Laser driven sealed beam lamp with improved stability

A sealed high intensity illumination emitting device configured to receive a laser beam from a laser light source, the device comprising:

• a sealed cylindrical chamber configured to contain an ionizable medium, the chamber comprising and bounded by a cylindrical wall with an inner diameter, an ingress window transparent to a first wavelength range and an egress window disposed opposite the ingress window transparent to a second wavelength range;
• a tube insert disposed within the chamber formed of an insulating material comprising a walled region separating an insert interior portion from an insert exterior portion, an ingress end abutting the chamber ingress window, and an egress end abutting the chamber egress window,
• wherein the insert is configured to receive the laser beam within the insert inner diameter.