Designing X-Band Lenses With the Adjoint Method and 3-D Printing Techniques

In this study, we employ the adjoint method to design a Gradient Index (GRIN) lens at 10 GHz, optimizing the dielectric constant at each point to meet specific goal functions. Our optimization framework incorporates a 2D FFT-integral equation solver, delivering solutions within seconds. The entire optimization process is completed in just minutes, presenting a highly efficient approach to lens design. The optimized lens is fabricated using advanced 3D printing techniques, ensuring high precision and costeffective manufacturing. The resulting design features a unique ring-shaped lens with a central piece of lower contrast, weighing a total of 207 grams and achieving an aperture efficiency of 55.9 experimentally measured, confirming the effectiveness of the proposed method. The 3D printing process facilitates the rapid prototyping of such GRIN lenses, demonstrating its potential for applications requiring lightweight and compact designs. This approach opens avenues for further optimization and practical applications in communication systems and beyond.