METAL HALIDE LAMP

摘要

PROBLEM TO BE SOLVED: To provide a metal halide lamp that substantially does not contain mercury in a discharging space, restraining lowering of lighting voltage at stable lighting, while preventing excessive release of sodium. SOLUTION: Metal halide containing sodium and scandium but not containing mercury, and a rare gas are sealed in a discharging space 111 of a translucent airtight vessel 1 composed of a light-emitting tube part 11 forming the discharging part 111 and sealing parts 121, 122 formed on both sides of the light-emitting tube part 11. Metal foils 21, 22 are sealed in the inside of the sealing parts 121, 122. A pair of electrodes 31, 32 are connected to one end parts thereof, and the other end parts are arranged so as to face each other in the discharging space 11, while keeping a prescribed inter-electrode distance. A translucent outer tube 7, in which one or plurality of metal oxide containing Al2O3by 500 ppm or higher and 2,500 ppm or lower are doped, is mounted on the airtight container 1. COPYRIGHT: (C)2006,JPO&NCIPI