Abstract: Techniques are disclosed that allow for the use of metal halide lamps in dimming applications, as well as other discharge lamps susceptible to dimming-induced chromaticity drift. Examination of such lamps reveals that some of the spectral changes that cause chromaticity drift during dimming are localized in narrow band regions of the spectrum, and lamp emission in these regions is enhanced (either increased or decreased) relative to the rest of the spectrum. Selective filtering of the enhanced emission caused by dimming can be used to reduce chromaticity shift. For instance, a filter deposited on and/or integrated into a lamp component (such as the arc tube, shroud, and/or outer jacket) operates to block transmission of those regions of the spectrum.

Abstract: An inductively coupled fluorescent discharge lamp includes a light transmissive envelope having a re-entrant cavity that has an outer surface inside the envelope, and an excitation coil inside the re-entrant cavity, and a spring clip that is attached to the outer surface of the re-entrant cavity by spring action of the spring clip on the outer surface, where the spring clip includes an amalgam. The spring clip may include a layer of the amalgam plated on a surface of the clip, or an amalgam-bearing flag attached to the clip.