Staring laser situation awareness technology with wide-FOV and high-angle positioning accuracy based on two-dimensional grating and two-channels

Current and future battlefields face the emerging threat of laser weapon development. Existing laser situation awareness technology cannot provide simultaneous operation of wide field-of-view (FOV) and high angle positioning accuracy. This study introduces a system employing a two-dimensional grating and dual-channel approach that offers high precision in situation awareness about laser wavelengths and angle positioning across a wide FOV. The system consists of two main components: an approximate measurement channel and an accurate measurement channel. The former includes a wide-FOV lens and a focal plane array detector (FPA1), acquiring preliminary angle information of the laser. The latter, comprising a two-dimensional grating, a narrowFOV lens, and a FPA2, captures the incoming laser's wavelength and precise azimuth and pitch through the analysis of diffraction spot position and distance. Experimental findings confirm that the accuracies of angle and central wavelength measurements exceed 0.05 degrees and 8 nm, respectively, for a FOV of 120 degrees.