Abstract: A low pressure mercury vapor discharge lamp comprising a fluorescent tube having an amalgam container containing amalgam to control mercury vapor pressure at a steady lighting, a holder holding both ends of the fluorescent tube, a lighting circuit to light the fluorescent tube, a case accommodating the lighting circuit, and a base provided to the case, wherein the amalgam container and the base are connected with each other by a heat conductive component, so that the amalgam temperature is controlled at a proper value and the luminous efficiency is improved.

Abstract: A light-bulb-shaped fluorescent lamp accommodates in an outer housing that includes a transparent globe and a case, a bent fluorescent tube that has a pair of electrodes at both ends and contains an amalgam and a rare gas, and an electronic lighting circuit lighting the fluorescent tube. A light-bulb-shaped fluorescent lamp which has high conformity to regular light bulbs and realizes the same brightness as a regular 60 W light bulb while consuming less power than a conventional light-bulb-shaped fluorescent lamp is provided by setting the external diameter of the globe in the range of 55-65 mm, the total length of the globe in the range of 65-80 mm, the internal diameter of the fluorescent tube in the range of 7-11 mm, and the distance between the electrodes in the range of 200-280 mm.