The vacuum metal deposition is divided into several process steps. At first, the exhibit is put into a high-vacuum cabin. There, gold particles are evaporated onto the exhibit. These particles stick to the exhibit only, but not at all to the fingerprint: The skin fat of the fingerprint prevents the particles from sticking to the surface.
Ninhydrin is a chemical compound which proves the presence of amino acids and specific proteins. When Ninhydrin gets in contact with those substances, it reacts with creating a blue violet-red brownish colorant which makes them visible. The product of this blue violet reaction was described by Ruhemann in 1911 for the first time. Thus, it refers to the name of “Ruhemanns Purpur”.
NIST, better known as the National Institute of Standards and Technology, is a part of the U.S Commerce Department. NIST develops and promotes measurement standards. It also supports industry and science in implementing these standards. The corresponding standard allows the consistent exchange of many features with the fingerprint itself. Also, it provides information about the recording department and the applied technology.
Next Generation Identification (NGI) is a project of the FBI and gradually replaces the IAFIS in the United States. Through improved software and search algorithms, the new database records both palm prints and data of the iris of the eye for face recognition.
The concluding NAS-Report is a document of 254 pages and contains many observations and recommendations regarding forensic science. Furthermore, it criticizes the way the community conducts its business.