During operation, the energy monitor provides pulse energy information to the laser control computer. If the energy varies, the computer increases or decreases the high-voltage supply set point to change the laser light output. When the high-voltage level reaches the allowed maximum, the laser gas mixture must be adjusted to increase lasing efficiency. To stabilize the output over a reasonable time and to provide headroom for high-voltage adjustment, the initial energy set point must be approximately 60% of the maximum laser output.
Laser energy stabilization loop conceptual diagram