US Patent 7852004 Ignition aid and fitting shroud for discharge lamp

An ignition aid (50, 60, 70, 80, 100, 120, 130, 150, 160, or 170) is provided for an HID lamp (20). Particularly the ignition aid includes an electrically conductive coil or coil portions wrapped around selected portions of the arc tube to act as the ignition aid and lower the breakdown voltage. In other embodiments, starting aids, and particularly one or more turns of the conductive coil or coil portions support the arc tube within an opening of a surrounding shroud (90) and thereby control the spacing between the arc tube (20) and the shroud (90). This limits the maximum thermal stress of the arc tube within a desired range.