Implementation of aberration-corrected optical supercritical lenses via topology optimization

We explore the evolving landscape of planar optics, driven by a growing demand for lenses with reduced thickness and enhanced super-resolution capabilities. Traditional methods face limitations in forward design, stemming from low discrete levels, periodic arrangements, and electromagnetic coupling between structures. To address these challenges, we present a lens design employing gradient topology optimization within the inverse design paradigm. Utilizing randomly arranged topology optimization under various critical conditions, our innovative approach yields supercritical lenses surpassing the highest Fourier frequencies. The objective is to attain subwavelength planar lenses with a 100 nm structural thickness. Considering practical manufacturing constraints, convolution is introduced during optimization, limiting the structure's minimum width and simulating real-world imperfections. Expanding functionality, we optimize a complex lens design for multi-band operation through a unified structure and correct chromatic aberrations using advanced methods. Furthermore, our analysis extends to spherical and off-axis aberrations, offering valuable insights into intricate lens design.