A light source having a substantially elliptical cross-section for UV curing lamp assemblies is disclosed. The light source has a pair of end sections and a central section of smaller diameter than the end sections. The end sections are each connected to the central section by a tapered section the diameter of each of which decreases from an end that mates with an end section toward an end that mates with the central section. Each of the end sections has a substantially elliptical cross-section. The central section and the tapered sections may have a substantially elliptical cross-section. The aspect ratio of the elliptical cross-section of the end sections and the central section of the light source is preferably about 2:1.