Superposition Model for Achromatic Surface Lenses (Preprint)
Abstract
I present a model for an achromatic surface lens based on the superposition of lenses that focus discrete wavelengths independent of one another. The model potentially provides insight into the physical behavior of experimentally demonstrated lenses. It also suggests a simple design algorithm. Structured surface elements offer the potential for optical functionality in a small volume but their dispersion is a severe drawback for broadband imaging. To overcome this problem, surface lenses with heights greater than a wavelength have been used to generate coincident foci for wavelengths related harmonically. Recently, surface elements have been demonstrated that provide achromatic focusing over a band of wavelengths that are not harmonically related. Although the experimental results are indisputable, a physical explanation for their behavior is lacking. Without question, the physical mechanism differs from the one that enables dispersion control by shaping subwavelength features. I propose a model for the demonstrated behavior based on lens superposition. This model potentially provides insight into the elements physical behavior and suggests a simpler design algorithm than that used in Ref.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2021
- Accession Number
- AD1156927
Entities
People
- Joseph N. Mait
Organizations
- MITRE Corporation