Fully Integrated Low-Cost High-Precision Carbon Dioxide Analyzer

Understanding global warming requires continuous field measurements of carbon dioxide concentrations. High-precision measurements of a part-in-3000, or better, are required. However, these high-performance instruments must meet stringent cost objectives. A simple, rugged, infrared spectrometer can provide the required measurement precision at the solicited volume price point. Vista Photonics proposes to develop a laser diode based spectrometer that can determine carbon dioxide concentration to 0.1 ppm precision in less than one minute with a retail price at $5,000. A bench top laser diode (LD) wavelength modulation spectrometer (WMS) will be constructed for Phase I proof-of-principle. The sensitivity and selectivity of the LD-WMS instrument for carbon dioxide will be determined using infrared laser diodes. The low-cost sensor version will measure dry or wet ambient air with no sample preparation. The requirements for calibration and measurement procedures will be determined for long-term field deployment. Commercial Applications and Other Benefits: The proposed technology offers high-performance in an inexpensive, field-compatible, package. The spectrometer can meet DoEs low solicited price point, which sets it apart from existing devices of comparable performance. The approach will offer a compelling blend of price, performance and physical advantages in a variety of gas detection applications. Examples include atmospheric monitoring, environmental regulatory compliance, process gas analysis, and biomedical breath diagnostics.