Abstract: The invention relates to an improved low-pressure gas discharge lamp comprising a gas discharge vessel (1) surrounding a discharge space (2), containing a gas filling, and further comprising means to generate an electromagnetic field (3) and means for generating and maintaining a low-pressure gas discharge. The lamp is characterized in that the discharge lamp is provided with a first phosphor coating on a surface of the gas discharge vessel and with a second phosphor coating, the second phosphor coating being provided on a surface of the lamp that is more remote from the discharge space compared to the first phosphor coating, and the first phosphor coating being selected from the group of thermally stable phosphors. The low-pressure discharge lamp provides increased efficiency and reduced solarisation as compared to commercially available low-pressure discharge lamps.

Abstract: Low-pressure mercury vapor discharge lamp comprises a light-transmitting discharge vessel (10) enclosing, in a gastight manner, a discharge space (13) provided with a filling of mercury and a rare gas. The discharge vessel comprises discharge means (20a; 20b) for maintaining a discharge in the discharge space. The discharge vessel is provided with a container comprising an amalgam (2). The container is provided with releasing means (4) for the controlled release of mercury vapor from the amalgam. The releasing means is open during lamp operation and is substantially closed when, during lamp operation, the temperature of the amalgam becomes higher than a pre-determined temperature. Preferably, the pre-determined temperature corresponds to a temperature of a range of temperatures at which the mercury-vapor pressure above the amalgam is relatively stable.