Seidel-compatible initial-structure calculation method for hybrid refractive-metalens zoom systems

Hybrid refractive-metalens zoom systems offer a promising route to overcome the size, mass, power consumption, cost, and response-time limitations of conventional mechanically compensated refractive zoom systems by exploiting the high degrees of freedom in wavefront manipulation provided by tunable metalenses. A Seidel-compatible initial-structure calculation method is presented for axially fixed hybrid zoom optical systems. The method applies to architectures containing two tunable metalens groups and fixed refractive elements arranged arbitrarily. By treating the Seidel aberrations of the tunable metalens groups as known quantities in an extended Mikš third-order aberration matrix, we reformulate the inverse determination of the fixed refractive-element parameters as a linear least-squares problem. This approach yields physically interpretable and aberration-compatible initial structures, which can be directly imported into optical design software such as Zemax. Case studies on two classical configurations-Alvarez and Moiré-demonstrate that the method enables starting configuration calculation for hybrid refractive-metalens zoom optical systems, transforming the configuration search from empirical trial-and-error into a physics-driven parameter-determination problem and thereby providing a physically interpretable starting point for subsequent image quality optimization.