Patent ID: 7176606

Claim:
A lamp comprising: a transparent envelope having a first region symmetric about an axis, defining an enclosed interior volume, and a second region constructed as a closure region and located adjacent said first region, a light source located in said interior volume and electrically coupled to the exterior through said closure region, an interference filter coating formed on the exterior of said first region, said interference filter coating defining a spectral region of transparency, a light absorbing coating formed on the exterior of said first region, wherein said light absorbing coating comprises a ring-shaped portion encircling a portion of the first region adjacent the closure region, said ring-shaped portion having a thickness in the range of 50 to 200 nanometers, a width in the range of 5 to 20 millimeters, and being located at a distance in the range of 0 to 10 millimeters from said closure region.