) because the purple LED using GaN substrate manufacturing, purple LED chip fabricated in GaN substrate laminated GaN semiconductor, belonging to the "GaN on GaN" LED GaN, the crystalline quality of the semiconductor layer is relatively high, so the purple LED high luminous efficiency, and improve the efficiency of speed.

(2) the purple LED chip is a triangle, and the shape of the ordinary LED chip is of the shape of the four corner. Compared with that, the light emitted by the luminous layer of the triangular LED chip is compared