Target for ultraviolet light generation, electron beam-excited ultraviolet light source, and production method for target for ultraviolet light generation

#One aspect of the present invention relates to a target for ultraviolet light generation, an electron-beam-excited ultraviolet light source, and a method for manufacturing a target for ultraviolet light generation.

#Patent Literature 1 describes the use of a single crystal containing praseodymium (Pr) as a material for a scintillator employed in PET devices. Patent Literature 2 discloses a technique concerning an illumination system in which a wavelength of light emitted from a light-emitting diode is converted by a phosphor so as to attain white light.

#Patent Literature 1: International Publication No. 2006/049284 pamphlet

#FIG. 1 is a schematic view illustrating an inner structure of the electron-beam-excited ultraviolet light source in accordance with an embodiment;

#FIG. 2 is a side view illustrating a structure of a target for ultraviolet light generation;

#FIG. 3 is a graph illustrating a spectrum of ultraviolet light obtained by irradiating with an electron beam the target for ultraviolet light generation made by a first example;

#In the following, embodiments of the target for ultraviolet light generation, electron-beam-excited ultraviolet light source, and method for manufacturing a target for ultraviolet light generation in accordance with one aspect of the present invention will be explained in detail with reference to the drawings. In the explanation of the drawings, the same constituents will be referred to with the same signs while omitting their overlapping descriptions.

#FIG. 1 is a schematic view illustrating an inner structure of an electron-beam-excited ultraviolet light source 10 in accordance with an embodiment. In this electron-beam-excited ultraviolet light source 10, as illustrated in FIG. 1, an electron source 12 and an extraction electrode 13 are arranged on the upper end side within a glass envelope (electron tube) 11 evacuated under vacuum. When an appropriate extraction voltage is applied between the electron source 12 and extraction electrode 13 from a power supply part 16, an electron beam EB accelerated by a high voltage is emitted from the electron source 12. As the electron source 12, one emitting an electron beam having a large area (e.g., cold cathodes such as carbon nanotubes or hot cathodes) can be used.

#A target 20 for ultraviolet light generation is arranged on the lower end side within the envelope 11. The target 20 is set to the ground potential, for example, while a high negative voltage is applied from the power supply part 16 to the electron source 12. As a consequence, the target 20 is irradiated with the electron beam EB emitted from the electron source 12. The target 20 is excited in response to the electron beam EB and generates ultraviolet light UV.