After Hours, NIST and Suppliers Discuss UV LED Measurement

While NBA basketball and NHL hockey games beckoned on the sports bar TV sets upstairs, UV LED suppliers and a team of researchers from the National Institute of Standards and Technology (NIST) were sequestered in a downstairs meeting room debating how to set standards for emerging UV LED light sources.

The special Monday evening session held during the Radtech 2014 event was organized by Dr. Robin Wright, corporate scientist at 3M, who recounted his difficulties comparing LED sources with a variety of instruments. “We found differences as great as 30% from one instrument to another – we are not saying they wrong, but they are different” said Wright.

The development of LED measurement standards in an industry built around broad spectra mercury lamps has become more important as solid state sources become more commonplace. “One challenge has been the constantly shifting technology” observes Jim Raymont, Director of Sales for EIT LLC, the leading supplier of UV radiometers. “The choice of available wavelengths along with a several order of magnitude increase in irradiance combined with a wide range of array designs and optics has made it ‘interesting’ for our designers to develop a standard measurement instrument.”

NIST engineer Yugin Zong outlined various ways their agency can partner with industry. This includes characterizing “standard” LEDs, performing instrument calibrations, and helping to establish standard test protocols.