A radiation driven light source comprises laser and focusing optics. These produce a beam of radiation focused on a plasma forming zone within a first container containing a gas (e.g. Xe). Collection optics collects photons emitted by a plasma maintained by the laser radiation to form a beam of output radiation. First container is enclosed within a hermetically sealed second container. Any ozone generated within the second container as a result of ultraviolet components of the output radiation is completely contained within the second container. Second container further filters out the ultraviolet components. Microwave radiation may be used instead of laser radiation to form the plasma.

Materials and optical components formed thereof that are suitable for use in a lighting apparatus to impart a color filtering effect to visible light. At least a portion of such an optical component is formed of a composite material comprising a polymeric matrix material and an inorganic particulate material that contributes a color filtering effect to visible light passing through the composite material, and the particulate material comprises a neodymium compound containing Nd.sup.3+ ions.

A device for emitting ultraviolet light includes at least one excimer lamp and a housing for the excimer lamp(s). Each excimer lamp has a discharge vessel filled with light-emitting gases, and a pair of first and second electrodes that are placed in contact with the discharge vessel and produce a dielectric barrier discharge inside the discharge vessel. The housing is made of an insulating and heat-resistant resin material. The housing is configured to house the excimer lamp(s), and has a light-emitting window that allows light with a center wavelength in a range from 200 nm to 230 nm emitted from the excimer lamp(s) to exit from the housing.

A device for emitting ultraviolet light includes at least one excimer lamp and a housing for the excimer lamp(s). Each excimer lamp has a discharge vessel filled with light-emitting gases, and a pair of first and second electrodes that are placed in contact with the discharge vessel and produce a dielectric barrier discharge inside the discharge vessel. The housing is made of an insulating and heat-resistant resin material. The housing is configured to house the excimer lamp(s), and has a light-emitting window that allows light with a center wavelength in a range from 200 nm to 230 nm emitted from the excimer lamp(s) to exit from the housing.

Modules, systems and methods that disinfect surfaces using ultraviolet (UV) light are disclosed. In one aspect, a UV light-emitting module comprises an enclosure comprising a rear wall and a face plate spaced from the rear wall and comprising a light-transmitting aperture. At least one sidewall extends between the rear wall and the face plate, and at least one UV light emitter is within the enclosure. A ventilation opening is located in one or more walls selected from (1) the rear wall and (2) the at least one sidewall.

Modules, systems and methods that disinfect surfaces using ultraviolet (UV) light are disclosed. In one aspect, a UV light-emitting module comprises an enclosure comprising a rear wall and a face plate spaced from the rear wall and comprising a light-transmitting aperture. At least one sidewall extends between the rear wall and the face plate, and at least one UV light emitter is within the enclosure. A ventilation opening is located in one or more walls selected from (1) the rear wall and (2) the at least one sidewall.

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 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.

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.