English: This is the final and largest amplifier in the Nike laser. It increases the laser beam energy from 150 Joules to over 5000 Joules. The laser beam enters the gas-filled laser cell through the copper colored 60 cm x 60 cm window, passes through the cell, exits a second window, is reflected by a mirror, and then passes through the cell in the opposite direction. (The mirror is not visible in the photo.) Thus the beam is amplified in each direction. The laser gas is a krypton/fluorine/argon mixture and is excited by two opposing 670,000 volt electron beams. The four transmission lines that drive each electron beam can be seen on either side of the cell. The electron beams are guided by the two large black electromagnets. In this photo, the right hand side of the system has been rolled back to display the electron beam emitter and the high voltage vacuum insulators."