Criminology Research Council grant ; (20/87)
Moire patterns formed from a transparent grid over a finger-print might sometimes provide aid for print comparisons because of their particular spatial sensitivity to small deviations between two patterns, particularly when the reference grid is slowly moved over two fingerprints. The specificity of description of these pattern changes is subjective and such that it may be limited to individual expert assessment and may not be practical for a database for general use.
The Moire fringe methods studied in this project appear to be of value only in special cases where conventional methods have difficulties, e.g. minutiae .not registered and where the print specialists may seek additional aids to support their main conclusions. The Moire method appears to be useful on some occasions such as when only a partial print is available and other tests are inconclusive. In the case of a fingerprint on a newspaper where the print matrix of dots obscures or confuses the minutiae detail, image processing may retrieve a print but without sufficient minutiae and which then would benefit from an additional test.
The method of Moire fringes has been tried on prints on a number of different types of surfaces. Their use in actually revealing faint prints is not yet practical but they sometimes can be used on prints of less than desirable quality which have been recovered from latent fingerprints by other means.