NCJ Number
207269
Journal
Journal of Forensic Identification Volume: 54 Issue: 5 Dated: September/October 2004 Pages: 560-571
Date Published
September 2004
Length
12 pages
Annotation
This article describes a field methodology for photoluminescence detection of traces of explosives and latent fingerprints.
Abstract
The field prototype instrumentation described in this article uses a laser (532 nm, 130 mW, Model 532 GBD, B.E. Meyers & Company) powered by three flashlight batteries. For explosive detection, the prototype is equipped with a sample holder onto which the filter paper with the evidence sample and the reference blank are placed. As with photoluminescence techniques generally, background fluorescence often masks the photoluminescence of interest. These occasions call for time-resolved visualization that suppresses the background. The instrumentation for this procedure is described. Figures show the difference between a masked photoluminescence result of an explosive sample using standard instrumentation compared with the result from time-resolved instrumentation. Figures and commentary are also presented to show the difference between the result of the photoluminescence of a latent fingerprint on a magazine cover by ordinary fluorescence excitation (masked to the extent of no visible fingerprint detail) and the use of time-resolved fingerprint detection to suppress the background and reveal the detail of the fingerprint. 8 figures and 7 references