An excimer laser apparatus according to the present disclosure includes a chamber configured to accommodate a laser gas and a pair of electrodes and generate pulse-oscillating laser light when the gas pressure of the laser gas is controlled in accordance with voltage applied between the pair of electrodes, a power supply configured to apply the voltage between the pair of electrodes, and a controller to which a target value of the spectral linewidth of the laser light is inputted, the controller configured to correct the voltage used to control the gas pressure, when the target value changes from a first target value to a second target value, based on a first function having the second target value as a parameter and control the gas pressure in accordance with the corrected voltage.

A laser chamber apparatus may include a pipe, an inner electrode extending along a longitudinal direction of the pipe and disposed in a through hole in the pipe, an outer electrode including a contact plate extending along the longitudinal direction of the pipe and being in contact with an outer circumferential surface of the pipe and a ladder section formed of bar members each having one end connected to the contact plate and juxtaposed along a longitudinal direction of the contact plate, and a leaf spring extending along the longitudinal direction of the pipe and configured to press the outer electrode against the pipe. The leaf spring may include leaf spring pieces separated by slits, and the leaf spring pieces may each include a bent section bent along the edge and are configured to press the bar members in a position shifted from the bent sections toward the edge.

A laser cutter and safe power system therefor are disclosed. The power system of the laser cutter includes a resistive device arranged in a return line and configured to prevent anomalous tripping of a GFCI device by significantly minimizing electrical noise transmitted through the GFCI device when the laser cutter is operated in certain modes, such as a pulsing mode. The resistive device includes end caps that form a shroud around the connection between a return wire and the contact at each end of the resistive device. A main control board for a high voltage subsystem of the power system includes two isolated and independent enable signals, which are provided to different controllers on the main control board such that the different controllers can independently and redundantly respond to an unsafe condition.

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.

A multi-pass coaxial molecular gas laser is described in both symmetrical and asymmetrical configuration. An anode vessel receives lasing gas and the gas flows through one or more plasma channels to a cathode vessel which receives the gas and redirects it in the closed system. A second anode vessel may alternatively be provided to double length of the plasma channel and increase surface area exposure of the optical beam to the energized gas. Non-laminar gas flow may be created using spiral nozzles at the entrance of the optical resonator.

Online calibration of laser performance as a function of the repetition rate at which the laser is operated is disclosed. The calibration can be periodic and carried out during a scheduled during a non-exposure period. Various criteria can be used to automatically select the repetition rates that result in reliable in-spec performance. The reliable values of repetition rates are then made available to the scanner as allowed values and the laser/scanner system is then permitted to use those allowed repetition rates.

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 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 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.