Thursday, February 28, 2013
New Lens from Essilor Controls Emission of Blue Light
Essilor has launched what it calls the first lenses offering selective protection against harmful blue light -one of the risk factors in retinal cell degeneration- and against UV rays.This major innovation was made possible thanks to an ambitious four-year research program conducted in partnership with Paris Vision Institute, according to Essilor. After two years, the joint venture team identified, with a high level of accuracy, that portion of the visible light spectrum that is noxious to retinal cells. Emitted by the sun and also by artificial light sources such as LEDs and computers or smartphones, blue light (between 380-500 nm) plays a beneficial role on health, such as regulating biological clocks. However, a specific band of this light might have a harmful effect on the eyes. In order to identify the part of the spectrum that damages the retina, the researchers developed an in vitro test on retinal cells with narrow screening light exposure to determine the harmfulness of rays depending on their wavelength. This test--a first in ophthalmic optics--allowed for the discovery that wavelengths between 415 and 455 nm (spectral band centered at 435 nm +/- 20nm) are the most harmful for the target retinal cells.After two years of research, the company has developed the Crizal Prevencia lens, which is able to protect the eye from wavelengths that contributes to the degeneration of retinal cells while allowing beneficial blue light to pass through. This is a new category of preventive lenses developed using Light Scan, an exclusive technology which filters light selectively- by letting beneficial blue light pass through. Read more.