SINTERED POLYCRYSTALLINE ALUMINA

摘要

Increased optical transmission is provided for a body of light transmissive polycrystalline alumina having relatively uniform size equiaxed grains of alumina and which is essentially free of porosity and secondary phase material. A tube of the improved optical material can be used as the light transmissive envelope for high intensity discharge lamps especially sodium and other metal vapor lamps exhibiting increased light output as a result of said improved optical transmission. A method of producing the improved optical material is also disclosed.