光子学报, 2013, 42 (12): 1496, 网络出版: 2013-12-16
基于成像方法LED有效辐亮度测量系统设计
Design of a Weighted Radiance of the LED Measuring System
光化学 光生物安全 有效辐亮度 模拟人眼成像亮度计 视场 Photochemistry Photobiological safety Weighted radiance Radiance meter Field of view
摘要
从有效辐亮度出发,采用模拟人眼成像的电荷耦合元件成像仪和光谱仪相结合的方式,建立了发光二极管有效辐亮度测量系统.参照光生物安全标准中的测试要求,从理论上分析了传统亮度计在进行光生物安全测试时的不足,采用传统的亮度计和本文设计的模拟人眼成像的亮度计结合光谱仪系统测试两种典型发光二极管.测试时先进行模拟人眼成像,再结合光谱仪对有效辐亮度进行测量,最后两种亮度计的测试结果进行了分析.结果表明:采用传统亮度计测量白光发光二极管有效辐亮度值为81.8 W/m2·sr,平均强度为23.3 cd,蓝光发光二极管的平均强度仅为2.42 cd, 蓝光发光二极管有效辐亮度值为262 W/m2·sr;而采用成像仪和光谱仪结合的系统测得的白光发光二极管有效辐亮度为137.0 W/m2·sr.显然,白光发光二极管的有效辐亮度比蓝光发光二极管的有效辐亮度值小,采用传统的亮度计用于光生物安全测试会低估被测发光二极管的光生物危害性,采用新设计系统则会更加精确地测出发光二极管的有效辐亮度值,满足发光二极管的辐射安全测量要求.
Abstract
The weighted radiance of LED is one of the most important parameter in photobiological safety evaluation of LED, so a special measurement system was established which combined of a CCD camera simulated of the human eye imaging and a spectrometer. Reference the testing requirements in the standards, the deficiencies of the traditional luminance meter were analyzed theoretically and two typical LEDs were measured by the traditional luminance meter and the retina radiance meter. There were great differences between the weighted radiance in photobiological safety evaluation and the radiance in traditional optical measurements, and the special requirements made the traditional luminance meter cannot be able to measure the weighted radiance. Finally, the differences between the two luminance meters were introduced and test results were analyzed using the two luminance meters. The experimental results show that the weighted radiance of the white LED tested by the traditional luminance meter is 81.8 W/m2·sr, but the value is 137.0 W/m2·sr when the LED is tested by the novel system. Obviously, traditional luminance meter is not suitable for measuring the effective radiance and it will underestimate the hazard.
罗勇军, 牟同升. 基于成像方法LED有效辐亮度测量系统设计[J]. 光子学报, 2013, 42(12): 1496. LUO Yongjun, MOU Tongsheng. Design of a Weighted Radiance of the LED Measuring System[J]. ACTA PHOTONICA SINICA, 2013, 42(12): 1496.