A radio-frequency, RF, slab laser 10 with a Z-fold resonator cavity defined by an output mirror 32, a first fold mirror 34, a second fold mirror 36 and a rear mirror 30. The second fold mirror 36 is rotated by an adjustment angle away from the angle it would have if the mirrors were all plane mirrors and directed the round trip beam path by direct reflection. Moreover, the rear mirror 30 is rotated by an adjustment angle that is approximately twice the adjustment angle of the second fold mirror 36. These rotations of the rear mirror 30 and second fold mirror 36 suppresses parasitic mode paths that would otherwise exist.

A radio-frequency, RF, slab laser 10 with a Z-fold resonator cavity defined by an output mirror 32, a first fold mirror 34, a second fold mirror 36 and a rear mirror 30. The second fold mirror 36 is rotated by an adjustment angle away from the angle it would have if the mirrors were all plane mirrors and directed the round trip beam path by direct reflection. Moreover, the rear mirror 30 is rotated by an adjustment angle that is approximately twice the adjustment angle of the second fold mirror 36. These rotations of the rear mirror 30 and second fold mirror 36 suppresses parasitic mode paths that would otherwise exist.

A laser chamber may include a first discharge electrode, a second discharge electrode, a fan making a laser gas flow through a discharge space between the first and second discharge electrodes, a first insulating member disposed on upstream side and downstream side of the first discharge electrode in the laser gas flow, a first metal damper member disposed on upstream side of the second discharge electrode and a second insulating member disposed on downstream side of the second discharge electrode in the laser gas flow, and a second metal damper member disposed on downstream side of the second insulating member in the laser gas flow. In a boundary portion between the second metal damper member and the second insulating member, a first discharge space side surface of the second metal damper member may be located further toward the opposite side to the discharge space than a second discharge space side surface of the second insulating member. A first corner formed by the first surface and a first side surface of the second metal damper member, the first side surface being on the side of the second insulating member, may be in contact with a second side surface of the second insulating member, the second side surface being on the side of the second metal damper member.

Provided is a laser device that includes a laser chamber in which a pair of discharge electrodes are disposed; a line narrowing optical system including a grating disposed in a position outside the laser chamber; a beam expander optical system that increases a diameter of a light beam, outputted from the laser chamber and traveling toward the grating, in a first direction parallel to a discharge direction between the discharge electrodes and in a second direction orthogonal to the discharge direction; and a holding platform that is formed as a component separate from the laser chamber and the grating, holds the beam expander optical system, and forms along with the beam expander optical system a beam expander unit.

A laser apparatus includes an optical element disposed on a laser beam axis, an actuator configured to displace the optical element to displace the laser beam axis, a driving amount monitor configured to monitor a driving amount of the actuator, an optical axis monitor disposed along the laser beam axis and configured to monitor the laser beam axis, and a control unit configured to control the actuator based on a monitoring result of the optical axis monitor and determine abnormality of the optical element based on a monitoring result of the driving amount monitor.

An argon fluoride (ArF) laser system for inertial nuclear fusion energy production with lower required laser energy than other laser drivers. An Argon fluoride laser system uniformly illuminates a spherical capsule comprising an outer ablator wall surrounding an inner shell comprising the fusion fuel. The laser beams are adjusted spectrally to achieve a bandwidth of up to 12 THz and a coherence time as low as 80 femtoseconds that in combination with the short wavelength (193 nm) suppress laser plasma instabilities. Uniform spherical acceleration causes the inner shell of the target capsule to form a spherical assembly of compressed fuel surrounding a hot spot that has sufficient temperature, density and size to ignite and initiate a thermonuclear burn.

A light emitting sealed body includes: a housing which stores a discharge gas and is provided with a first opening to which first light is incident along a first optical axis and a second opening from which second light is emitted along a second optical axis; a first window portion which hermetically seals the first opening; a second window portion which hermetically seals the second opening; and a first electrode and a second electrode. The housing is formed of a light shielding material which does not transmit the first light and the second light. An internal space is defined by the housing, the first window portion, and the second window portion and the internal space is filled with the discharge gas. The first opening and the second opening are disposed so that the first optical axis and the second optical axis intersect each other.

Methods and systems are disclosed for using a chromatic lens system to provide a flying focusi.e., an advanced focusing scheme enabling spatiotemporal control of a focal location. In a method, a photon beam is emitted from a source at a wavelength. The photon beam may have more than one wavelength. The photon beam is focused to a focal location using a chromatic lens system. The focal location is at a first longitudinal distance along an optical axis from the chromatic lens system. The wavelength of the photon beam is changed as a function of time to change the focal location as a function of time. The wavelength may be changed such that the focal location changes with a focal velocity.

In a method, energy is supplied to a first gas discharge chamber of a first stage until a pulsed amplified light beam is output from the first stage and directed toward a second stage. While the energy is supplied to the first gas discharge chamber: a value of an operating parameter of the first gas discharge chamber is measured; it is determined whether to adjust an operating characteristic of the first gas discharge chamber based on the measured value; and, the operating characteristic of the first gas discharge chamber is adjusted if it is determined that the operating characteristic of the first gas discharge chamber should be adjusted. After it is determined that the operating characteristic of the first gas discharge chamber no longer should be adjusted, then an adjustment procedure is applied to an operating characteristic of a second gas discharge chamber of the second stage.

In a method, energy is supplied to a first gas discharge chamber of a first stage until a pulsed amplified light beam is output from the first stage and directed toward a second stage. While the energy is supplied to the first gas discharge chamber: a value of an operating parameter of the first gas discharge chamber is measured; it is determined whether to adjust an operating characteristic of the first gas discharge chamber based on the measured value; and, the operating characteristic of the first gas discharge chamber is adjusted if it is determined that the operating characteristic of the first gas discharge chamber should be adjusted. After it is determined that the operating characteristic of the first gas discharge chamber no longer should be adjusted, then an adjustment procedure is applied to an operating characteristic of a second gas discharge chamber of the second stage.