【摘要】 根据发光二极管(LED)的封装分析发光芯片的虚像位置,推导出利用光照度平方反比定律测量LED平均光强时被照面与光源实际距离的校正值。测试了不同发散角LED在不同测试距离下的光照度,发散角越小,光照度偏离距离平方反比定律的误差越大。通过数据拟合校正测试距离,与理论分析、仿真结果相吻合,校正后LED的平均发光强度、照度与测试距离符合平方反比定律。结果进一步说明了LED发光强度测量标准中两种距离的设定有待商榷。该实验对光学工程类学科的照度平方反比定律验证实验设计与延伸有一定启发作用。更多还原

【Abstract】 Based on the package of LED,this paper analyzed the virtual image position of the LED chip and deduced the correction value of the actual distance between the illuminated surface and the light source when the average light intensity of LED was measured by using the inverse square law of illumination. The illuminance of LED with different diverging angles at different measuring distances was tested. The smaller the divergence angle was,the more it deviated from the inverse square law. Through data fitting,the measuring distance was consistent with theoretical analysis and simulation results. After calibration,the average luminous intensity and illuminance of LED were in line with the inverse square law. The results further illustrated that the setting of two kinds of distance in the LED measurement standard still need to be discussed. This experiment has some enlightening effect on the design and extension of inverse square law of illuminance experiment in optical engineering discipline更多还原