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Just Science Podcast: Just 3D Optical Topography

NCJ Number
Date Published
4 pages

This website provides access to a podcast - one in a series on forensic science sponsored by the National Institute of Justice's Forensic Technology Center of Excellence - that features interviews with Dr. Ryan Lilien (from Cadre Forensics) and Todd Weller (from the Oakland Police Department) on their groundbreaking research in optical topography and firearms identification.


Optical topography is a means to give firearms examiners data that is close to a perfect 3D representation of an object or impression. The research described provides the possibility that in the future it will be possible to relate the examiner's judgment to a statistical representation. The podcast interview includes a detailed description of the procedure and product of 3D optical topography, with attention to its use with cartridge casings in the research conducted by Lilian and Weller. Related software from this research is available for download.

Date Published: January 1, 2017