System for actively controlling a cavity length of an optical assembly

A system comprising:

• an optical assembly comprising:
• a first optical element comprising a first curved optical surface;
• and
• a second optical element comprising a second curved optical surface, wherein the first curved optical and the second curved optical surface define at least a portion of an optical cavity;
• a sensor configured to produce data related to at least two pulses of light that exit the cavity;
• and
• a control system configured to control a position of one or more of the first optical element and the second optical element based on data from the sensor to thereby compensate for changes in a radius of curvature of one or more of the first curved optical surface and the second curved optical surface.

A control system configured for use with an optical pulse stretcher, the control system comprising:

• a data analysis module configured to:
• analyze data from a sensor, wherein the sensor is configured to sense at least a portion of two or more pulses of light that exit an optical cavity at different times, and wherein, to analyze the data, the data analysis module is configured to:
• determine one or more properties of at least two of the pulses of light based on the data from the sensor;
• and
• the control system further comprises an actuation control module configured to:
• determine a command signal for an actuation system coupled to the optical cavity based on the one or more properties;
• and
• provide the command signal to the actuation system to adjust a length of the optical cavity.

An optical system comprising:

• an optical oscillator configured to emit an amplified pulsed light beam on a beam path;
• a pulse stretcher configured to be placed on the beam path, the pulse stretcher comprising:
• a first optical element comprising a first curved optical surface;
• and
• a second optical element comprising a second curved optical surface, wherein the first curved optical and the second curved optical surface define a cavity;
• a sensor configured to produce data related to at least two pulses of the amplified pulsed light beam that exit the cavity;
• and
• a control system configured to control a position of one or more of the first optical element and the second optical element based on data from the sensor to thereby compensate for changes in a radius of curvature of one or more of the first curved optical surface and the second curved optical surface.