title: Note: simple means for selective removal of the 365 nm line from the Hg spectrum using Dy.
abstract: The emission spectrum of mercury has a notable line at about 365 nm under both low and medium-high pressure conditions. A simple filter based on a solution of dysprosium ions, Dy(3+), is shown to be very useful for applications of Hg-light sources where this line is unwanted. The presented filter is cheap, robust, and stable towards degradation or bleaching - even under intense irradiation. The absorption spectrum for the Dy-filter is presented along with emission spectra from both low-pressure and high-pressure Hg-lamps to illustrate the utility of the technique under best-case and worst-case conditions. Attenuation of the 365 nm spectral line is almost total for the low-pressure source whereas for the high-pressure source the attenuation is about a factor of three.
authors.affiliation: Department of Physics, CINF, Technical University of Denmark (DTU), Building 312, Fysikvej, DK-2800 Kgs. Lyngby, Denmark. Peter.Vesborg@fysik.dtu.dk
authors.forename: P C K
authors.initials: PC
authors.lastname: Vesborg
authors.forename: I
authors.initials: I
authors.lastname: Chorkendorff
authors.forename: T
authors.initials: T
authors.lastname: Brock-Nannestad
authors.forename: J R
authors.initials: JR
authors.lastname: Dethlefsen
authors.forename: J
authors.initials: J
authors.lastname: Bendix