On-line beam diagnostic method for high energy laser with large beam profile.

A novel on-line beam diagnostic method for continuous-wave high energy laser (HEL) is presented. The system based on this method is mainly consisted of a scanning circular reflector and a photodetector array disposed spatially. Laser beam passes through the system except a little part of whole beam is sampled and reflected into the detector array by the circular reflector. Through the arithmetic of spatial mapping and image restoration with the output signal of detector array, the spatial-temporal distribution parameters of the laser beam are obtained. The HEL beam of several hundred millimeters in diameter can be on-line measured with spatial resolution of 2 mm and temporal resolution of 30~50ms.