A system includes an optical source configured to emit a pulsed light beam, the optical source comprising one or more chambers, each of the one or more chambers configured to hold a gaseous gain medium, the gaseous gain medium being associated with an assumed gas life; at least one detection module configured to: receive and analyze data related to the pulsed light beam, and produce a beam quality metric based on the data related to the pulsed light beam; and a monitoring module configured to: analyze the beam quality metric, determine a health status of the gaseous gain medium based on the analysis of the beam quality metric, and produce a status signal based on the determined health status, the status signal indicating whether to extend use of the gaseous gain medium beyond the assumed gas life or to end use of the gaseous gain medium.

Disclosed is an electrode for a laser chamber comprising an alloy of a first metal having a first free energy of formation with fluorine greater than or equal to the free energy of formation with fluorine of copper, and a second metal having a second free energy of formation with fluorine less than the first free energy.

A radio-frequency excited carbon dioxide (CO.sub.2) or carbon monoxide (CO) gas laser includes two electrodes, which have passivated surfaces, within a sealed housing. Features in a ceramic slab or a ceramic cylinder located between the electrodes define a gain volume. Surfaces of the ceramic slab or the ceramic cylinder are separated from the passivated surfaces of the electrodes by small gaps to prevent abrasion thereof. Reducing compressive forces that secure these components within the housing further reduces abrasion, thereby extending the operational lifetime of the gas laser.

To cool a capacitor including a first electrode and a second electrode, a capacitor cooling structure includes: a conducting part electrically connected with the first electrode; an insulating part that has a first surface including a first position and a second surface including a second position, and is connected with the conducting part at the first position; a first fastening part configured to fasten the conducting part and the insulating part to each other; and a cooling part connected with the second position facing the first position, the conducting part and the cooling part being electrically insulated from each other by the insulating part.

A light source apparatus includes a gas discharge stage including a three-dimensional body defining a cavity that is configured to interact with an energy source, the body including at least two ports that are transmissive to a light beam having a wavelength in the ultraviolet range; a sensor system comprising a plurality of sensors, each sensor is configured to measure a physical aspect of a respective distinct region of the body of the gas discharge stage relative to that sensor; and a control apparatus in communication with the sensor system. The control apparatus is configured to analyze the measured physical aspects from the sensors to thereby determine a position of the body of the gas discharge stage in an XYZ coordinate system defined by an X axis, wherein the X axis is defined by the geometry of the gas discharge stage.

A light source apparatus includes a gas discharge stage including a three-dimensional body defining a cavity that is configured to interact with an energy source, the body including at least two ports that are transmissive to a light beam having a wavelength in the ultraviolet range; a sensor system comprising a plurality of sensors, each sensor is configured to measure a physical aspect of a respective distinct region of the body of the gas discharge stage relative to that sensor; and a control apparatus in communication with the sensor system. The control apparatus is configured to analyze the measured physical aspects from the sensors to thereby determine a position of the body of the gas discharge stage in an XYZ coordinate system defined by an X axis, wherein the X axis is defined by the geometry of the gas discharge stage.

A discharge excitation gas laser device includes: first and second discharge electrodes disposed to face each other; a plurality of peaking capacitors connected to the first discharge electrode; a charger; a plurality of pulse power modules, each one of the pulse power modules including a charging capacitor to which a charged voltage is applied from the charger, a pulse compression circuit that pulse-compresses and outputs electrical energy stored in the charging capacitor as an output pulse to a corresponding peaking capacitor, and a switch disposed between the charging capacitor and the pulse compression circuit; a plurality of output pulse sensors, each one of the output pulse sensors detecting an output pulse output by a corresponding pulse power module; and a control unit configured to control, based on a detection result of each of the output pulse sensor, a timing of a switch signal to be input to a corresponding switch.

A discharge excitation gas laser device includes: first and second discharge electrodes disposed to face each other; a plurality of peaking capacitors connected to the first discharge electrode; a charger; a plurality of pulse power modules, each one of the pulse power modules including a charging capacitor to which a charged voltage is applied from the charger, a pulse compression circuit that pulse-compresses and outputs electrical energy stored in the charging capacitor as an output pulse to a corresponding peaking capacitor, and a switch disposed between the charging capacitor and the pulse compression circuit; a plurality of output pulse sensors, each one of the output pulse sensors detecting an output pulse output by a corresponding pulse power module; and a control unit configured to control, based on a detection result of each of the output pulse sensor, a timing of a switch signal to be input to a corresponding switch.

Disclosed are methods of and apparatus for extending a useful lifetime of a laser discharge chamber in which a polarity of an electrode positioned at a fixed position within the chamber is caused to be positive with respect to the polarity of a second electrode defining a discharge gap with the first electrode and the first electrode is made of a material that forms an erosion resistant surface when the first electrode is used and an anode. Also disclosed is an arrangement in which a first electrode is positionable with respect a second electrode defining a discharge gap with the second electrode and the position of the first electrode controlled to maintain the width of the gap within a predetermined range.

A laser apparatus includes a chamber accommodating a pair of discharge electrodes, a gas supply and exhaust device configured to supply laser gas to an interior of the chamber and exhaust laser gas from the interior of the chamber, and a controller. The controller performs first control to control the gas supply and exhaust device so as to suspend laser oscillation and replace laser gas in the chamber at every first number of pulses or first elapsed time, and second control to control the gas supply and exhaust device so as to suspend laser oscillation and replace laser gas in the chamber before the first control at every second number of pulses less than the first number of pulses or second elapsed time less than the first elapsed time.