April 13, 2000


Hyperspectral Infrared Imaging can be used to visualize chemical and biological aerosols

The following is a paper presented by Pacific Advanced Technology at MSS Passive Sensors in Charlestown SC. in March, 2000.

Infrared Hyperspectral Imaging Sensor for Gas Detection

Chemical warfare agents in the gas phase are a considerable threat from terrorists anywhere there are enemy forces on a battle field. The ability to detect, identify and determine the direction of propagation of such gases is of considerable interest to the armed forces. With support from the US Air Force and Navy, Pacific Advanced Technology has developed a small man portable hyperspectral imaging sensor with an embedded DSP processor for real-time processing that is capable of remotely imaging gas plums. Then, based upon their spectral signature the species and concentration levels can be determined. This system has been field tested at numerous places including White Mountain, CA, Edwards AFB, and Vandenberg AFB. Recently evaluation of the system for gas detection has been performed. This paper presents these results.

The system uses a conventional infrared camera fitted with a diffractive optic that images, as well as disperses, the incident radiation to form spectral images that are collected in band sequential mode. Because the diffractive optic performs both imaging and spectral filtering, the lens system consists of only a single element that is small, light weight and robust, thus allowing man portability. The number of spectral bands are programmable such that only those bands of interest need to be collected. The system is entirely passive, therefore, easily used in a covert operation.

Currently, Pacific Advanced Technology is working on the next generation of this camera system that will have both an embedded processor, as well as an embedded digital signal processor in a small hand held camera configuration. This will allow the implementation of signal and image processing algorithms for gas detection and identification in real-time.This paper presents field test data on gas detection and identification, as well as discussing the signal and image processing algorithms used to enhance the gas visibility based on principal components analysis. We also present data showing that the instrument can detect gases with a flow rate of less than 0.5 cubic feet per minute. Flow rates as low as 0.01 cubic feet per minute have been imaged with this system.

If you would like to read the full paper, please use the contact information below to request a copy.

For More Information Contact:

Pacific Advanced Technology
1000 Edison St. PO Box 359, Santa Ynez, CA 93460-0359 USA
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