Avantes Deuterium light sources are known for their stable output ad are used for UV absorption or reflection measurements. These can also be used as irradiance calibration sources due to their high stability. The standard AvaLight-DH-S mixes the halogen light with the Deuterium light, thus producing a wide spectral range light source. The output spectrum of Deuterium light sources exhibits several peaks, with a prominent peak at 656 nm. The AvaLight-DH-S-BAL incorporates a dichroic beam splitter installed to minimize these peaks, providing a smooth spectrum from 200-2500 nm.