The blue light hazard (BLH) to human eye’s retina is now a new issue emerging in applications of artificial
light sources. Especially for solid state lighting sources based on the blue chip-LED(GaN), the photons with
their energy more than 2.4 eV show photochemical effects on the retina significantly, raising damage both in
photoreceptors and retinal pigment epithelium.
The photobiological safety of artificial light sources emitting optical radiation has gained more and more
attention worldwide and addressed by international standards IEC 62471-2006(CIE S009/E: 2002).
Meanwhile, it is involved in IEC safety specifications of LED lighting products and covered by European
Directive 2006/25/EC on the minimum health and safety requirements regarding the exposure of the workers
to artificial optical radiation. In practical applications of the safety standards, the measuring methods of
optical radiation from LED products to eyes are important in establishment of executable methods in the
industry. In 2011, a new project to develop the international standard of IEC TR62471-4,that is “Measuring
methods of optical radiation related to photobiological safety”, was approved and are now under way. This
paper presents the concerned methods for the assessment of optical radiation hazards in the standards.
Furthermore, a retina radiance meter simulating eye’s optical geometry is also described, which is a
potential tool for blue light hazard assessment of retinal exposure to optical radiation. The spectroradiometric
method integrated with charge-coupled device(CCD) imaging system is introduced to provide more reliable