| Fingerprint is the imprinted reflection of the finger mastoid pattern,which is different from person to person,basically unchanged throughout life and the characteristics of contact left traces.Individual identification depends on the particularity and stability of fingerprint.In civil activities,people often use their fingers to confirm the document by taking fingerprints,so as to produce legal effect.Fingerprinting can effectively solve the problem of identity identification and is one of the most reliable basis for identification of individual identity.It is common in litigation cases and plays a crucial role in judicial practice.If the lines are clear,the detailed features and their combination are comprehensive,forensic experts can usually issue an accurate opinion after comparing the characteristics of the fingerprint of the material and the fingerprint of the sample.Fingerprint identification is one of the most common trace identification items in forensic identification of material evidence technology.The content of fingerprint identification mainly includes identification of fingerprint identity,identification of fingerprint formation process,identification of fingerprint formation time and so on.Under normal circumstances,visible fingerprints on paper documents are widespread in identification work related to litigation cases.The use of fingerprint details and their combination is the key to issue fingerprint identification opinions.It is not difficult to make accurate judgment for identification of fingerprint identity with clear lines.But with the development of technology,there are more and more ways to forge fingerprints,and the level of simulation is getting better and better.Although the visible fingerprints to be identified on the document are consistent with the sample fingerprints in terms of pattern,detail characteristics and combination,the specific formation mode of visible fingerprints on the document is not directly formed by finger stamping,so we need to identify the specific formation mode of fingerprint.Identification of the fingerprint formation mode belongs to the identification of the fingerprint formation process.If it is found that the visible fingerprint on the document is not directly formed by the finger,it is of great significance to study the specific formation mode of the visible fingerprint on the document.Fingerprints can be formed by direct stamping and indirect copying.Real fingerprints are formed by direct stamping and forged fingerprints are formed by indirect copying.The traditional ways to forge fingerprints are printing,copying and transferring.In recent years,in the judicial appraisal practice,we found that the visible fingerprints to be identified on documents are forged fingerprints formed by indirect copying,but there are no characteristics of printing,photocopying or transfer,but forged fingerprints made by high simulation.Therefore,it is necessary to study the fingerprint forgery in high simulation.At present,there are few researches on fingerprint forgery in high simulation molding,and most of them only select one kind of molding material for research and analysis.On the basis of objectively summarizing the identification of forged fingerprints,this paper analyzes the characteristics of forged fingerprints by different mould-making methods,discusses the practical value,and systematically studies the identification of forged fingerprints by high simulation mould-making.This paper,including introduction and conclusion,is divided into five chapters as follows:In the introduction part,firstly,the background,research value and significance of the topic selection of high simulation mold forging fingerprints are described theoretically.Secondly,the academic works and literature related to the identification of forged fingerprints were sorted out,and the current research status and further research content of high simulation modeling of forged fingerprints were summarized,and experimental methods were determined.Finally,the paper structure,main innovations and shortcomings of the experimental research on the identification of forged fingerprints in high simulation mould making are described.The first chapter mainly studies the formation of visible fingerprints on documents.By summarizing the formation mode of visible fingermarks on documents,the formation mode of visible fingermarks on documents is classified,and the general method of checking the formation mode of visible fingermarks on documents is proposed,which provides a theoretical basis for the selection of research methods.The second chapter mainly expounds the research basis of forged fingerprint identification,which is divided into three parts.The first part defines and classifies forged fingerprints.The second part introduces the identification of forged fingerprints by traditional methods,starting with the production principles of printing forged fingerprints,photocopying forged fingerprints and transferring forged fingerprints,and explores the characteristics and identification methods of forged fingerprints by three traditional methods.The third part is a simple theoretical introduction to the identification of photosensitive mold forgery fingerprint,silicone mold forgery fingerprint and photosensitive resin mold forgery fingerprint.The third chapter mainly introduces the experimental design of high simulation mold forging fingerprint.Experimental design is a very important content in the experimental research of high simulation mold forging fingerprint,which is divided into three parts.The first part is to select the experimental object,explore the reflection of high simulation mold forging fingerprints under the circumstances of different gender,line width,fingerprint quality and stamping effect.The second part introduces the experimental materials and instruments used in this experiment.The third part is the making and selection of experimental samples.It introduces the principle and method of making fingerprint molds with three different mold materials,and selects the experimental samples for subsequent inspection and analysis in order to achieve the best experimental results.The fourth chapter is mainly about the comparison and research of high simulation molding forgery and direct fingerprinting.The first part is the comparative study of fingerprint surface features,including inkblot features,white leakage features,lines morphological features,variation characteristics and tertiary characteristics.The second part is the comparative study of the fingerprint features,including the fingerprint edge features and the modification of the mold material.The third part is a comparative study of fingerprint 3d features,which is a new test method for fingerprint identification.Through the comprehensive comparison of the three different characteristics of the forged fingerprint and the direct fingerprinting,the objective evaluation is made,which provides a strong scientific support for the problems related to the forged fingerprint in fingerprinting identification practice.The fifth chapter is a summary of the experimental research of high simulation mold forging fingerprints,which is divided into two parts.The first part is to analyze the experimental results.Based on the control variables,the characteristics of fingerprints formed under different printing oils,different pressures and different materials are analyzed.The second part introduces the inspection ideas and matters to be paid attention to the identification of forged fingerprints in high simulation mold making,which provides strong theoretical support for the identification of forged fingerprints in practice.The last part is the conclusion of this paper,which mainly summarizes the whole paper and points out the deficiencies of this experimental study and the problems that need to be further studied in the future. |
