Fingerprints on firearm cartridges discerned with novel lens systsem
25 July 2012Tweet
A forensics equipment company, Consolite Forensics (Zeals, UK), has integrated a novel custom lens from Resolve Optics into its Cartridge Electrostatic Recovery and Analysis (CERA) system. The CERA technology is now able to extract fingerprints from discharged cartridge cases, not visible by any other means.
The scenes of many crimes involving firearms, where spent cartridge cases are the only evidence recovered, has traditionally posed a particular challenge for forensic scientists. Using fingerprints, caused by corrosive sweat, on brass metal cartridge cases has enjoyed some recent success in producing identifiable fingerprints where conventional techniques have failed.
After insertion of the spent cartridge case, the Consolite CERA system starts out by automatically measuring the size and shape of the casing, and then distributes a powder over the surface in a uniform and carefully measured way. The powder is attracted to areas of surface corrosion caused by chemicals in the fingerprint deposit. Once a clear print is obtained, the CERA camera, fitted with Resolve Optics lens, collects a number of high resolution images from the circumference of the cartridge and downloads them to special imaging software to create a fingerprint for identification.
Mark Pontin, managing director of Resolve Optics, commented: ‘Consolite approached us to develop a custom lens to provide the correct magnification and the required depth of field for their CERA system to optimally operate. We worked closely with Consolite to ensure the special lens we developed provided a 10 Megapixel image and maintained the correct geometry free of any optical distortions.’