NCJ Number
252211
Date Published
October 2018
Length
2 pages
Annotation
This report summarizes a research project funded by the National Institute of Justice (NIJ) that sought to develop a compact, lightweight camera capable of simultaneous imaging at both visible and near-infrared wavelengths.
Abstract
Although earlier efforts to achieve this goal showed promise, the technical challenges of weight, cost, complexity, ruggedness, portability, and user friendliness have kept this technology from being useful to crime-scene investigators. The current project addressed these challenges by developing a compact, lightweight camera capable of simultaneous imaging at both visible and near-infrared wavelengths. The device was developed by using multiple cameras linked to mini-computers combined into one unit. Although the miniaturization of off-the-shelf cameras and mini-computers did not progress as rapidly as hoped by the researchers, they did succeed in creating a Dichroic camera that can capture 16 spectral colors in the 400-1,000 nanometer range. Researchers tested the utility of the camera system on latent blood stains and fingerprints. Multi-spectral images were acquired under various conditions for different surfaces, including dark cloth, leather, and paint. Multi-spectral imaging is designed to synthesize image data, enabling the user to view details far beyond what can be seen by the human eye. Although washing cloth in a household washing machine removed all evidence of stains, except on white fabrics, less effective forms of cleaning left sufficient residues of the stains that were detected by the camera. Researchers reported that attempts to locate and identify latent fingerprints with the multi-spectral camera showed "some successes, some failures, and some inconclusive results." Thus, they concluded that the multi-spectral imaging of fingerprints is not a promising technology for the crime-scene investigation of fingerprints. They further advise that the next step should be to determine whether a multi-spectral camera can locate blood, semen, or other stains at a crime scene.