Effects of laser facula detector array parameters on measurement accuracy of far-field beam quality

The detector array parameters will greatly affect the measurement accuracy of beam quality at target. In this study, the relations of the parameters with encircled power ratio and the beam radius at target were further analyzed. Since the beam at target is a Gauss-like beam, the effects of detector array's spatial resolution, effective testing area, systematic dynamic range, and surface response homogeneity on measurement accuracy of beam quality were analyzed quantitatively with numerical simulation. The results show that among all influence factors, the measurement accuracy of beam radius was greatly affected by the detector's normalized size and dynamic range, but slightly by normalized resolution and surface response homogeneity. These results were successfully applied in design of detector array and achieved good effect. The experimental data and theory are well consistent.