In 1986, 20 years after the first photochromic mineral lens, Rodenstock launched the first generation of photochromic plastic lenses, Perfalit ColorMatic. Dr Herbert Zinner, Dr Herbert Schuster, Dr Udo Weigand and Dr Werner M
A colourless organic molecule is excited by UVA irradiation (Figure 1). As a result, a certain chemical bond of the molecule is broken and the accompanying structural and electronic change shifts the absorption spectrum into the visible region - the molecule is now coloured ('activated'). The molecule relaxes back to the colourless ('inactivated') state predominantly by thermal rearrangement ('fading').
Register now to continue reading
Thank you for visiting Optician Online. Register now to access up to 10 news and opinion articles a month.
Register
Already have an account? Sign in here