UV light measurement - Meet the challenge

Ultraviolet (UV) radiation is an invisible form of electromagnetic radiation with a very short wavelength between 200 nm and 400 nm. The relevant UV spectral range is normally subdivided into three bands: UVA (315-400 nm), UVB (280-315 nm) and UVC (200-280 nm). Based on its characteristics, e.g. germicidal effect and photolysis, UV radiation is widely used for air & water purification, industrial & cosmetic curing, surface inspections as well as indoor gardening.   

Over the past decade UV LEDs emerge as highly attractive alternative to conventional UV sources. They are cost effective and energy efficient devices in a small housing. These advantages allow new fields of applications and access to a larger group of users – even in the consumer market, e.g. water purification.

The development of UV LEDs and their production are very challenging. Particularly the UV-B and UV-C spectral ranges are very demanding. This challenge becomes apparent with the decreasing optical output power with decreasing emission wavelength. Therefore, the requirements for the corresponding optical measurement equipment with respect to sensitivity and accuracy are very high.

Instrument Systems offers complete solutions for high quality and high performance measurements of UV-A, -B and -C radiation starting from 200 nm. They comprise

  • the well-proven Instrument Systems spectroradiometers,
  • integrating spheres made from PTFE for high UV throughput,
  • auxiliary lamps for self absorption correction
  • and further measurement adapters and accessories.

These measurement solutions and their components are designed for high sensitivity measurements, high accuracy and high stability measurements in the UV spectral range for laboratory and production applications.

In addition to these hardware components Instrument Systems offers advanced know-how and methodology to further push measurement performance. All UV measurement systems are delivered with a PTB traceable calibration and an optional state-of-the-art stray light correction, which give our customers additional value with respect to high accuracy in the UV spectral range.

Our measurement solutions for UV LEDs include a variety of equipment and accessories:

Icon Pfeil  PTFE Integrating spheres for determining UV radiantlux

Icon Pfeil  Spectroradiometers  with PTB traceable calibration

Icon Pfeil  State-of-the-art stray light correction for efficient stray light suppression

Icon Pfeil  Test sockets for fast insertion and rapid changing of LEDs

Icon Pfeil  Auxiliary light source for self-absorption correction

Icon Pfeil  Laboratory software suite as well as Command library optimized for production applications

UV measurement - The importance of stray light correction

The impact of stray light correction on the spectrum of a calibration source is particularly distinct in the UV and IR spectral range, because the detector of an array spectroradiometer has only a low sensitivity at the edges. Due to the division of the measured spectrum by the reference spectrum, errors due to stray light contaminated measurement spectra are intensified in the areas of lower sensitivity. Thus, stray light correction leads directly to a higher precision in radiometric evaluations of UV LEDs.