Transmission properties for optical glass and color and interference filters are among the main optical properties.

Transmission is measured using a spectrophotometer which enables values such as internal transmission, color code and the color code index to be calculated.
Available for this is a dual beam photometer with a dual monochromator and integrated Ulbricht sphere in the spectral range 250 nm – 2500 nm, at ± 0.5 % accuracy in transmission and a spectral resolution of < 0.1 nm.
In the 400 nm – 700 nm spectral range, transmission accuracy is ± 0.3 %. Measurements can be made on cuboid and rod test specimens at thicknesses of up to 300 mm.

Depending on the application, SCHOTT strives to achieve the best possible transmission properties, within technical and economic constraints, for optical glass and glass and interference filters.