CSI Of Glass And Light
How is the analysis of glass used in CSI?
Glass analysis usually comes about when glass is broken, typically during a breaking and entering when fragments of glass will be scattered and perhaps will be caught in the clothing of the perpetrator, and when those fragments are brought back to the crime lab they will be linked, hopefully, by the crime lab technician to the broken glass at the crime scene. This link is normally established by looking at various physical properties of glass such as density and refractive index.
What are the different kinds of glass studied in CSI?
There are generally three types of glass that you will encounter in a crime laboratory. Typically, there is soda lime glass, which is your ordinary window glass or bottled glass, and it is the most common type of glass to be found in connection with a criminal investigation. There's also the type of glasses that emanate from automobiles. The windshield of an automobile will have what we call laminated glass. This would be two layers of soda lime glass sandwiched between a plastic medium. That will give the glass added strength, and that is why it's used in the windshield of a car. The other type of glass that's used in all of the other windows of the automobile, and we call them tempered glass. These glasses have been prepared to withstand fracturing, so that when an impact occurs, they will dice, and they will not fracture and cause jagged edges to be formed that could hurt individuals in the interior of the car.
How can comparison of glass fragments help in CSI?
Glass is typically class evidence and it is used to link a perpetrator to a crime scene. So if a crime scene, for example, occurs with the breaking of glass, and there is some piece of glass, or pieces of glass that are found in the possession of the suspect/perpetrator, the crime lab will attempt to compare those pieces of glass to the broken window at the crime scene. And this comparison is typically carried out by looking at the density and the refracted index characteristics of glass, matching them and comparing them to one another.
How can comparison of glass fractures help in CSI?
