Standoff Detection and Imaging Using Point-and-Line-CARS

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Highly Sensitive Standoff Molecular Detection and Imaging Using CARS

Princeton Docket # 13-2867-1


Researchers in the Department of Mechanical and Aerospace Engineering at Princeton University use a technique (CARS) to provide real-time detection of trace amount of solids at range.


Real-time spectroscopy and detection of trace species is very challenging due to the difficulties to achieve both selectivity and sensitivity. Raman vibrational spectroscopy has been proven to give exceptional molecular identification, but the sensitivity is low. For standoff detection a very sensitive method is needed. Other methods such as LIDAR and LIBS can achieve range detection, but they cannot identify small quantities of complex molecules. This innovation is a device that has sensing capability for standoff molecular detection of solid or liquid traces in real-time based on Coherent Anti-Stokes Raman Spectroscopy (CARS), which provides many orders of magnitude higher sensitivity than Raman spectroscopy. In this device, CARS system is modified such that the beams are broadband, collinear and time-delayed in order to obtain single-shot background-free spectra. The beams can also be focused into the sample in a line rather than a single point, and CARS spectra is recorded from all the points along the line at the same time in a configuration called LINE-CARS. A spectrometer/CCD camera detection system collects the CARS signal, and a computer compares the spectra with a library spectra. A decision is made and identification of targets is provided in real-time. LINE-CARS enabled fast hyper-spectral imaging of the target in real-time.

The device has a portable version, which uses the same combination of laser pulses but from a fiber-based system. It is used for proximity detection and classification. The inventors have obtained CARS spectra with clear Raman lines for the bacterial spores and biological samples in milliseconds. By comparing the CARS spectra of tissue of interest with the spectra of specific pathological tissue and normal tissue, the device is able to realize real-time biopsy for obtaining complete surgical margin control during removal of cancer. During Mohs surgery to remove skin cancer, CARS device can be utilized to greatly simplify the biopsy procedure and provide results in milliseconds. The device can also be used to detect precancerous conditions.



•       Identification of variety of molecules on a surface from a distance

•       Real-time chemical detection

•       Environmental

•       Food spoilage detection

•       Real-time biopsy analysis

•       Thin film, real -time chemical diagnostics

•       Defect monitoring

•       Food spoilage  detection

•       Forensics

•       Mold spore detection

•       Mining and extraction



•       Real-time detection

•       High sensitivity and selectivity

•       Wide area detection

•       Hyper-spectral imaging

•       Sample remains unchanged and can be used for other tests



Arthur Dogariu received his PhD in Optical Physics from the School of Optics/CREOL, University of Central Florida in 1997. His research experience includes experimental optical physics in the areas of nonlinear and ultrafast optics, biomedical optics, biosensors, remote detection techniques, plasma dynamics, photo-physics of organic materials and devices, time-resolved spectroscopy, nano-optics, quantum optics, wave propagation in dispersive media. Dr. Dogariu is currently a Research Scholar and lecturer at Princeton University, where he has developed a hybrid coherent Raman spectroscopy (CARS) diagnostic method used for fast remote sensing, detection and identification of molecular species. Dr. Dogariu has over 170 publications with a citation index over 4,000. He was the US Scientific Advisor for Institute of Physics (IOP) Publishing, and has served as editor and reviewer for many journals.


Intellectual Property & Development status

Patent protection is pending.

Princeton is currently seeking commercial partners for the further development and commercialization of this opportunity.




Michael R. Tyerech

Princeton University Office of Technology Licensing • (609) 258-6762•

Sangeeta Bafna

Princeton University Office of Technology Licensing • (609) 258-5579•


Patent Information:
For Information, Contact:
Chris Wright
Licensing Associate
Princeton University
Arthur Dogariu