title: A scanning beam time-resolved imaging system for fingerprint detection.
abstract: A highly sensitive confocal scanning-beam system for time-resolved imaging of fingerprints is described. Time-resolved imaging is a relatively new forensic procedure for the detection and imaging of latent fingerprints on fluorescent substrates such as paper, cardboard, and fluorescent paint. Ordinary fluorescent imaging of latent fingerprints on these surfaces results in poor contrast. Instead, the specimens are treated with a phosphorescent dye that preferentially adheres to the fingerprint which allows time-resolved discrimination between the fingerprint phosphorescence and the background fluorescence. Time resolved images are obtained by synchronizing the digital sampling of the specimen luminescence with the on-off cycle of the chopped illumination beam. The merit of this technique is illustrated with high contrast images of fingerprints obtained from the fluorescent painted surface of a Coke can.
authors.affiliation: Physics Department, University of Waterloo, Ontario, Canada.
authors.forename: R D
authors.initials: RD
authors.lastname: Roorda
authors.forename: A C
authors.initials: AC
authors.lastname: Ribes
authors.forename: S
authors.initials: S
authors.lastname: Damaskinos
authors.forename: A E
authors.initials: AE
authors.lastname: Dixon
authors.forename: E R
authors.initials: ER
authors.lastname: Menzel
mesh_terms: D004396:Coloring Agents / Q000494:pharmacology*; D003878:Dermatoglyphics; D005554:Forensic Medicine / Q000379:methods; D006801:Humans; D008163:Luminescent Measurements; D018613:Microscopy, Confocal; D013048:Specimen Handling
chemical_list: D004396:Coloring Agents