Device and method for showing potential trace by means of far infrared rays

Abstract

The invention discloses a device and method for showing a potential trace by means of far infrared rays to solve the problem that the potential trace on paper is hard to extract. The device comprises a main table, a far infrared treatment table, a laser power supply and pump and an evidence obtaining device, wherein an oblique table used for installation of the evidence obtaining device is arranged on the main table, the far infrared treatment table is arranged in the main table and used for conducting far infrared treatment on an object to be detected, perspiration matter permeating through the paper is crystallized into a trace in the small crystal particle mode from fiber intervals after the object to be detected is treated with far infrared rays, laser emitted by the laser power supply and pump irradiates the object to be detected treated with far infrared rays to enable the trace formed in the crystallized mode on the object to be detected to emit fluorescent light so that the potential trace can be shown, and the evidence obtaining device is used for taking a photo of the shown trace to extract the trace. According to the device and method, perspiration matter permeating through the paper can be shown in the small crystal particle mode from fiber intervals on the premise that the integrity of the permeable paper is kept, fluorescent light is emitted under the excitation of laser with a specific spectrum, the potential trace is shown on the paper without damage caused, and evidence obtaining quality is improved.

Description

technical field [0001] The invention relates to a technique for extracting latent traces, in particular to a device and method for displaying latent traces by using far infrared. Background technique [0002] Latent prints Fingerprints are made up of a mixture of sweat and oil. Among them, the water content of sweat is about 99.0%-99.5%, and the remaining 0.5%-1% is solid matter. 50% of solid matter is organic matter, 50% is inorganic salt (sodium chloride), and an important part of organic matter is amino acid. [0003] For the paper produced by plant fibers, because there are a large number of capillary pores between the fibers themselves and the fibers, and the cellulose and hemicellulose that make up the fibers contain a large number of hydrophilic hydroxyl groups, it is easy to absorb water and other liquids and remain on the paper. The content of organic substances such as amino acids on the surface is very small, so it is extremely difficult to extract sweat traces ...

AI Technical Summary

Problems solved by technology

[0003] For the paper produced by plant fibers, because there are a large number of capillary pores between the fibers themselves and the fibers, and the cellulose and hemicellulose that make up the fibers contain a large number of hydrophilic hydroxyl groups, it is easy to absorb water and other liquids and remain on the paper. The content of organic substances such as amino acids on the surface is very small, so it is extremely difficult to extract sweat traces (such as fingerprints, palm prints, etc.) from permeable paper, that is to say, it is difficult for existing trace extraction equipment to achieve Non-destructively reveal potential traces on

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