Smiths Detection and Block MEMS to Develop Chemical Detection Tech

Threat detection and security technology company Smiths Detection will work with Block MEMS to develop a proximate chemical agent detector (PCAD) for noncontact detection of solid and liquid threats on various surfaces. The Defense Threat Reduction Agency and the Joint Program Executive Office for Chemical Biological Radiological Nuclear Defense Hazards selected Smiths for the project. Specified hazards include chemical warfare agents, toxic industrial chemicals, nontraditional agents, opioids, and explosives.

Block MEMS’ quantum cascade lasers (QCLs) will be the core technology in the system. Block, and its affiliate Block Engineering, are suppliers of QCL-based products that support integration into applications including trace-level standoff detection of explosives and narcotics, as well as the detection of toxic gases. Block has developed the lasers in the last decade with over $30 million in funding from the U.S. government.

According to its website, Block QCL systems offer continuous tuning up to 1050 cm^-1. Each laser pulse is monitored by built-in electronics, which perform analyses after the pulse interaction with the substances under investigation. Algorithms convert the measurements into infrared spectra to be analyzed by built-in libraries that also account for background interferences and provide identification of the substance. The QCLs operate in the 200-kHz range and all data processing is performed in real time, enabling subsecond measurements.

This process — pre-dispersive spectroscopy — involves splitting light into the various wavelengths before its interaction with the target substance, the company said. Such operation offers very narrow spectral linewidths, which enable high-resolution spectral measurements, especially for gases or substances that have spectral features too close to each other.

Smiths Detection previously developed chemical detection technology for the U.S. Department of Defense and recently secured a contract to develop an aerosol and vapor chemical agent detector. The PCAD program, with a total contract value over $38 million, involves five phases of R&D over seven years and will be conducted between Smiths Detection’s U.S. headquarters in Edgewood, Md., and Block headquarters in Southborough, Mass.