Standardization of a UV LED Peak Wavelength, Emission Spectrum, and Irradiance Measurement and Comparison Protocol.

Abstract

Standard protocols for the measurement of irradiance, peak wavelength, and emission spectra have not yet been established for UV LED devices. This lack of standardization creates an uneven field for comparison between products. A detailed protocol was developed and tested in 14 facilities spanning manufacturers of UV LEDs and devices and research institutions in seven different countries. This protocol includes equipment calibration specifications, methods for the measurement and comparison calculations of irradiance and emission spectra, methods for the determination of peak wavelength, quality control and quality assurance steps, and industry-wide tolerances to error for each type of measurement. Measurements of the same source by operators using different equipment resulted in 2-10× the error found when measurement equipment provided as part of the study was used by each participant. The data were used to identify outliers, determine prediction intervals, and define acceptable tolerances to error. With this protocol, manufacturers have a means to report their UV LED specifications with verifiable quality control and quality assurance steps. The protocol and data generated from this study will create more confidence in the industry and standardize the comparison of UV LEDs by consumers, researchers, designers, and regulators.