What are bullet proof glasses made of?« Back to Questions List

Bullet proof glasses are known as ballistic glass. For security reasons, a president of a country addresses the nation from within a bullet proof podium; a very important person like a chief minister passes by in a bullet proof car. So what is it supposed to do and how are they made?

A bullet proof glass is supposed to stop bullets hitting the surface of glass. Bullet proof glasses are two layers of glasses with a layer of transparent plastic between them. The plastic layer is made of polycarbonate which is tough and transparent. The process of layering a polycarbonate material within two layers of glass is called lamination. The material that is produced after lamination is quite thick compared to an ordinary layer of glass.

When the glass is shot at, the layer of glass hit by the bullet absorbs some of the bullet’s energy. This layer is brittle and shatters at the place it is hit. The next tough plastic layer absorbs the remaining energy of the bullet and stops it so that it doesn’t pierce through the last layer of glass.

Bullet proof glasses come in different thickness ranging from 7 millimeters to 75 millimeters. Depending on the needs, glass thickness is varied.

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