Abstract

We have performed an experiment to test our understanding of the run time, T, necessary to achieve a specified precision in the value of the intensity coherence time, τ_c, extracted from correlation functions taken in the strong signal limit, and to test predictions for the values of some experimental parameters that optimize the precision. Using ensembles of 10 correlation functions taken at 5 different choices of sample time, we found that the ensemble estimators for the error in τ_c were well described by the expression $\delta \tau /{\tau }_c=4.2/\sqrt{T/{\tau }_c}$, in agreement with the work of Degiorgio and Lastovka (1971). The sample times used were chosen so that the number of coherence times spanned by the 128 channels of the correlator, α, covered the range 1 ≤ α ≤ 16; in this range, we found no evidence of a minimum in δτ/τ_c to suggest an optimum value of α. These results were independent of whether we used three-parameter or two-parameter least-squares fits to extract τ_c. However, we did find that the two fits gave systematically different values of τ_c, and both show a similar dependence on α.

© 1988 Optical Society of America