What is bulletproof glass made of?

Bulletproof glass, or bullet-resistant glass, is a composite material made from layers of tough, transparent materials bonded together. The most common construction involves layers of tempered glass alternating with layers of plastic, such as polycarbonate or polyvinyl butyral (PVB). The glass layers provide hardness and clarity, while the plastic interlayers provide flexibility and energy absorption. When a bullet hits the glass, the hard outer layer is designed to flatten the projectile and begin dissipating its energy. As the bullet moves through the subsequent layers, the plastic interlayers stretch and absorb the remaining kinetic energy, preventing the bullet from penetrating all the way through. Some modern bullet-resistant products use glass-clad polycarbonate, which offers superior protection with less weight and thickness than traditional all-glass laminates. For higher levels of protection, the number of layers and the total thickness increase. The goal is to create a material that is hard enough to deform the bullet but resilient enough to not shatter completely upon impact. This combination of materials allows the window to remain relatively clear while acting as a powerful shield against high-velocity threats.