title: Photochromic dynamics of ophthalmic lenses.
abstract: We describe and characterize a straightforward test setup for characterizing temporal and spectral dynamics of photochromic spectacle materials. Three measurement examples of contemporary silicate and organic photochromic spectacles are provided. The setup showed a good absolute accuracy of ≤5% of the luminous transmittance (τ(v)) and repeatability of better than 3%. The samples showed different fading times. The sample with the highest dynamic range was the slowest and showed a noticeable change in the transmission spectra during deactivation. The silicate had the lowest dynamic range but also the most homogeneous transmission spectra throughout activation and deactivation. The proposed test device provided accurate results for spectral and temporal dynamics of photochromic materials under realistic conditions.
authors.affiliation: Experimental Ophthalmology, Saarland University, Kirrberger Strasse 100, 66424 Homburg/Saar, Germany. timo.eppig@mx.uni‐saarland.de
authors.forename: Timo
authors.initials: T
authors.lastname: Eppig
authors.forename: Alexis
authors.initials: A
authors.lastname: Speck
authors.forename: Melanie
authors.initials: M
authors.lastname: Gillner
authors.forename: Dieter
authors.initials: D
authors.lastname: Nagengast
authors.forename: Achim
authors.initials: A
authors.lastname: Langenbucher
mesh_terms: D005135:Eye Protective Devices / Q000145:classification* / Q000592:standards*; D005139:Eyeglasses / Q000145:classification* / Q000592:standards*; D011108:Polymers / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D013053:Spectrophotometry; D014466:Ultraviolet Rays
chemical_list: D011108:Polymers; D017640:Silicates