Sample loaded in the capillary is illuminated from bottom by a cold light source. Filters can be introduced in light path to allow sample illumination at various spectra. There is the current filter setting:

Position Wavelength Nick name
1 610-1800 nm red
2 325-385 nm UV
3 495-1800 nm yellow
4 315-445 nm, 715-1095 nm violet
5 275-375 nm UVlow
6 435-500 nm blue