A spiral mercury arc light source of the low pressure variety and 2-kilowatt power dissipation is described. The use of this powerful but geometrically undesirable arrangement for making depolarization measurements is investigated. Calculations of convergence errors using the polarized incident light method of Edsall and Wilson indicate a linear convergence correction of measured ρ-values. Measurement of depolarization values of Raman lines whose ρ-value is accurately known confirms the theoretical calculation of convergence correction. From the results moderately accurate ρ-values can be obtained by this method by using an empirical correction curve.
D. H. RANK and R. E. KAGARISE, "Empirical Convergence Correction of Depolarization Measurements," J. Opt. Soc. Am. 40, 89-91 (1950)