Continuous phase plate design based on magnetorheological finishing (MRF) technology

The design and manufacture of Continuous Phase Plates (CPPs) with a large aperture is very significant and useful for kilojoule and megajoule-class laser systems, such as the Inertial Confinement Fusion(ICF) due to it has the advantages of precise control of beam-shape and high energy availability ratio. In order to improve the quality of the focused beam in the Inertial Confinement Fusion (ICF) system and reduce the processing difficulty of components, a theoretical design model of the continuous phase plate based on the Magnetorheological Finishing (MRF) technology was established, and improved the traditional Gerchberg-Saxton (GS) algorithm from the aspects of initial phase selection, phase unwrapping, filtering, and speckle spectrum control. The results show that: Compared with the conventionally designed continuous phase plate (CPP), the improved GS algorithm can control the size of the CPP processing unit, meet the requirements of magnetorheological processing technology, better control the focal spot profile, and reduce the modulation of specific frequency bands.