US Patent 7215081 HID lamp having material free dosing tube seal

A hermetically sealed lamp having at least one seal-material-free bond. The seal material-free bond may be a material diffusion bond, a mechanically deformed bond such as a cold weld or crimp, a focused heat bond such as a laser bond, or any other such bond. For example, the hermetically sealed lamp may have one or more endcaps diffusion bonded to an arc envelope, such as a ceramic tube or bulb. The hermetically sealed lamp also may have one or more tubular structures, such as dosing tubes, which are mechanically closed via cold welding or crimping. Localized heating, such as the heat provided by an intense laser, also may be used to enhance any of the foregoing bonds.