LED standard development into the fast lane

LED focus on trial standards is a major event this year in the lighting industry. In a total of 19 trial standards, the Ministry of LED lighting technology standards working group undertook the research and formulation of the 7 criteria, involving many aspects of LED chip, device, module, module etc.. Recently, the reporter interviewed the Secretary General of the standard working group, China Institute of Electronic Technology Standardization Institute, senior engineer Zhao Ying, asked her to develop a comprehensive description of the standard.

Reporter: would you please briefly introduce the ideas and the overall framework for the development of standards.

Zhao Ying: LED lighting standards working group since its establishment in 2005, is responsible for the formulation of relevant standards. Standard working group has 57 Members, covering the industrial chain of chip production, device packaging, phosphor preparation and application of product manufacturing and other fields of the unit.

Our overall idea is based on the standard products in the industrial chain of the middle and lower reaches, divided into 4 sub areas: "1" includes various types of materials and raw materials, epitaxial wafer sub areas; 2 "including midstream chip, device, module / component and LED drive circuit and control circuit; application of" product field 3 "is mainly related to LED; test equipment manufacturing, testing, as the" 4 sub fields". The construction of each sub standard system is based on the characteristics of the "basic standards", "product standards", "process technology standards", "safety standards", "management standards" in these 5 categories.

Reporter: this year the working group submitted to the approval of the 7 criteria, which are mainly involved in the field of content? What are the specific criteria? What are the breakthroughs?

Zhao Ying: so far, the working group has developed 9 industry standards, last year, there have been two standards to complete the approval, this year is the approval of the standard has 7. These standards are mainly concentrated in the LED industry in the upstream, including: power semiconductor optoelectronic devices, blank detail specification for light emitting diode semiconductor light emitting diode test method (revision of SJ/T2355.1 7:1983 semiconductor light emitting device testing method, semiconductor lighting terminology), GaN based light emitting diodes with the sapphire substrate, the semiconductor light-emitting diode with phosphor, power semiconductor light emitting diode chip specification, semiconductor light-emitting diode chip testing method, semiconductor optoelectronic devices - Blank detail specification for small power LED, semiconductor light-emitting diode product series spectrum. The development of these 9 standards, to improve the semiconductor lighting sub domain, the standard system has played a significant role in regulating the market played a certain role in the protection of.

These 9 standards are developed independently, in some areas have a breakthrough. For example, in the semiconductor light emitting diode with fluorescent powder in the standard, first proposed the "external quantum efficiency" instead of "relative brightness" as indicators of luminous efficiency evaluation of fluorescent powder, and formulated the "test method of external quantum efficiency". In this way, the powder selection work is simplified in the test, and the problem of difficult to test the luminous efficiency of phosphor has been solved for a long time.

Reporter: LED has been applied in many areas, but the application in the field of lighting began in the past two years. So what is the difference between the LED standard and other standards?

Zhao Ying: LED applied to display, indicating the field had already been the standard introduction, but the focus of the standard lighting and the development of different. LED is used to indicate and display the main indicators of the assessment is wavelength, for the purpose of lighting to assess the color coordinates, color temperature, etc.. In the past, small power device does not have high requirements on the heat, but with the change of market demand, now gradually to use high power devices, heat directly affects the life of the product, and therefore also on the heat dissipation test of thermal design, power consumption, energy efficiency assessment, these are formulated LED lighting standard focus.

In addition, due to the specificity of the LED, it's standard setting and other lighting products are also different. For example, the life of the LED assessment method is different from ordinary lighting. At present, we are trying to use the accelerated life test method, under certain stress conditions, through the calculation of data accumulation extrapolated life. In short, the development of lighting LED standards compared with the previous standard development work is still very different.

Reporter: we know that the development of standards is a very complicated process, during which difficulties and problems encountered?

Zhao Ying: because LED and its application products industry chain length, different product characteristics, different levels, form, classification, structure of the standard, involving many departments, the standardization work of the main dispersion, so the standard formulation should fully consider the overall situation of the industrial chain, but also consider the coordination between departments, between upstream and downstream.

Over the past one or two years, the development of standards has become a hot spot in the LED industry, standardization work has been diversified, in the situation of "letting a hundred flowers bloom", it also brings some drawbacks, which are prone to contradictions, conflicts and duplication. Therefore, we also hope to communicate with the relevant departments, so that the development of more scientific and perfect standards. All departments and standardization organizations should have a clear division of labor and coordination, in the manufacturing, application, monitoring, certification, each has its own emphasis.

Reporter: in addition to the 9 standards have been submitted for approval, the working group is currently doing what work? What criteria will also be submitted for approval in the future?

Zhao Ying: we are currently concerned about