An ultraviolet light emitting phosphor for mercury-free lamps is a phosphor composed of a phosphate containing at least two metal elements selected from the group consisting of group 13 elements and lanthanoid series elements, and is excited to emit ultraviolet by irradiation with vacuum ultraviolet rays or an electron beam.

A lighting device is presented. The lighting device includes an LED light source; and a red/far-red emitting phosphor radiationally coupled to the LED light source, wherein the red/far-red emitting phosphor comprises a host material activated with an activator ion, and wherein the activator ion comprises at least one of Sm.sup.2+ and Mn.sup.2+. Numerous other aspects are provided.

A lighting device is presented. The lighting device includes an LED light source; and a red/far-red emitting phosphor radiationally coupled to the LED light source, wherein the red/far-red emitting phosphor comprises a host material activated with an activator ion, and wherein the activator ion comprises at least one of Sm.sup.2+ and Mn.sup.2+. Numerous other aspects are provided.

An excimer lamp is such that that an interior of a discharge vessel is filled with a first gas including krypton (Kr) or xenon (Xe); a second gas including chlorine (Cl) or bromine (Br); and a third gas which is at least one species selected from among the group consisting of argon (Ar), neon (Ne), and helium (He), and which exhibits a partial pressure P.sub.b that is not less than a partial pressure P.sub.lg of the first gas.

An excimer lamp is such that that an interior of a discharge vessel is filled with a first gas including krypton (Kr) or xenon (Xe); a second gas including chlorine (Cl) or bromine (Br); and a third gas which is at least one species selected from among the group consisting of argon (Ar), neon (Ne), and helium (He), and which exhibits a partial pressure P.sub.b that is not less than a partial pressure P.sub.lg of the first gas.

The present invention provides a deep ultraviolet radiation apparatus that is safe and has a high bacteria eliminating effect.

The ultraviolet radiation apparatus comprises an optical filter that prevents the transmission of ultraviolet light of 240 nm or more emitted from a phosphor, wherein the optical filter is arranged facing light emitting surfaces of a gas-discharging tube array-type surface-emitting ultraviolet light source device comprising phosphor layer having a broad emission spectrum with a wavelength width of at least 210 nm to 250 nm with a peak wavelength of 228 nm. Light irradiated from the light source device is incident on a filter membrane with an incident angle thereof being altered by a transparent substrate of the optical filter. An ozone generation space may be formed between the surface-emitting ultraviolet light source device and the optical filter.

A UV emitting device having at least one first phosphor that absorbs UV radiation of a wavelength shorter than 200 nm and at least one second phosphor which absorbs UV radiation of a wavelength between 220 nm and 245 nm. The at least one first phosphor emits UV radiation of a wavelength between 220 nm and 245 nm and the at least one second phosphor emits UV radiation of a wavelength between 250 nm and 315 nm. The at least one first phosphor and the at least one second phosphor are disposed in the form of layers, wherein the at least one first phosphor layer is positioned between a discharge volume and the at least one second phosphor layer.

A UV excitation light source comprises a phosphor. The phosphor contains Sc.sub.xY.sub.1-xPO.sub.4 crystals (wherein 0<x<1), and, upon receiving UV light of a first wavelength, generates UV light of a second wavelength that is longer than the first wavelength. A method for producing the phosphor includes: a first step for producing a mixture that includes an oxide of Y, an oxide of Sc, phosphoric acid, and a liquid; a second step for vaporizing the liquid; and a third step for baking the mixture.

A UV excitation light source comprises a phosphor. The phosphor contains Sc.sub.xY.sub.1-xPO.sub.4 crystals (wherein 0<x<1), and, upon receiving UV light of a first wavelength, generates UV light of a second wavelength that is longer than the first wavelength. A method for producing the phosphor includes: a first step for producing a mixture that includes an oxide of Y, an oxide of Sc, phosphoric acid, and a liquid; a second step for vaporizing the liquid; and a third step for baking the mixture.

The invention relates to a phosphor for a UV emitting device, having the formula Na.sub.1+xCa.sub.1−2xPO.sub.4:PR3.sup.+.sub.x wherein 0<x<0.5.