How is the light amplified in the laser system?

The laser system uses an optical resonator to amplify and orient the light. This is a cylindrical chamber filled with the laser medium. There are mirrors on each end and an absorptive lining. The photons of light are reflected between the mirrors. The lining will absorb any light that is not perfectly parallel. These parallel photons continue to enter additional atoms, producing more photons by stimulated emission. By this process, the laser light is amplified. One end of the optical resonator has a mechanism to release the light periodically from the chamber.