Assessment of the Blue Light Hazard for Light Sources with Non-Uniform Luminance

Abstract

ABSTRACT IEC 62471:2006 provides a method for assessing the risk of blue-light retinal injury. We examined the effects of nonuniformity of the luminance and spectral distributions of two light sources on risk level. When measuring the risk level of blue light, it is often measured for the region of maximum luminance. The spectral luminous efficiency, used to derive luminance, and a “blue-light weighting function”, used to evaluate the risk of blue-light retinal injury, differ in their distribution. Depending on the spectral distribution and luminous intensity distribution of a light source, the region of maximum risk does not always correspond to the region of maximum luminance. In this study, a hyperspectral camera was used to determine the risk level based on two-dimensional spectral radiance profiles; this was then compared with the risk level measured at the point of maximum luminance, and was found to differ in some cases.