MERCURY-FREE ARC TUBE FOR DISCHARGE LAMP UNIT

摘要

A mercury-free arc tube for discharge lamp device is provided to obtain the same amount of luminous output using the metal halide for shock-absorbing as the buffer material or the luminescent material instead of mercury. A mercury-free arc tube for discharge lamp device comprises a plurality of electrodes(15a,15b) and a closed chamber(12). The metal halide for the main part radiation and the inert gas are sealed inside the closed chamber. The cleanliness indicator(P^2ÀW/rho) including the envelope density(rho) of the metal halide, the charged pressure(P) of the inert gas, and the maximum committed electric power(W) is more than 800. The metal halide for shock-absorbing is sealed besides the metal halide for the main part radiation within the closed chamber.