Rapid Visualization of Biological Fluids at Crime Scenes using Optical Spectroscopy

This project will develop a rapid and nondestructive tool for visualization of blood and semen at crime scenes. A prototype portable camera will be designed using mid-infrared (IR) spectroscopy and a novel detector sensitized to locate biological fluids including blood and semen on common surfaces. The imaging device will use a modified thermal array detector with a spectral response primarily determined by the absorbance of a polymer film, turning the detector into a spectral correlator. This will be achieved by modifying the detector with a metal mirror followed by the polymer film so that the film absorbances are responsible for most thermal conversion. By using polymers that mimic the spectral signatures of biological fluids of interest (blood, semen, saliva, and urine), the location of deposits of these fluids can be detected even in the presence of potential interferents that might be expected at crime scenes.

ca/ncf