gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1966.035.273.10 A Test of the Linearity of a Photomultiplier Used for Reflectivity Measurement Phillips R. Bradshaw P. M. D. Department of Geology, University of Durham 3 1966 35 273 756 758 4 6 1965 Copyright © 1966, The Mineralogical Society 1966 Summary

A test of the linearity of a photomultiplier has been made using crossed polars as an optical attenuator. An expression is derived that allows for the measurable transmission of a polarizing filter in directions other than the permitted vibration direction. The linearity is shown to be adequate for accurate reflectivity measurement.