Low-pressure mercury discharge lamp with an external tube

摘要

Low pressure mercury discharge lamp consists of an inner bulb forming a gas discharge vessel having a wall made from a material which is permeable for electromagnetic radiation and coated with a phosphor; an outer bulb surrounding the inner bulb and having a wall containing a UV-A phosphor; and devices for producing and maintaining a low pressure mercury gas discharge. Preferred Features: The wall of the outer bulb has a coating containing the UV-A phosphor, or is made from a material containing a polymeric plastic and the UV-A phosphor. The UV-A phosphor is selected from ZnS:Ag; YVO4:Eu; Y(V, P)O4:Eu; Y2O3:Eu; CaSiO3:Ce,Mn; Y2SiO5:Ce,Mn; BaMgAl10O17: Eu, Mn and (Ba, Sr, Ca)5(PO4)3Cl:Eu,Mn.