白光LED标准出炉随着LED研发技术的突飞猛进，已被许多人视为充满潜力的新世代主要照明光源，然而LED具有与传统照明光源截然不同的空间发光特性，使原本适用于传统光源光学特性测量的方式未必适用于LED,如光通量（LuminousFlux）、光强度（LuminousIntensity）及色度（Chromaticity）测量，否则LED的测量精度及准度都将成问题。因此，全球各大标准协会均修订或是新增LED测量标准，但由于LED封装种类繁多，性能也各不相同，所以也有协会针对不同用途的LED制定新的测量标准
The International Commission on Illumination (CommissionInternationaledelEclairage; CIE), for example, substantially revised in 2007 measured the existing technical documentation LED CIE-127, but a lot of controversy, there are still many problems to be resolved measurements, and by the U.S. Department of Energy (DOE) dominated, and its solid-state lighting products with the promotion process, by the American National Standards Institute (ANSI) Illuminating Engineering Society of North America (IESNA) standards group formed, being solid-state lighting standards related to the formulation of the test, including the amount of optical activity measurement, color measurement, and life assessment measures and other standards, but these standard features in its content of solid-state lighting will be evaluated as a whole, that is, LED monomer can not by the norms of these standards for measurement.
In recent years, China also committed to promoting standards of semiconductor devices, the government's support, has launched a testing method of semiconductor light emitting devices, and other relevant standards are being considered.
However, white LED lighting standards in the promotion, the most advanced countries are Japan, which Japan Illuminating Engineering Society (JIES), Japan's Commission on Illumination (JCIE), Lighting Industry of Japan (JIL) and the power ball Industries Association of Japan (JEL ) in 2004, four groups have been set a common standard "method of lighting with white LED metering General", as the only white LED for lighting measurement standard set, when its first edition has not been the lead in formulating a number of norms off projects, such as the manufacture of standard LED, small light intensity measurement modules and life assessment methods.
LED light of progress of measurement standards for content and there is still room for expansion, four groups published in the March 2006 revision of this standard to increase the standards and revise the original content, chromaticity and luminous flux measurement measurement methods to make more detailed specifications. However, based on a cautious attitude, there are still many parts are placed in the subsidiary part of some, but not the actual standard, but the instructions in the relevant specifications are still very detailed, can be found at this stage of the LED standard international literature, this standard can be said that the contents of the most complete specifications. In the current industry is still a common lack of adequate case LED measurement specifications, the standard will be a very important reference. The following highlights key provisions of this standard, as well as the additional part of the revision.
Limit the application of white LED lighting at the beginning of the standard title, and already declared is limited to lighting for white LED, it is limited to that goal will be measured using white light LED, to limit the LED compared with the standard method of measurement effectively enhance the accuracy and content of the standard LED to make a very detailed provisions. In the light intensity measuring part, the International Commission on Illumination in accordance with standard conditions under the measure; part in the flux measurements, it will be using the integrating sphere (IntegratingSphere) measurements, and an increase in the revised version of the color, correlated color temperature (CorrelatedColorTemperature; CCT), color rendering index (ColorRenderingIndex; CRI) and other measurement methods, and in principle the use of an integrating sphere as its school system, the incident light.
This standard is mainly developed specifications for the single LED, but the LED modules for a small measure of light intensity is also included specifications for a small LED modules, its not necessarily apply under the CIE standard conditions, the average LED light intensity measurement method.
White LED lighting standards and defined the standards of other LED's the biggest difference in the "white lighting LED" make a very clear definition. According to the interpretation of this standard, the so-called "white lighting LED" The measurement of the average light intensity of luminous flux or light color, should meet the spectrum (Spectrum), covering almost the full range of visible light region, and which can not have missing parts; correlated color temperature of range (2500 ~ 10000) K or less; and the correlated color temperature in the CIE1960 uniform color (UniformChromaticityScale; UCS) coordinates, with the Planck trajectory (PlanckianLocus) of the deviation (Duv) three conditions must be less than 0.02.
It should be noted that in this definition, RGB tri-color LED lighting will be excluded from the scope of white LED, in fact, the interpretation of the annex to this standard, the white LED lighting is a controversial definition of the project , the provisions of the correlated color temperature, due here for the general lighting, so the start is the same level with the fluorescent light (correlated color temperature for the (2700 ~ 8000) K or so) to consider, however, its reference to the actual development of the current white light LED technology, it will set correlated color temperature range from (2500 ~ 10000) K range.
Light intensity / luminous flux measured in two ways because there is no large number of standardized and unified LED package shape, size and lighting features, but have different purposes in accordance with the design of various structures, it is difficult to measure LED. Therefore, standard LED should have the structure, performance, reproducibility must be provided for.
In this standard, a standard LED light intensity is divided into two kinds of measurements and flux measurements, based on measured characteristics of its different for different design concepts. For example, a standard measurement of light intensity LED, the light intensity measurement as methods, the tested LED mechanical axis (MechanicalAxis) aligned metering device (PhotoDetector) is a correction factor is important, so the standard mechanical axis alignment is easy with bullet-type (Lamp) package as a standard form; The flux measurement standard LED, taking into consideration the provisions of all flux measurements, the use prevents the rear towards the LED emit light, and more uniform light intensity metal pot (TO-Can) package as a standard form. It is worth noting here two forms of the standard LED, are using indium gallium nitride (InGaN) chip series with yttrium aluminum garnet (YAG) phosphor made of white LED, the corresponding item in the definition white LED for lighting described in part without the lack of wavelength.
Since the standard LED is an important reference measurement, so the standard hope to minimize the influence of the surrounding environment, the optical and electrical properties of the instability to a minimum, to achieve the desired reproducibility requirements. In addition to the standard measurement of the ambient temperature changes limit must be less than 2 ℃, for the reduction of the initial LED changes, the proposal should have been more than 100 hours use of constant current (eg 20 mA) drive standard LED, standard LED of the ambient temperature shall be control in 25 ℃. In the revised edition, the increase in temperature in Annex 4 slot (Socket) (as a function of chip temperature control lighting fixture) stated their requirements in the case of constant current, LED time to reach thermal equilibrium (I hope at least 5 minutes) after the lighting measurements.
