Abstract: A capsule (20) having a glass wall (21) and containing mercury is positioned in a radiation-transmitting discharge vessel, after which the discharge vessel is provided with a rare gas and closed, means for maintaining an electric discharge are arranged in or adjacent the discharge vessel. The capsule is opened by fusion after the discharge vessel has been closed by heating the capsule by irradiation (42) with a parallel beam of radiation through the wall of the discharge vessel. The wall of the capsule has for this radiation an absorption coefficient which amounts at least ten times that of the wall portion of the discharge vessel.

Abstract: In a method according to the invention, a capsule (20) having a glass wall (21) and containing mercury is positioned in a radiation-transmitting discharge vessel, after which the discharge vessel is provided with a rare gas and closed, means for maintaining an electric discharge are arranged in or adjacent the discharge vessel, and the capsule is opened by fusion after the discharge vessel has been closed in that the capsule is heated by irradiation (42) with a parallel beam of radiation through the wall of the discharge vessel. The wall of the capsule has for this radiation an absorption coefficient which amounts at least ten times that of the wall portion of the discharge vessel. The method according to the invention renders possible a comparatively simple lamp construction.

Abstract: An electrodeless low-pressure discharge lamp is provided with a lamp vessel which is closed in a gastight manner, which surrounds a discharge space, and which contains a filling of mercury and rare gas. The lamp vessel has a cavity and a collar where the cavity is open towards the exterior, an electric coil being accommodated in the cavity and support with an amalgam being arranged in the discharge space. The collar is made of metal and the support of the amalgam is fastened to the collar. This construction counteracts degeneration of the amalgam.

Abstract: A method of manufacturing a low-pressure mercury vapor discharge lamp with a discharge vessel comprising two or more substantially parallel co-extending glass discharge tube portions (4 and 5) interconnected through a coupling which extend transversely to the wall of said tube portions. First, the inner wall of an elongate tube is provided with a luminescent material. Then, while heating at least a short zone of the wall, the elongate tube is then divided into two portions. End walls are formed during the division on which the luminescent layer extends the thickness of the tube wall and the temperature of the heated zone are chosen so that no particles of the luminescent material are enclosed in the glass of the end wall during said dividing process and fracture is avoided at least after cooling.At least at the area of the transition from the end wall to the tube wall, the ratio AB/CD is 0.4 to 0.8.