Abstract: A discharge lamp has an axis with an arc tube having a hollow body containing an axially aligned arc generating and sustaining medium. The lamp electrodes and hollow body are arrayed along the axis. A sealed shroud surrounds the arc tube. The shroud and arc tube form an arc tube assembly. An envelope surrounds the arc tube assembly, and includes a base portion with a cylindrical part. Electrical lead-ins extend through the base portion and mechanically and electrically connect to the electrodes. A strengthening member for preventing the arc tube assembly from axial displacement as a result of forces applied substantially normal to the axis is provided. The strengthening member comprises an elongated element having first and second ends. The first end is formed to substantially engage the arc tube assembly, near an upper end, and the second end is formed to substantially engage the base portion.

Abstract: A discharge lamp has an axis with an arc tube having a hollow body containing an axially aligned arc generating and sustaining medium. The lamp electrodes and hollow body are arrayed along the axis. A sealed shroud surrounds the arc tube. The shroud and arc tube form an arc tube assembly. An envelope surrounds the arc tube assembly, and includes a base portion with a cylindrical part. Electrical lead-ins extend through the base portion and mechanically and electrically connect to the electrodes. A strengthening member for preventing the arc tube assembly from axial displacement as a result of forces applied substantially normal to the axis is provided. The strengthening member comprises an elongated element having first and second ends. The first end is formed to substantially engage the arc tube assembly, near an upper end, and the second end is formed to substantially engage the base portion.