Citation

Edmondstone G. J. Can. Soc. Forensic Sci. 1997; 30(4): 181-184.

Copyright

(Copyright © 1997, Canadian Society of Forensic Science, Publisher Informa - Taylor and Francis Group)

DOI

10.1080/00085030.1997.10757096

PMID

unavailable

Abstract

An unusually large change in refractive index after re-annealing (ΔRI), 0.00106, was observed in a sample of windshield glass submitted in a case. The manufacturer of this windshield indicates that a minority of windshields is produced by the press bend method and that this results in glass with higher stress than is normal in non-tempered glass. Known samples of press bend glass were also found to have a similarly large ΔRI after re-annealing. A total of 94 samples of windshield glass were examined with 83 found to have a ΔRI in the normal range for non-tempered glass and 11 having a ΔRI above this range. This is a previously unreported property by which windshield glass can be classified by forensic scientists.