DISCHARGE ELECTRODE FOR ALLOWING FOR HIGH ELECTRICAL CONDUCTIVITY DURING START AND EFFICIENT HEATING AND THERMIONIC EMISSION, DISCHARGE LAMP AND METHOD FOR MANUFACTURING THE DISCHARGE ELECTRODE

摘要

PURPOSE: A discharge electrode, a discharge lamp, and a method for manufacturing the discharge electrode are provided to lengthen the life of the discharge electrode and allow for a high electrical conductivity during start at a room temperature and efficient heating and thermionic emission. CONSTITUTION: A discharge electrode comprises a radiation unit including wide band gap semiconductors(1a,1b) having a band gap of 2.2eV or wider at 300K; and stem leads(21a,22a) serving as a pair of current supply terminals for supplying current to the radiation unit. Acceptor impurity atoms and donor impurity atoms are doped in the band gap semiconductor, and the activation energy of the donor impurity atoms is larger than the activation energy of the acceptor impurity atoms.