采用质心波长表征GaN基白光LED阵列的平均结温

结温是影响LED性能的重要参数,快速、准确地测量LED结温对LED产品设计、性能检测具有重要的意义。在不同驱动电流下,测量了GaN基白光LED阵列不同衬底温度时的归一化光谱分布,计算其质心波长,分析了质心波长随LED阵列平均结温变化关系,测量了LED阵列结温,并与中心波长法的测量结果进行对比。研究结果表明:经光谱仪测量,质心波长与平均结温变化存在良好的线性关系,且随着驱动电流的改变,直线斜率呈指数关系变化。与中心波长法相比,本方法的测量准确度更高。因此,采用质心波长测量GaN基白光LED阵列结温是一种直观的非接触的有效方法。

Characterization of the Average Junction Temperature of GaN-Based White LED Arrays by Centriod Wavelength

The junction temperature is an important parameter that affects LED performance. It is of great significance to measure the junction temperature of LED quickly and accurately for the design and performance testing of LED products. Under different driving currents, the normalized spectral distribution of the GaN-based white-light LED arrays at different substrate temperatures was measured, and the centroid wavelength was calculated. The relationship between the centroid wavelength and the average temperature of the LED array was analyzed. The junction temperature of the array was measured and compared with that measured by the central wavelength method. The results show that there is a good linear relationship between the centroid wavelength and the average junction temperature, and the slope of the straight line changes exponentially with the change of the driving current. Compared with the central wavelength method, the accuracy of this method is higher. Therefore, using centroid wavelength to measure the junction temperature of the GaN-based white LED array is an intuitive, non-contact effective method.