Detecting Surface Stains Using High Absorbance Spectral Regions in the mid-IR

Description:

Reference #: 00826

The University of South Carolina is offering licensing opportunities for this technology.

Invention Description:

The subject invention provides a non-destructive, hands-off technique for the detection of surface coatings in trace concentrations, coatings that are often times invisible to the naked eye. These types of surface stains are detected in the Mid-IR by using high absorbance spectral regions. The method coordinates a thermal infrared sensor or camera and a light source to detect surface films, coatings, or contaminants in concentrations as low as 90 ng/cm2.

Background:

Most materials absorb strongly in the fundamental IR spectral region (e.g. 3-20 μm). In regions of fundamental absorbance, the absorption in these bands is so strong that the measured reflectance contains only specular reflection, reflection that is surface-dominated. Any photons that penetrate the surface are absorbed and, therefore, not re-emitted. While there is only a small change in the spectrum, the specular reflectance changes substantially when a thin surface coating is present.

Potential Applications:

Forensic science is one field that would benefit from this method allowing detection of:

· Latent prints

· Gunshot residue

· Drug contamination

· Fire and explosives

· Counterfeit documents

Advantages and Benefits:

· Non-destructive (doesn't disrupt or destroy sample/area)

· Hands-off (does not have to come in contact with surface)

· Sensitive enough for trace concentrations/coatings

More Information: