ULTRAVIOLET-RAY EMITTING FLUORESCENT LAMP

摘要

PROBLEM TO BE SOLVED: To provide an ultraviolet-ray emitting fluorescent lamp having an enhanced luminous strength of near-ultraviolet rays and suitable for a photocatalyst. SOLUTION: In this lamp, a phosphor layer 2 composed of an europium- activated barium aluminum fluoride (BaAlF5Eu) phosphor emitting light by ultraviolet-ray excitation is formed on the inner wall surface of a light transmissive airtight container composed of a soda glass tube 1 and electrodes 5 and 6, an argon gas and a mercury are sealed inside the glass tube 1. A photocatalyst layer 7 composed of an anatase crystal TiO2 on the outer surface of the glass tube 1. When high frequency voltage is applied to cold cathodes 5 and 6 to generate discharge and an ultraviolet ray of 254 nm is radiated from the mercury, the phosphor layer 2 efficiently emits near-ultraviolet rays. The photocatalyst layer 7 presents photocatalyst effects by the near-ultraviolet rays.