NCJ Number
226296
Journal
Forensic Magazine Volume: 6 Issue: 1 Dated: February/March 2009 Pages: 37-40
Date Published
February 2009
Length
4 pages
Annotation
This article explains how easy accessibility to 3D scanning technology makes it possible for any forensic lab to make a permanent 3D record of evidence for analysis and transmission without having to alter or risk damage to the actual evidence item.
Abstract
Most 3D scanners today use lasers to measure 3D information. A laser stripe or dot is moved across a target and is photographed by a camera at a slight angle to the laser source. This type of capture method does not touch or change the original physical sample. For fragile or significant evidence that must be protected from alteration, this is a useful procedure. Although 3D scanning is not a new concept, the availability of affordable, portable, and easy-to-operate 3D scanners is now putting this capability within widespread reach. There are two types of 3D scanners used in forensics. Crime-scene scanners capture a large overview map of a crime scene, which is helpful in viewing and analyzing the relative position of objects. New “closeup” 3D scanners capture individual objects in full color and high resolution 3D. This article describes a pioneering hybrid approach to 3D scanning being used by a team of U.S. Federal investigators. It allows them to capture complete crime scenes with selective “3D “closeups” on key features of physical evidence. An innovative use of “3D closeups” is to capture shoe impressions. A complete and highly detailed 3D model of a footprint is captured in less than 15 minutes, much faster than the traditional method of pouring a plaster mold; and the 3D image is much easier to share among forensic analysts than the plaster mold.