Aberration principles behind an AI-based design method of zoom lens groups (Invited Paper)

The lens groups of a zoom system can be designed independently using a variety of techniques, including artificial intelligence (AI). While re-optimization is still required after the lens groups are combined to form the complete zoom lens in traditional optical design software, designing the lens groups individually can speed up the design process and reveal underlying principles of zoom lens design. The optimal aberration contributions of each lens group are dictated by the paraxial layout of the zoom lens. The groups can be designed individually to have these optimal aberration contributions, as well as other favorable properties like small ray angles and short length. The lens group design problem is first explored with aberration theory, revealing limitations in the aberration contributions of lens groups with arbitrary numbers of elements. Then, lens groups from the patent literature are analyzed using the principles developed with the aberration theory, which enables a more informed approach to lens group design. Tools and methods for designing lens groups, including conventional optimization, Monte-Carlo searches, and new AI-based method, are developed and analyzed. These principles aid the designer’s understanding of the source of aberrations in zoom lenses, as well as provide theoretical justification for the prevalence of certain zoom lens design forms. Furthermore, we highlight the necessity of a strong understanding of aberration theory to successfully implement an AI based lens design program, despite the ever-increasing power of AI.