Fast measurement technique for obtaining the diffraction efficiency and its uniformity of a large-aperture pulse compression grating

Diffraction efficiency and its uniformity are both the important performance indicators of a large-aperture pulse compression grating (PCG), and their accurate measurement is of great importance for evaluating the performance of a PCG and improving the manufacturing technique of a PCG. In this paper, based on the traditional double beam photometric measuring framework, and in combination with synchronously scanning in two-dimension the optical fiber and the detector (small size, light weight), fast measurement for the diffraction efficiency and its uniformity of a largeaperture PCG was realized. Experimental result shows that for a PCG in the size of 1400×430 mm, when the sampling intervals in both the horizontal and the vertical directions are 10 mm, the whole measurement takes about 3 hours, and a repeatability error of about 0.1% is obtained with the corresponding experiment. Compared with the currently popular measuring strategy by scanning the large-aperture PCG (large size, heavy weight), our proposed measurement system has the advantages of significantly increasing the data acquisition speed, and reducing the cost of system construction, meanwhile the safety loophole is greatly eliminated.