Patent ID: 7997747

Claim:
A discharge tube comprising: a glass tube; an outer lead arranged to project from an end portion of said glass tube and be capable of receiving power supply from a power source; and a ferrule having a body mounted to an outer circumference of said glass tube and a conductive part extending from said body, wherein said body has a contact portion to be electrically connected to said power source and is to be borne by a bearing device, while said conductive part is connected to said outer lead, wherein: said glass tube has a substantially cylindrical shape; said body has a cylindrical shape substantially concentric with said glass tube; said body has a plurality of elastic gripping parts circumferentially spaced apart, said plurality of elastic gripping parts being capable of contact with the outer circumference of said glass tube; and a gap is formed between the outer circumference of said glass tube and an inner circumference of said body so as to extend over a substantially entire circumference.