Nederlands Forensisch Insituut: InfiniteFocus in Forensics
René Pieterman, forensic scientist and specialist on invasive traumas, gives an insight into how 3D surface metrology contributes to crime detection.
The Netherlands Forensic Institute is under the jurisdiction of the Dutch Department of Justice and has about 40 areas of expertise. InfiniteFocus is used for many types of cases that are investigated for the police, lawyers, the ministry of armed forces etc. Some typical fields of forensic expertise are Pathology, Anthropology, Toxicology, Chemistry, Balistics, Fibers, Documents, Handwriting, Narcotics, Explosives, DNA, Marks etc.
Why is 3D surface measurement necessary for crime detection? Why is InfiniteFocus the appropriate tool for you?
Modern forensics cannot work without 3D surface analysis. Our department has to examine all kind of features related to tools, objects, weapons etc. We also deal with marks on victims’ bodies. InfiniteFocus was purchased for a specific reason. We were looking for a system for the examination and comparison of tissue, bones etc. of human corpses with tools, objects, weapons etc. Particularly, the system is used to measure tissue and bone damage and the corresponding implements of the crime.
How would you describe the typical surface condition of bones and tissue?
When investigating human or animal bones, we usually face rather difficult surfaces that show very steep flanks. Also, weapons or synthetics with reflecting metals were difficult to view and measure before we worked with InfiniteFocus. This is the main reason why we purchased the Alicona measurement device. It is the perfect tool to measure in a high resolution even with difficult surface conditions.
What other surfaces are measured with InfiniteFocus?
As the system can be used for most surfaces we use it for various applications. Consequently, the type of materials investigated by InfiniteFocus is numerous and includes the 3D measurement of metals, wood, synthetics, bullets, tape, tissue, bones etc.
What are the special benefits of the system? What is in your opinion the most distinctive feature?
One of the most important aspects for our work is light and illumination. The combination of axial and ring light enables the high resolution measurement of the various reflective surfaces. Also, the system fills the gap between regular optical microscopes and the SEM. With InfiniteFocus, we are now able to measure down to a resolution of 10nm!