In this paper, experimental studies on estimation of absolute groove density of gratings and intergrating groove density errors are reported with typical detector limited accuracies of ±0.23 lines mm?1 and ±0.005 lines mm?1, respectively at groove density of ~1740 lines mm-1 of holographic laser pulse compression gratings. A simple single detector based optical set-up with fixed optical elements to avoid mechanical eccentric errors, if any, due to goniometric movement of a rotatory stage, has been proposed to estimate absolute groove density of gratings. A modified Fizeau or a modified Michelson interferometer based optical set-up has been used to estimate inter-grating groove density errors of gratings. Various gratings from different manufacturers were examined for their absolute groove densities and inter-grating groove density errors.
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