Light emitting element device, light receiving element device, optical apparatus, fluoride crystal, process for producing fluoride crystal and crucible

摘要

The present invention, calcium fluoride in a vessel with a screen installed to a window pane is formed by a crystal window will have installed a short-wavelength light emitting device such as ultraviolet light-emitting device, blue light emitting device. According to the present invention, the reliability can be obtained a light emission element unit. Fluoride crystal of the present invention containing any one or both of a metal or metal halide. Method of producing a fluoride crystal according to the present invention, in the crucible filling the raw powder in the cavity portion, and a crucible in the method of producing a fluoride crystal by heating in a vertical Bridgeman furnace, the cross-section of the same study of the crucible is, a shortest diameter this will be small. Crucible of the present invention to manufacture, a fluoride crystal, a raw powder charged in the cavity and, in a crucible which is heated in a vertical Bridgeman furnace, the cavity end face, and a smaller minimum diameter. ;