Due to the high light transmissions of most types of glass it is necessary to determine the optic permeability in a huge number of individual cases. For the different wave lengths of the spectrum appropriate methods and apparatus are on hand.
Various derived parameter (chromaticity point, concentration of specific components, characteristics concerning light protection) can be gained with the measureable spectral data.
In this procedure two-sided polished and plane parallel sheets are utilized.
(Samples: plane parallel sheet, polished on both sides, 30×20 mm, thickness: 1-10 mm, tube section is possible)