Forensic comparison analysis of plastic vehicle headlamp lens by gel permeation chromatography and statistical methods

Abstract

Vehicle headlamps are mounted in front part of vehicles and easily exposed to collision. Lens fragments of headlamps are often encountered in traffic accidents and vehicle-involved cases, which provide an important form of trace evidence in forensic investigations. The value of headlamp lens fragments in forensic investigations has been recognized for many years. Comparisons between vehicle headlamp lens fragments collected from the crime scene and from the suspected vehicles can help identify a vehicle involved in a hit-and-run incident [1]. At early days, vehicle headlamp lenses were made of glass. A lot of studies, utilizing a wide variety of analytical instrumentation including refractive index [2,3], scanning electron microscope coupled with energy dispersive x-ray