AN OPTIMIZATION OF RETINAL THERMAL HAZARD MEASUREMENT FOR RETINAL THERMAL HAZ

摘要

The photobiological safety of lamps and lamp systems has been paid close attention to in recent years [1, 2]. According to standard CIE S009/IEC 62471-2006, the hazard wavelength range covers from 200 nm - 3 000 nm, in which 3 types of hazard are spectral selective: Actinic UV Hazard (200 nm - 400 nm), Retinal Blue-light Hazard (300 nm - 700 nm, RBH for shorten), Retinal Thermal Hazard (380nm-1400 nm, RTH for shorten). Theoretically, the spectral power distribution from 200 nm - 1 400 nm should be measured for a complete test of the photobiological safety. Such a wide band covers 3 spectral orders, it is not only costly, but also hard to achieve high accuracy. By research, we find that for most real light sources, especially for generally lighting sources (GLS), the spectral measurement in infrared part (780 nm - 1400 nm) for RTH evaluztion is unnecessary for the Risk Group (RG) classification. Because the lamps or lamp systems are classified as the highest RG that any hazard could reach, and the other related hazards e.g. the RBH or the Infrared Radiation Hazard for the eye (780 nm - 3 000 nm, Eye's IR for shorten) can usually has higher RG than the RTH, namely "cover". Hence the cost of photobiological safety calssification for light sources can be greatly saved. And this research also gives guidance to optical design to avoide RTH.