Fluorescent Light Sources

Fluorescent light sources used in spectroscopy and microscopy include light-emitting diodes (LEDs) and laser diodes, mercury or xenon arc-lamps, and halogen lamps. Each light source differs in the way wavelengths of light are delivered. Halogen lamps deliver continuous wavelengths of light in the near-ultraviolet to some parts of the infrared wavelengths, while mercury or xenon arc-lamps deliver continuous light in the UV and visible light ranges. While LEDs only deliver light in narrow wavelength ranges, these lights can be combined to provide a wide spectrum from the ultraviolet to the infrared range. When choosing a fluorescent light source, it is important to consider the wavelengths required, its compatibility with your instrument, and the cost—while LEDs have higher upfront cost, their lifetime cost is often lower than other light sources.