Low-pressure mercury vapour discharge lamp

A low-pressure mercury vapour discharge lamp according to the invention comprises a radiation-transmitting, glass discharge vessel which encloses a discharge space in a gastight manner and which is provided with a filling of mercury and a rare gas. The lamp in addition comprises means for maintaining an electrical discharge in the discharge space. An intermediate layer which repels alkali metals and which is made of, for example, silicon oxide lies on a surface of the discharge vessel facing towards the discharge space, which intermediate layer supports a protective layer of at least an oxide of at least one element from the series formed by magnesium, aluminium, titanium, zirconium, and the rare earths, this protective layer being substantially free from particles greater than 1 mu m. The lamp according to the invention has a comparatively low mercury consumption.\!