Abstract: A light-transmissive discharge vessel (1) encloses a discharge space (10) which contains an ionizable filling comprising an evaporable component. The low-pressure discharge lamp is also provided with coil for maintaining an electric discharge in the discharge space, and with a carrier (3) with a resilient body (30) and an open holder (31). The resilient body (30) is clamped inside a tube (14) which communicates with the discharge space (10). The holder (31) is clamped inside the resilient body (30). In the absence of the holder (31), the resilient body (30) can be inserted in a released state in the tube (14) with play (x).

Abstract: A lighting unit comprises an electrodeless low-pressure discharge lamp (10) and an electric supply (60) for the lamp. The lamp is provided with a discharge vessel (20) having a radiation-transmitting enveloping portion (21) and a recessed portion (24). The discharge vessel encloses a discharge space (27) in a gastight manner and contains an ionizable filling. The lamp also is provided with a coil (30) positioned in the recessed portion for generating a high-frequency magnetic field so as to maintain an electric discharge in the discharge space. The enveloping portion (21) of the discharge vessel is provided with a radiation-transmitting, electrically conducting layer (22) at a surface facing the discharge space (27). This layer is electrically connected to a lead-through member (42) which issues to the exterior of the discharge vessel. The lead-through member is a metal tube which forms at least a portion of a tubular projection (46, 42, 47).

Abstract: The invention relates to a high-pressure sodium discharge lamp provided with a discharge vessel (3) with a ceramic wall (3a) of aluminum oxide in which at least Na as an ionizable filling component, a rare gas and Al (20) are present. According to the invention, the Al is provided near the wall of the discharge vessel in a location which reaches a temperature of at least 1000 K in the operational condition of the lamp.

Abstract: A low-pressure mercury vapor discharge lamp comprising a glass discharge envelope (1) in which during operation of the lamp a discharge is present and which contains mercury and a rare gas, at least a part of the inner wall of the discharge envelope being provided with a thin at least substantially homogeneous continuous transparent layer (4) which is resistent to the action of the discharge.According to the invention, this transparent layer (4) contains an oxide of at least one of the groups comprising yttrium, scandium, lanthanum, gadolinium, ytterbium and lutetium.

Abstract: Luminescent bivalent europium-activated barium borophosphates having defined compositions by the formula Ba.sub.3-p Eu.sub.p BP.sub.3 O.sub.12, where 0.01.ltoreq.p.ltoreq.0.50. A quantity of not more than 20 mole % of the Ba may be replaced by Sr and/or Ca. The borophosphate can be used in luminescent screens of low-pressure mercury vapour discharge lamps.

Abstract: A luminescent material having the eulytine crystal structure and a composition defined by Ca.sub.3-x-y-p Me.sub.x Sn.sub.p Ln.sub.1+y-q-r A.sub.q Sb.sub.r (PO.sub.4).sub.3-y (SiO.sub.4).sub.y, wherein Me is Sr and/or Ba, Ln is Y, La, Gd and/or Lu, and A is Ce and/or Tb and wherein 0.ltoreq.x.ltoreq.2.5, 0.ltoreq.y.ltoreq.0.5, 0.ltoreq.P.ltoreq.0.2, x+y+p.ltoreq.2.5, 0.ltoreq.q.ltoreq.1+y-r, 0.ltoreq.r.ltoreq.0.5, p+q+r.noteq.0.