Visualization_1.avi

Optimization visualization of a 300-unit-cell focusing metalens using the proposed two-level optimization framework. The animation depicts the iterative optimization process, showing the current optimization window (grey), far-field intensity propagated to focal plane (red), and three unwrapped phase profiles: nominal hyperbolic phase (green), phase inherited from last local generation (dashed blue), and the optimized phase (solid blue). Each frame reveals the global generation, window index, and local generation as marked in the title, illustrating the increasing fitness value (the focal spot's intensity), and the near-field phase convergence towards the target phase profile throughout the process.