MEMS Correlation Spectrometer for High Precision CO2 Measurements

The U.S. Global Climate Change Initiative (GCCI), overseen by the DOE, has the goal of significantly reducing greenhouse gas emissions over the next 10 years. However, the sources and sinks of carbon dioxide and other greenhouse gases are not well understood. Very high precision instruments to quantify the concentrations and fluctuations of carbon dioxide are essential to improve this understanding; yet, existing instruments can not meet the combined specifications for precision, ruggedness, and cost. In this project, a new type of high-precision optical sensor, combining traditional grating spectroscopy with a micro-electro-mechanical system mirror array, will provide significant improvement in detection sensitivity and precision for carbon dioxide. This sensor will be compact and rugged, and will be able to operate unattended for extended periods of time. In Phase I, the methodology will be demonstrated and parameters for the mirror array will be optimized. Two different spectral bands will be compared to ascertain the best region for operation, with respect to precision, cost, and reliability. Commercial Applications And Other Benefits as described by the Applicant: The low-cost, field-deployable instrument should find use by government agencies for the rapid and precise measurements of important gases (H2O, CO2, CH4, etc.), for improving the prediction, and for modeling atmospheric dynamics and climate change. The methodology also should be applicable to identification of chemical agents for homeland security applications. Commercial applications would include gas-leak sensing of pipelines, fire detectors for commercial and private aircraft, combustor feedback control sensors, and process control sensors for energy and chemical production industries.