Containment structure for light source capsules operating at other than the pressure of a surrounding gas

摘要

A high intensity discharge lamp (10) has an envelope (12) having a base end (12a), a middle portion (12b) and domed end (12c) arrayed along an envelope longitudinal axis (14). Two spaced apart electrical lead-ins (34, 36) are sealed in the base end (12a) and extend into the envelope (12). A substantially U-shaped frame (38) is within the envelope (12) and the U-shaped frame comprises glass tubing 26a. A light source (16) has an arc discharge capsule (16b) positioned within the frame (38) and a containment vessel (18) is spaced from and surrounds the arc discharge capsule 16b. The containment vessel (18) comprises a transparent structure (19) attached to the frame (38) and formed to provide multiple, independent, localized fractures capable of absorbing the given kinetic energy possessed by the shards.