国际照明委员会的CIE127号文件专门针对发光二极管(LED)的光辐射测量方法给出了A、B 两个测量“LED平均发光强度”的条件,并得到世界同行的普遍认可.然而,实验测量中发现同一只LED 管在不同的测量条件下的平均发光强度相差悬殊,甚至有LED 管在A、B 两个不同条件下的平均发光强度测量值相差近10%,严重影响了LED 光度量值的准确评价.对LED 光强空间分布数学建模的分析,通过计算以及实验验证表明将测量角定为0.5°,测量距离变为645 mm,能够将LED 光强空间分布不均匀对LED 平均发光强度测量的距离影响减小到0.5%以下,从而保证LED 平均发光强度量值的一致性.

Commission International de Illumination (CIE) publishes‘CIE 127 technical report’(CIE 127) for light emitting diode(LED) measurement.Two different conditions (condition A and condition B) for measurement of averaged LED Intensityare proposed in CIE 127,and the LED measurement method gradually win the worldwide recognition.Most of the LED has a different averaged LED intensity in these two measurement conditions,and the difference is up to 10% in some LED measurements,so it is difficult to evaluate the averaged LED intensity accurately.Mathematical models for different kinds of luminous intensity distribution have been created according to a large amount of measurement data.Simulation results and measurement results make clear that the impact of strong directional luminous intensity distribution can be reduced to less than 0.5% when distance between detector and LED is up to 645 mm,and the equivalent full plane angle is approximately 0.5°,this work makes the value of averaged LED intensity have consistency widely.