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A new versatile pulsed light-emitting-diode system capable of producing time-resolved luminescence spectra is described. The light-emitting diodes are pulsed by signals from a multivibrator with pulse widths ranging from 25 ns (FWHM) to 30 µs. Time-resolved luminescence spectra from feldspars and quartz, materials relevant to luminescence dating, have been recorded. Examples of time-resolved spectra and the lifetimes deduced from them are given.

This is the second in a set of paired papers on the analysis of time-resolved optically stimulated luminescence. This paper compares experimental results and computer simulations with corresponding conceptual models discussed in the first of this set of papers. The evaluation of principal and subsidiary luminescence lifetimes from time-resolved luminescence spectra measured during or after pulsed optical stimulation is illustrated using suitable analogues of exponential functions developed in the preceding paper. Various methods for calculating the activation energies for thermal quenching, thermal assistance and the frequency factor for the thermal quenching process using the temperature dependence of both luminescence lifetimes and luminescence intensity are described, as are techniques for dealing with cases not easily described by the standard Mott–Seitz model of luminescence. The paper then compares continuous and time-resolved optical stimulation methods, where it is shown that, dependent on suitable selection of the pulse-width, stimulation and measurement time, pulsing the stimulation light might give better accuracy in the determination of the luminescence.

This is the first of two linked papers on the analysis of time-resolved optically stimulated luminescence. This paper focusses on a theoretical basis of analytical methods and on methods for interpretation of time-resolved luminescence spectra and calculation of luminescence throughput. Using a comparative analysis of the principal features of time-resolved luminescence and relevant analogues from steady state optical stimulation, formulae for configuring a measurement system for optimum performance are presented. We also examine the possible use of stretched-exponential functions for analysis of time-resolved optically stimulated luminescence spectra.

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