Low-pressure gas discharge lamp with a reduced argon proportion in the gas filling
View Patent ↗The invention relates to novel gas fillings of low-pressure gas discharge lamps for reducing the starting and arc drop voltages at low Hg vapor pressures. In favor of a mixture consisting of Ne and Kr, the Ar portion of the gas filling is considerably reduced.
1. A low-pressure gas discharge lamp having a discharge vessel and a gas fill in the discharge vessel wherein the gas fill consists of:
46% by volume to 60% by volume Ne,
5% by volume to 15% by volume Ar,
up to 2% by volume further noble gases and standard impurities, and remainder Kr.
2. The lamp as claimed in claim 1 , in which the lower limit for the Ne content in the gas fill is 48% by volume, and the upper limit is 57% by volume.
3. The lamp as claimed in claim 1 , having a Hg amalgam as the Hg source which regulates the vapor pressure, which lamp is designed in such a way that the Hg amalgam in normal operation reaches a temperature of 100° C. to 170° C.
4. The lamp as claimed in claim 1 , having a discharge tube ( 2 ) which is at least partially wound helically around a free axial space, and having a tube piece which is attached to the discharge tube, the tube piece being attached to the discharge tube at one end of the helix shape and from there extending substantially axially parallel inside the helix shape, and the tube piece containing at least one Hg source and the Hg source being arranged inside the helix shape.
5. The lamp as claimed in claim 1 , which is configured as a linear lamp with an elongate discharge vessel.
6. The lamp as claimed in claim 5 , in which the discharge vessel has a tube diameter of at most 16 mm.
7. The lamp as claimed in claim 3 , in which the Hg amalgam is formed from a Hg fraction and a masteralloy, the masteralloy corresponding to the general formula
In a-e X b Y c Z d R e where:
X is at least one element selected from the group consisting of Ag, Cu, Sn,
Y is at least one element selected from the group consisting of Pb, Zn,
Z is at least one element selected from the group consisting of Ni, Te,
R comprises additions of Bi, Sb, Ga and standard residues, and where the following values apply to a, b, c, d, e: 70%≦a≦98%, b≦25%, c≦25%, d≦20%, e≦15%, and
wherein it is furthermore the case that 2%≦b, if c=0%, 5%≦b, if X is Cu, d≦5%, if Z is Ni, and e≦55%, if R is Ga.