As LEDs are rapidly capturing the solid state lighting market, royal blue (~ 450 nm) laser pumped phosphor based white light sources have attracted serious attention from industry and academia in recent times. When we talk about laser based white light sources, one question we frequently encounter is “Why not a supercontinuum source?”. Unfortunately, the state-of-the art supercontinuum sources operating at the visible (VIS) wavelength region cannot match the strict demand for high luminous efficacy (lm/W) available from standard cold fluorescent lamps (CFL) or LED sources used in general purpose lighting systems. However Supercontinuum sources have found very useful applications in spectroscopy, metrology, ultra-WDM communication systems etc.
Dr. Chandrajit Basu, along with Mr. Gerolf Kloppenburg (IPeG), Mr. Shailesh Mishra and Mr. Axel Günther, performed an interesting colorimetric characterization of a commercial supercontinuum source (WhiteLase™ SC-400 from Fianium) on 16th August 2013. In order to verify its color rendering properties, the supercontinuum source was tested using an integrating sphere based spectrometer. A high CRI value of about 94 at a CCT of 4368K was obtained while the supercontinuum source was operated at full output power, Dr. Basu reported. “The CRI is indeed exceptional and this is the first-of-its-kind experiment with such a source, to the best my knowledge”, he added. The truncated (limited to the visible wavelength range provided by the spectrometer) spectrum obtained from the aforementioned supercontinuum source at full output power (average 4 W; repetition rate 40 MHz) is shown above.
