UV and blue-violet light
(1) Blue-violet light is between 400 and 455nm as stated by ISO TR 20772:2018.
(2)McCarty CA, Taylor HR. A review of the epidemiologic evidence linking ultraviolet radiation and cataracts. Dev Ophthalmol. 2002; 35:21-31. Sunlight and the 10-year incidence of age-related maculopathy: The Beaver Dam Eye Study. Arch. Ophthalmol., 122, 750-757. New discoveries and therapies in retinal phototoxicity, Serge Picaud et Emilie Arnault, Points de Vue N°68, Spring 2013.
(3)In vitro photobiology experiments conducted by Essilor and Paris Vision Institute. Primary retinal pigment epithelium cells were photosensitised with A2E, a major component of the age pigment lipofuscin. These cells were then exposed for 18 hours to 10 nm illumination bands centered from 390 to 520 nm in 10 nm increments (+ illumination band centered at 630 nm). To mimic physiological light conditions, light irradiances were moderate and normalised with respect to the natural sunlight reaching the retina. (Arnault et al., 2013 PLOs One).
(4)Blue-Violet light photo-protective potency is measured or calculated. Measurements are done through in vitro photobiology experiments conducted by Essilor and a 3rd party. Photosensitized RPE (Retinal Pigment Epithelium) cells are exposed to Blue-Violet light, reproducing the physiological exposure to sunlight of the 40 year old eye. Calculation model is using an interpolation method of spectral data between 400 and 455nm. This model has been designed thanks to correlation between spectral measurements and in vitro test results on outer retina cells, with a dispersion of 5%. For Eye Protect System™ lenses with Crizal Forte® UV coating, 25% (+/-5%) decrease in light-induced retinal cell death versus no filter. For standard lenses: 1.5 or Poly material with Crizal Forte® UV coating, about 7% decrease.