Methods and systems for sterilizing a room are disclosed, including using a laser positioned within a housing to generate a pulsed laser beam; and intercepting the pulsed laser beam with a scattering optical element to substantially isotropically scatter the radiation of the pulsed laser beam outside the housing to sterilize the room. The scattering optical element comprises a hollow fused silica bulb filled with solid fused silica spheres or a fiber optic bundle and in some embodiments the scattering optical element is rotated. The pulsed laser beam comprises a wavelength ranging between about 200 nm to about 320 nm and in some embodiments comprises nanosecond or picosecond light pulses. Other embodiments are described and claimed.

A discharge chamber for a deep ultraviolet (DUV) light source includes a housing; and a first electrode and a second electrode in the housing, the first electrode and the second electrode being separated from each other to form a discharge region between the first electrode and the second electrode, the discharge region being configured to receive a gain medium including at least one noble gas and a halogen gas. At least one of the first electrode and the second electrode includes a metal alloy including more than 33% and less than 50% zinc by weight.

An apparatus includes a gas discharge system including a gas discharge chamber and configured to produce a light beam; and a spectral feature adjuster in optical communication with a pre-cursor light beam generated by the gas discharge chamber. The spectral feature adjuster includes: a body defining an interior that is held at a pressure below atmospheric pressure; at least one optical pathway defined between the gas discharge chamber and the interior of the body, the optical pathway being transparent to the pre-cursor light beam; and a set of optical elements within the interior, the optical elements configured to interact with the pre-cursor light beam.

A copper electrode material comprising Cu and unavoidable impurities, wherein the content of the unavoidable impurities is 1 ppm by mass or less and the average crystal grain diameter is 100 μm or less. A copper-containing electrode material having improved corrosion resistance is provided by the copper electrode material.

A set of optical elements for optical extraction composed of packed expanding optical cross sections to efficiently extract from a large gain region. The elements are rectangular shaped concave small expansion lenses matched to rectangular convex collimating lenses. Absorbing sheets divide an overall large volume up into smaller volumes to minimize losses due to amplified spontaneous emission. This arrangement has various applications, particularly in inertial confinement technology, where it may be used to extract energy from KrF laser media energized by electron beams. For certain applications, this regime of the gain medium may have zones at the absorbing sheets where this is no gain.

A discharge chamber for a deep ultraviolet (DUV) light source includes a housing; and a first electrode and a second electrode in the housing, the first electrode and the second electrode being separated from each other to form a discharge region between the first electrode and the second electrode, the discharge region being configured to receive a gain medium including at least one noble gas and a halogen gas. At least one of the first electrode and the second electrode includes a metal alloy including more than 33% and less than 50% zinc by weight.

An optical isolator according to an aspect of the present disclosure includes a first polarizer through which incident light transmits, a Faraday rotator configured to rotate the polarization direction of the light, and a second polarizer through which the light transmits. The Faraday rotator includes a calcium fluoride crystal. When a, b, and c axes are the [001], [100], and [010] crystallographic axes, respectively, and x, y, and z axes are obtained by rotating the three axes by a first angle of 40° to 50° about the c axis and by a second angle of 45° to 75° about the b axis rotated by the first angle, the z axis is parallel to the propagation direction of the light, and the calcium fluoride crystal is disposed such that the transmission axis of the first polarizer and the x axis have an angle difference of 0° to 45°.

An ultraviolet laser apparatus includes an oscillation-stage laser, an amplifier that amplifies the pulse laser light, and an optical isolator. The optical isolator includes a first Faraday rotator that rotates the polarization direction of the pulse laser light output from the oscillation-stage laser by a first angle in a first rotation direction, a first polarizer so disposed to transmit the pulse laser light that exits out of the first Faraday rotator at normalized transmittance greater than or equal to 0.9, a second Faraday rotator that rotates the polarization direction of the pulse laser light passing through the first polarizer by a second angle in the opposite direction to the first rotation direction, and a second polarizer so disposed to transmit the pulse laser light that exits out of the second Faraday rotator at the normalized transmittance greater than or equal to 0.9.

An optical isolator includes a first polarizer arranged such that a transmission axis thereof is set to cause a normalized transmittance with respect to incident light having a wavelength of ultraviolet and linear polarization to be 0.9 or more, a Faraday rotator using a Faraday material configured to rotate a polarization direction of light having transmitted through the first polarizer in a first rotation direction by a first rotation amount by a magnetic field and rotate the polarization direction in a second rotation direction opposite to the first rotation direction by a second rotation amount by optical activity or birefringence, and a second polarizer arranged such that a transmission axis thereof is set to cause a normalized transmittance with respect to the incident light having transmitted through the Faraday rotator to be 0.9 or more.

A laser gas regenerating apparatus regenerates a discharged gas discharged from at least one ArF excimer laser apparatus and supplies the regenerated gas to the at least one ArF excimer laser apparatus connected to a first laser gas supply source that supplies a first laser gas and to a second laser gas supply source that supplies a second laser gas. The laser gas regenerating apparatus includes a data obtaining unit that obtains data on a supply amount of the second laser gas supplied to the at least one ArF excimer laser apparatus; a xenon adding unit that adds, to the regenerated gas, a third laser gas; and a control unit that controls, based on the supply amount, an addition amount of the third laser gas by the xenon adding unit.