Discussion on the Phase-Correction Mirror in the Quasi-Optical Mode Converter

This work report investigations on the phase-correction mirror design for the Quasi-Optical mode converter. Specifically, the last mirror in a three-mirror converter system is generated by phase-correction, and its performance of pure Gaussian beam shaping is analyzed via different incident beam conditions. Based on numerical analysis, it can be concluded, the key for a good Gaussian conversion is that the magnitude pattern of the incident beam should be close to round Gaussian before the phase correction. That can be considered as the principle of beam shaping in the Quasi-Optical mode converters.