Abstract: A tubular discharge vessel for a compact low pressure discharge lamp, espally a compact fluorescent lamp, is formed by heating and bending a straight glass tube into a U-shape with a plurality of straight sections and a 180.degree.-bend. Adequate vessel wall thickness is assured at the tubular sections where the bends are formed, by first heating a central section, moving sections lateral to the central section axially toward one another, thereby compressing the heated central section and thickening its walls, and bending or rotating the lateral sections into a parallel orientation. This prevents the bending process from unduly thinning the vessel walls, leading to breakage or rupture under internal gas pressure.

Abstract: A single-ended low-pressure discharge lamp, such as a fluorescent lamp, is ade by providing an inner glass base structure which has a depending portion (2) extending towards the base (14) of the lamp, and an upper flange or rim portion (3) to which the bulb (10) is melted-on as a last step. Two U-shaped tubes (5, 5') are melted-in into an oval deformed region of the depending projecting end portion (2), a pre-heatable electrode (12, 12') being also located within the end region (8, 8a) of the U-shaped tubes, so that, in one working step, after deformation of the glass U-shaped tubes and the glass inner base structure, a press operation will seal together the electrodes within the ends of the U-shaped tubes, the glass of the U-shaped tubes and the inner base structure.

Abstract: Two U-shaped inner tubes, each of which have a straight leg which is hermcally sealed about a preheatable electrode, are sealed into the upper, oval reception section of a preshaped flare. The seal also includes the exhaust tube and the lead-in wire pairs supporting the preheatable electrodes and is carried out as a press seal in one single working step. The other legs of the U-shaped inner tubes remain open. The lower, outwardly facing rim of the preshaped flare which is concentric with the longitudinal lamp axis is sealed to an outer envelope whose neck drops off during this sealing process and which surrounds the U-shaped inner tubes and contains a gas and/or metal vapor filling. The inner tubes are preferably coated with a three-line phosphor, and the outer envelope is provided with a light diffusing coating.