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.

An excimer bulb assembly, with an excimer bulb, at least one integral captured reflector, and an integral filter such that the excimer bulb only emits substantial UV radiation between 200 nm and 230 nm, using a filter that passes light from about 200 nm to 234 nm (+/−2 nm).

An excimer bulb fixture including an excimer bulb emitting a beam of UV light at a far UV C wavelength. The fixture includes a krypton/chloride bulb, a band pass filter and a diffusion layer or lens. The krypton/chloride bulb is adapted to project a beam of far UV C light through the filter and then through the diffusion layer or lens. The band pass filter is adapted to block substantial UV radiation wavelengths longer than 234 nm. The diffusion layer or lens is adapted to widen the beam of far UV C light. A method far widening a beam of far UV C light includes the steps of projecting a beam of far UV C light produced by a krypton/chloride bulb through a band pass filter; blocking substantially UV C radiation longer than 234 nm; projecting the filtered beam through a diffusion filter or lens; and, widening the filtered beam.

Provided is an ultraviolet light irradiation device that is capable of causing effective inactivation of microorganisms as well as a method of using the ultraviolet light irradiation device.

An ultraviolet light irradiation device includes a light source that radiates ultraviolet light with a wavelength in a range of 190 nm to 235 nm; a housing that houses the light source; an extracting portion that extracts the ultraviolet light that is radiated from the light source and causes it to be directed toward an exterior of the housing; and a diffusing member that diffuses the ultraviolet light.

The light source contains a chamber with a region of radiating plasma sustained by a focused beam of a CW laser. The chamber consists of a tube, a bottom and a cap. The cap is arranged for filling the chamber with gas. The tube and bottom are made from an optically transparent material. The bottom is arranged for input into the chamber of the CW laser beam and pulsed laser beams used for the plasma ignition, while the tube is arranged for exit of the output beam of plasma radiation. Preferably shape of the tube is arranged for reducing aberrations which distort a path of rays of plasma radiation passing through the tube wall. The technical result consists in creating electrodeless high-brightness broadband light sources with the high spatial and power stability, and in providing an ability to collect plasma radiation in a spatial angle of more than 9 sr.

A lighting element with a gaseous tritium light source and an elongated plastic housing that at least partially encloses the gaseous tritium light source with its housing shell and forms a latching element that snaps together with the gaseous tritium light source, which can be inserted into the plastic housing, and holds it in the plastic housing. A rugged lighting element can be produced if the latching element is formed by at least one catch element, which catch element has a radially sprung flexible spring and at least one, preferably two, inwardly oriented snaps with an indentation for snapping together with the gaseous tritium light source.

A laser-sustained broadband light source includes a gas containment structure and multiple jet nozzles. The jet nozzles are configured to direct multiple liquid jets of plasma-forming material in directions to collide with one another within the gas containment structure. The laser-sustained broadband light source further includes a laser pump source configured to generate an optical pump to sustain a plasma in a region of the gas containment structure at a collision point of the plurality of liquid jets and a light collector element configured to collect broadband light emitted from the plasma.

An excimer bulb assembly, with an excimer bulb, at least one integral captured reflector, and an integral filter such that the excimer bulb only emits substantial UV radiation between 200 nm and 230 nm, using a filter that passes light from about 200 nm to 234 nm (+/−2 nm).

An excimer bulb assembly, with an excimer bulb, at least one integral captured reflector, and an integral filter such that the excimer bulb only emits substantial UV radiation between 200 nm and 230 nm, using a filter that passes light from about 200 nm to 234 nm (+/−2 nm).

An excimer lamp includes light-emitting gases containing krypton gas and chlorine gas in a sealing body composed of fused quartz glass having an absorption band at least in a wavelength band of 240 nm to 260 nm. An ultraviolet light irradiation device includes: an excimer lamp having light-emitting gases containing krypton gas and chlorine gas in a sealing body; a housing having an extraction part for extracting ultraviolet light emitted from an excimer lamp; and fused quartz glass disposed in the extraction part and having an absorption band at least in a wavelength band of 240 nm to 260 nm.