SBIR-STTR Award

Block MEMS, LLC proposes the development of an ultra high sensitivity MEMS enhanced, tunable diode laser spectrometer. With the aid of micro-electromechanical (MEMS) components, this spectrometer should achieve a size of <1800 cm3 while exhibiting sensitivities greatly exceeding the current JCAD specification, but with very low false alarm rate. It should exhibit extremely favorable Receiver Operating Characteristic (ROC) curves compared to current IMS or SAW point detection devices. While primarily for chemical detection, the unit should also be capable of biological cueing/detection consistent with current spectral data. The unit could also be adapted to serve as a moderate range (from 10 to 50 meters) standoff detector at somewhat larger size, weight, and power The approach combines several variable frequency Quantum Cascade Lasers operating in the 2-14 µm infrared (IR) “fingerprint” region. The unit can also measure some Mie scatter parameters which would help detection of biological aerosols. The Block approach further seeks to optimize the cost/benefit parameter by first analyzing the optimal spectral discrimination regions which differentiate among toxic species and between toxic species and military or other interferents. Through more efficient use of the spectral discrimination information, we expect further increase in the Signal to Noise Ratio (SNR).

Keywords:
Laser Spectrometer, Mems, Tunable Laser, Fabry-Perot, Quantum Cascade Laser

The Joint Services is seeking a miniaturized, low cost sensor for detection and identification of CWAs and TICs. To meet this requirement Block MEMS has very successfully completed a Phase I effort to develop a widely tunable MEMS enhanced Quantum Cascade Laser (QCL) spectrometer called LaserChemTM. LaserChemTM will have sensitivity in the parts per trillion, be under 1800 cm3 in size, have very low false alarms (due to its use of absorption spectroscopy in the “fingerprint” 8-12ìm spectral region and its 0.5 wave number resolution), and should cost under $3,000. In Phase I Block achieved world-record levels (>30%) of QCL tuning.. This wide tunability will necessitate the use of only 2 laser chips resulting in a very low cost sensor. The Phase II effort will focus on the development of a second QCL chip to complete coverage of the 10-12ìm region as well as the development of a MEMS constructed Fabry-Perot device to tune the QCLs. The team will develop a bench prototype ready for lab and field testing. Due to its size, cost and specificity, LaserChemTM will have broad applicability to military and commercial applications/markets, including the JCAD program, homeland security, analytical instrumentation, process monitoring, safety and medical.

Keywords:
Quantum Cascade Lasers (Qcls), Chemical Detection, Point Detector, Widely Tunable Laser, Mems, Infrared Spectroscopy, Ir