摘要
目的通过自制手印提取胶片对载玻片上不同遗留时间的正常油汗混合重叠手印进行分离提取,提出一种新的重叠手印的分离提取方法。方法使用凝胶(Gel)材料、聚氨酯(PU)基布及聚对苯二甲酸乙二酯(PET)膜制备新型手印提取胶片,用该胶片对不同遗留时间间隔(0.5～24h)的重叠手印进行连续提取并拍照固定,以去除手印纹线之间的相互干扰、实现手印图像的分离;并提出遗留时间差异系数(Td)这一概念,以此初步探究遗留时间对重叠手印胶片分离提取的影响。结果胶片对遗留时间不同的重叠手印进行连续提取可获较好的分离效果,当重叠手印样本的遗留时间差异系数Td≥0.28时,胶片对重叠手印仅进行2～3次的提取即可得到细节清晰、反差较好的单一手印图像。结论利用所制胶片连续粘取分离重叠手印的方法能够有效克服不同遗留时间重叠手印之间的相互干扰,获得质量较好的单一手印图像,该方法具有简单、分离效果好及可信度高等优点,在手印显现研究及实战中有良好的发展、应用前景。
Objective A new gel-lifter is homemade and fi rstly verifi ed to develop overlapped fi ngerprints deposited at different time.Methods T he gel-lifter was made of adhesive gelatin(Gel),polyurethane substrate(PU)and polyethylene terephthalate fi lm(PET).Six sampling overlapped fi ngerprints were deposited onto glass slides with0.5-24h interval.Then the samples were repeatedly lifted by the gel-lifter step by step.A time-interval coeffi cient,Td[Td=(t1-t2)·t2-e],was introduced to analyze the developing results of overlapped fi ngerprints deposited at different time.Results Good effects were shown on developing the overlapped fingerprints when lifted continuously by the gel-lifter.When the time-interval coefficient Td≥0.28,only2or3repetitious gel-lifter lifting can eliminate the interference between the overlapped fi ngerprints,leaving the fi ngerprint images of clear details and high-background contrast.Conclusions The new method of fi ngerprint-lifting by gellifter could effectively eliminate ridge interference and develop single fi ngerprint image from the overlapped fi ngerprints.This method is of simplicity,reliability,and good applicable prospect to be expected.
作者
高峰
张加敏
徐晓
王子政
刘寰
GAO Feng;ZHANG Jiamin;XU Xiao;WANG Zizheng;LIU Huan(Xinjiang Police College,Urumqi830011,China;Coast Guard Academy of Chinese People's Armed Police Force,Ningbo315801,Zhejiang,China;Institute of Forensic Science,Ministry of Public Security,Beijing100038,China;Shanghai Railway Public Security Bureau,Shanghai200071,China;Chinese People's Public Security University,Beijing100038,China)
出处
《刑事技术》
2018年第6期445-448,共4页
Forensic Science and Technology
基金
公安部应用创新计划项目(No.2014YYCXGAES049)
中国博士后科学基金项目(No.2017M620481)
关键词
重叠手印
提取胶片
非渗透性客体
遗留时间
分离提取
overlapped fi ngerprints
gel-lifter
nonporous substrate
age of deposited fi ngerprint
development
