Table 1

Integrated power of light sources and time (in minutes) to reach the ICNIRP threshold guidelines for blue light photochemical retinal hazard. Sources of various brands (brand 1–4) were measured with filters that were provided by the manufacturer (filter A–E) or without filter (no filter). Maximal exposure time was calculated for a 10 mm distance between retina and light source, a 300 μm fibre diameter and a 20° acceptance angle. In addition, we evaluated the effect of adding three different long pass filters

Light sourceIntegrated power (mW)Calculated threshold exposure time (minutes)
without filterswith GG475with OG450with OG435
Metal halide, brand 1, no filter40.80.21.70.50.3
Metal halide, brand 1, filter A29.40.52.00.80.6
Metal halide, brand 1, filter B43.40.21.40.50.3
Metal halide, brand 2, no filter38.50.41.90.80.5
Metal halide, brand 2, filter C24.40.82.71.10.9
Halogen, brand 3, no filter8.42.113.25.64.0
Halogen, brand 4, no filter22.40.84.01.71.2
Xenon, brand 2, filter C46.20.41.20.50.4
Xenon, brand 2, filter D35.90.11.60.50.3
Xenon, brand 2, filter E64.10.11.10.40.3