A lamp made of a tube having a light emission portion glass (1) and a side tube portion glass (2) that extends from the light emission portion glass. The lamp has a sealed electrode assembly having an electrical current supply line (3) with one end portion connected to a metal foil (4). A first portion of the side tube portion where an electrical current supply line is located is heated and this portion is compressed by a first pressure. A second portion of the side tube portion where a metal foil is located is heated and this portion is compressed by a second pressure. The second pressure is made larger than the first pressure. <IMAGE>
