FY2010 - Oak Ridge National Laboratory

Director’s R&D Fund—
National Security Science and Technology
covering distances up to 100 m using eye-safe QCL. RePAS also provides a path towards developing a
broad area imaging system for chemical imaging of surfaces. We will develop a system that images
surface contamination of a large area within seconds.
Mission Relevance
Currently, there is a strong interest expressed by defense and national security agencies for developing
standoff detection and standoff chemical imaging techniques with high sensitivity and selectivity.
Standoff detection of chemical signatures is critical, and its applications range from obtaining precise
chemical composition of CB warfare agents to determining the signatures associated with improvised
nuclear devices (INDs). Another application will be for the verification of decontamination of weapons,
buildings, vehicles, airplanes, and equipment after exposure from an attack. Obtaining chemical
signatures of CB agents with extremely high selectivity and sensitivity using a man portable device is
critical in many areas such as homeland security, military, national defense, and monitoring the
clandestine production of weapons of mass destruction. Proposals on selective and sensitive detection of
explosives, chemicals, and agents are entertained by many agencies such as the Department of Homeland
Security (DHS), the Air Force Research Laboratory (AFRL), the Defense Threat Reduction Agency
(DTRA), the Defense Advanced Research Projects Agency (DARPA), and the Office of Naval Research
(ONR). Many private companies are also interested in licensing the device once proof-of-concept is
demonstrated. The RePAS technique can find applications that range from water and food quality
monitoring to environmental remediation and medical diagnostics. The present project aims to develop a
device with a broad IR range for increasing selectivity. A wider wavelength range for RePAS will help to
apply this method in early cancer diagnosis. For example, the probing end of the RePAS can be
incorporated into tools for colonoscopy and biopsy. The National Cancer Institute (NCI) of the National
Institutes of Health (NIH) is very interested in imaging applications for cancer detection, detection of
margins in surgical removal cancer tumors, and imaging flat lesions related to colon cancer.
Results and Accomplishments
After procuring necessary materials, planning experiments, and designing apparatus, the proposed
investigations, based on experiments, began to produce preliminary results. A number of interesting
observations have been made that have provided optimism in the RePAS technology. We have observed
IR absorption-induced changes in temperature on target surfaces in a standoff fashion; however, this
fascinating effect needs further investigation. Furthermore, some strong evidence of QCL light-induced
changes in explosive residues using an IR camera warrant more study. We have investigated the effects of
illumination angle on IR-absorption and the effects of laser power, both important parameters that must
be taken into account in the field. Another important undertaking was the initial characterization of the
background spectra of different surfaces and materials in order to gain a better understanding of the
challenges involved with the in situ environments of the target analytes. In addition we looked into
bioanalyte targets and the use of cantilever sensors as a replacement for conventional light detectors. In
our software efforts, we made initial progress towards providing absolute detection (without reference
signal) and algorithms for identification of chemicals using multiple peaks. Hardware improvements
included the design and construction of four QCLs in a signal assembly.
Program Development
Many program managers visited ORNL for live demonstration. We are confident that success of this
project will result in follow on funding from many agencies including the Joint Improvised Explosive
Device Defeat Organization (JIEDDO), the U.S. Air Force, Army, Navy, and the Department of
Homeland Security (DHS). In addition, we are receiving solid interest from industry on the IP involved in
this technology. We have also received interest from U.K. Ministry of Defense. Our JIEDDO program
manager, Dr. Mike Rafailov, is extremely interested in standoff imaging. However, he needs preliminary
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