Paper VT-MoA4
Commercial Applications and Benefits of Continuous-Wave Cavity Ring-Down Spectroscopy

Monday, October 31, 2011, 3:00 pm, Room 111

Continuous-Wave Cavity Ring-Down Spectroscopy (CW-CRDS) is a laser-based state-of-the-art detection technique. Based on first principles, it directly derives the absolute optical loss due to absorption inside the cavity from a simple time measurement, independent of laser intensity noise and optical detector drift.

This highly sensitive absolute absorption measurement technique was first commercialized by Tiger Optics for sub parts-per-billion (ppb) level detection of moisture in inert gases. More than a dozen national metrology labs now use this technique as their moisture transfer standard. Several of these key national labs recently concluded a multi-year project comparing the performance of their different moisture standard generators by using two Tiger Optics CW-CRDS devices as their “referees”, shipping them around the globe across three different continents. Inter-comparison data from this comprehensive study will be presented.

With over 1000 measurement points worldwide, CW-CRDS has gained widespread acceptance and growing use in a series of challenging, real-world industrial applications, well beyond trace moisture in simple matrices. We will demonstrate the strong capability of CW-CRDS for a diverse group of analytes over a large dynamic range and under widely varying application conditions. In addition, starting with ultra-high-purity, sub or low parts-per-billion measurement, this technology is now increasingly sought for higher parts-per-million applications as well. Taking maximum advantage of its exceptional dynamic range, with a variety of flexible configurations, CW-CRDS-based instruments address these various applications with a self-verifying measurement solution that is fast and sensitive, yet extremely robust and simple to operate.