摘要

A high-resolution and universal method for the rapid visualization of latent fingermarks on a broad variety of surfaces has been achieved by simply combining hydrophilic cellulose membrane with dye aqueous solution. In this approach, the relatively hydrophobic characteristic of fingermark residue enable the deposit act as a "mask", directing dye absorption processes to regions of both furrows without the ridge residues and bare cellulose membrane substrate. This effect during the spatially selective dye absorption generates a negative pattern of the fingermark within a few seconds to minutes depending on the properties of the substrates and fingermark types. It provides observation of latent fingermarks on cellulose membrane surface with high definition of level 2 and level 3 details used for personal identification purposes. It is also highly-efficient for visualizing the latent fingermarks lifted from various common (glass, carton, ceramic cup) and problematic (banknote, human skin and leather) surfaces by using transparent adhesive tape. To examine the generality of the proposed method, eight different kinds of dye aqueous solutions have been tested for developing latent fingermarks and they all provide very good results as expected. Moreover, this approach is easily used for aged fingermarks and natural fingermarks as well. Imaging may be accomplished visibly (by dye color) and topographically (using a microscope or a camera). This approach is a simple, rapid, non-destructive, safe, low-cost, universal and high resolution method compared with conventional approaches, so it demonstrates good potentiality in individual identity validation related applications.