NCJ Number
86595
Date Published
1981
Length
47 pages
Annotation
A series of experiments measured the effects on fingerprint image quality of the type of paper and ink used to record the fingerprint.
Abstract
Fingerprint images were made using some combination of four types of card stock and four inking techniques. In addition, three types of card stock were used with an inkless chemical fingerprint recording process. All images were of a single finger, the author's number seven. Plain prints, rather than rolled, were taken to minimize plastic deformation and the likelihood of smudging or smearing. The fingerprint images were scored by a computerized matching process that uses the minutiae detected by machine reading different impressions of the same fingerprint. For each image recording process, a sample of 56 finger pairs were matched and mean single-finger score values were developed. These varied over a factor of more than 70 to 1. The best scores were developed from images placed on very white, slick, calendared card stock with the use of filmstrips that had been preinked and which could be separated to expose an ink film of predetermined thickness and uniformity. This combination had less resistance to smearing than fingerprints produced on the same stock from the use of a preinked porous pad; however, the latter still produced acceptably high scores. Tabular and photographic data are provided, along with two bibliographic listings.