A tungsten halogen lamp is the most common light source used in spectrophotometers. It consists of a tungsten filament enclosed in a glass bulb and a halogen portion included to recover the evaporated tungsten. It provides a usable wavelength range from 330 to 1100 nm in the visible to near-infrared region and has a lifetime of about 3000 hours.
A deuterium lamp is a discharge light source with gaseous deuterium sealed in a bulb. A deuterium lamp covers the ultraviolet region from 190 to 450 nm with a smooth light intensity distribution and has a lifetime of about 1000 hours. The above two lamps are often combined to cover a full range of UV and Vis light.
A xenon lamp is a discharge light source with xenon gas sealed in a quartz glass bulb. It produces a continuous spectrum from the ultraviolet to the near-infrared, ranging from 190 to 1100 nm. Xenon flash lamps generate light by pulsed ignition, which is integrated over a defined time span to achieve a complete spectrum scan, they require no warm-up time. The pulsed light generation produces little heat and the lifetime is long, lasting up to 5,500 hours and corresponds to 50 Hz flashes at constant operation. The usage of xenon lamps means less needed maintenance and a longer lamp lifetime. FastTrack Technology by METTLER TOLEDO consists of a xenon flash lamp, quartz glass fibers and an array setup.