This crucial laser glass amplifies the laser light to the very high energies required for fusion experiments. NIF uses about 3,070 large plates of special phosphate glass doped with neodymium atoms.

A split second before the initial weak laser pulse comes along, more than 7,500 lamps energize the neodymium atoms in the glass by flashing an intense white light on them. The energized atoms then emit photons as the weak laser pulse passes through the glass slabs, allowing the laser beam to pick up trillions of extra photons.