Research on the Occurrence Patterns of Close Non-matches on Central and Branch Regions of Loop

The presence of close non-matches poses inherent risks to fingerprint identification, and exploring their occurrence patterns in different regions of the fingerprint can enhance the risk awareness of identification personnel. To investigate this, 30 fingerprints from the central and branch regions of loops were selected as research subjects. Each fingerprint was queried 15 times within a database of ten million individuals to examine the occurrence of homologous fingerprints and close non-matches when 6 to 20 minutiae were marked. The results revealed that close non-matches could be found in both the central and branch regions of loops when 6 to 20 minutiae were marked, and notably, the number of close non-matches in the branch region was significantly higher than in the central region. The proportion of homologous fingerprints ranked higher than close non-matches in the central and branch regions of loops, with respective percentages of 98.4% and 60.9%. Even when 20 minutiae were marked, there were still instances where homologous fingerprints did not appear in the branch region of the loop. Frequency analysis of similar regions indicated that the side of the central region facing the loop and the side of the branch region facing the branch were more susceptible to having close non-matches. Additionally, high-level close non-matches with over 10 matching points were identified in both the central and branch regions of loops. Therefore, fingerprint identification personnel must handle close non-matches with caution to prevent them from interfering with accurate identification.