A S JOSHI
Articles written in Sadhana
Volume 44 Issue 3 March 2019 Article ID 0059
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.