UV LED Benefits: Wavelength Selection

Technology > UV LED Benefits > Wavelength Selection

Enables the ability to select narrow band output wavelength to match peak absorption spectra of a target organism



UV-C LEDs are monochromatic and available in multiple wavelengths. This affords targeted performance for specific waterborne pathogens.




With the popularity of low-pressure mercury lamps, 254 nm has been thought of as the ideal wavelength, even though the peak germicidal effectiveness falls between 260 and 270 nm, depending on the specific pathogen. UV-C LEDs are quasi-monochromatic (majority of output falls within a 10-nm gap) but can be engineered in a variety of wavelengths within the germicidal range to target specific pathogens or the general peak pathogen UV sensitivity. (e.g., 255, 265, 275 nm, etc.). The choice of wavelength is usually dependent upon multiple factors which may include:


  • UV-C LED Cost - Although rapid advances in UV-C LED manufacturing and increasing volumes are steadily driving down prices, the manufacturing cost of UV-C LED devices varies by wavelength.

  • UV-C LED Lifetime - Current best-in-class devices have a lifetime of 10,000 hours with 70% of initial output (L70), however, there is a high degree of variability between LED device manufacturers specifications related to lifetime at different wavelength values.

  • UV Optical Output - Output power of a UV-C LED device varies based on wavelength. Current best-in-class devices deliver optical output values up to 100 mW.

  • Target Organism Action Spectra - Pathogens have different spectral sensitivity for different UV wavelengths.

  • UV Transmittance - The UV transmittance of the fluid being treated is a critical parameter for sizing UV systems. Different water UV-Transmittance values have different absorbance characteristics that must be accounted for.


The most effective solution often lies at the intersection of many of the above factors and the most effective germicidal wavelength is not always the correction application wavelength. Our extensive knowledge of disinfection products and applications allows AquiSense to provide the most optimal solution for balancing all of these factors.

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UV absorption Effectiveness chart

Disinfection effect is dependent on UV wavelength

Wavelength sensitivity varies by microbe

Source: S. Beck, et al. Water Research 70 (2015) 27/37



The ability to select a specific output wavelength of an LED enables closer matching to peak absorption spectra of a target organism.




Many laboratories and researchers are currently conducting bench scale inactivation research using multiple UV-C wavelengths. This research is expected to support the further implementation of selectable wavelength products in the future.


The AquiSense PearlLab Beam™ is a compact Collimated Beam Device which employs UV LEDs and is available in a suite of individually addressable wavelengths. More information can be found here.

PearlLab Beam™ - UV LED Collimating Beam Device