Disclosed is a laser discharge chamber in which useful lifetime is extended by local electrical tuning using one or a combination of design of the chamber internal geometry, placement and distribution of components within the chamber such as electrodes, current returns, and capacitors, and selective electrical isolation of portions of the components.

A gas laser apparatus according to an aspect of the present disclosure includes a main discharge circuit that supplies main discharge voltage that causes main discharge to a pair of main discharge electrodes, and a pre-ionization circuit that supplies pre-ionization voltage that causes corona discharge to a pre-ionization electrode. The main discharge circuit includes a step-up pulse transformer, a main capacitor and a switch connected to a primary side of the step-up pulse transformer, a first power source that charges the main capacitor, a first capacitor connected in parallel to a secondary side of the step-up pulse transformer, a first magnetic switch connected to the first capacitor, and a peaking capacitor connected in parallel to the first capacitor through the first magnetic switch and to the main discharge electrodes. An interval between start timings of the corona discharge and the main discharge is 30 ns to 60 ns inclusive.

A gas laser apparatus according to an aspect of the present disclosure includes a main discharge circuit that supplies main discharge voltage that causes main discharge to a pair of main discharge electrodes, and a pre-ionization circuit that supplies pre-ionization voltage that causes corona discharge to a pre-ionization electrode. The main discharge circuit includes a step-up pulse transformer, a main capacitor and a switch connected to a primary side of the step-up pulse transformer, a first power source that charges the main capacitor, a first capacitor connected in parallel to a secondary side of the step-up pulse transformer, a first magnetic switch connected to the first capacitor, and a peaking capacitor connected in parallel to the first capacitor through the first magnetic switch and to the main discharge electrodes. An interval between start timings of the corona discharge and the main discharge is 30 ns to 60 ns inclusive.

A laser system for amplifying laser light generated from a laser light source and emitting the laser light includes an optical element in an optical path of the laser light and transmits the laser light, a control device to control power to be supplied to the laser system, an imager to capture an image of the optical element, and an image processing circuitry to process the image of the optical element captured by the imager. The image processing circuitry in which reference images of the optical element corresponding to power information relating to the power are prepared in advance includes a comparison unit to compare a captured image of the optical element captured by the imager with a reference image selected by a reference image selection unit, the reference image corresponding to the power information at a time of image capturing by the imager.

A laser system for amplifying laser light generated from a laser light source and emitting the laser light includes an optical element in an optical path of the laser light and transmits the laser light, a control device to control power to be supplied to the laser system, an imager to capture an image of the optical element, and an image processing circuitry to process the image of the optical element captured by the imager. The image processing circuitry in which reference images of the optical element corresponding to power information relating to the power are prepared in advance includes a comparison unit to compare a captured image of the optical element captured by the imager with a reference image selected by a reference image selection unit, the reference image corresponding to the power information at a time of image capturing by the imager.

A laser radiation system according to a viewpoint of the present disclosure includes a first optical system configured to convert a first laser flux into a second laser flux, a multimirror device including mirrors, configured to be capable of controlling the angle of the attitude of each of the mirrors, and configured to divide the second laser flux into laser fluxes and reflect the laser fluxes in directions to produce the divided laser fluxes, a Fourier transform optical system configured to focus the divided laser fluxes, and a control section configured to control the angle of the attitude of each of the mirrors in such a way that the Fourier transform optical system superimposes the laser fluxes, which are divided by the mirrors separate from each other by at least a spatial coherence length of the second laser flux, on one another.

A high-voltage pulse generation device configured to apply a pulsed high voltage to the space between a pair of discharge electrodes disposed in a laser chamber of a gas laser apparatus includes n transformer cores that form a transformer, where n is a natural number greater than or equal to two, n primary electric circuits of the transformer, the n primary electric circuits each having a first terminal connected to a reference potential and a second terminal connected to a charger, the n primary electric circuits each including one or more primary coils, one or more diodes connected in parallel to the one or more primary coils, and one or more pulse generators connected in parallel to the one or more primary coils, and a secondary electric circuit of the transformer, the secondary electric circuit including a secondary coil and connected to the pair of discharge electrodes.

A high voltage pulse generation device includes n transformer cores configuring a transformer, n being a natural number of 2 or more, each of the n transformer cores being configured to form a magnetic circuit along a first plane and to have a width in a first direction parallel to the first plane larger than a width in a second direction parallel to the first plane and perpendicular to the first direction; n primary electric circuits of the transformer connected in parallel to each other, each of the n primary electric circuits including at least one primary coil, and m pulse generation units connected in parallel to the at least one primary coil, m being a natural number equal to or more than 2; and a secondary electric circuit of the transformer including a secondary coil and connected to a pair of discharge electrodes.

The present invention provides a laser, including: a medium, having a ground state, an intermediate state, and an excited state in ascending order of energy; an excitation system, configured to excite electrons in the medium from the ground state to the intermediate state; and an excitation laser, configured to drive electrons in the intermediate state at different spatial positions in the medium to the ground state through a stimulated emission process with a fixed phase relationship, to generate a laser with a shorter relative wavelength. Due to the use of an excitation laser to drive electrons from the intermediate state, the photons generated by the stimulated emission have coherence, thereby forming a laser. In the present invention, an excitation system performing primary pumping combined with an excitation laser with a relatively long wavelength performing secondary pumping generate lasers with a relatively short wavelength, and the structure of the short-wavelength laser is simple, compact, and easy to be implemented. In addition, the cost of the short-wavelength laser can be reduced, and a laser with a shorter wavelength can be obtained.

A light emitting unit includes a light emitting sealed body and a voltage application circuit. The light emitting sealed body includes a container to which laser light for maintaining plasma is incident and from which light from the plasma is emitted, a first electrode which includes a first discharge portion, and a second electrode which includes a second discharge portion. An end portion of the first discharge portion has a shape in which a thickness is thinned as it goes toward the second discharge portion and an end surface of the second discharge portion extends along a plane perpendicular to an extending direction of the first discharge portion. The voltage application circuit controls a potential difference between the first electrode and the second electrode by adjusting a voltage applied to at least the first electrode.