High fill factor confocal compound eyes fabricated by direct laser writing for better imaging quality

TL;DR

This paper presents the fabrication and comparison of two types of 100% fill factor compound eyes, demonstrating that confocal designs improve focusing efficiency, imaging area, and edge image quality.

Contribution

The study introduces confocal compound eye structures fabricated by direct laser writing, showing enhanced optical performance over conventional designs.

Findings

CFCEs improve focusing efficiency by ~7%

CFCEs enlarge imaging area by ~25%

CFCEs provide better edge imaging quality

Abstract

We fabricate two kinds of 100% fill factor compound eye structures using direct laser writing, including conventional compound eyes (CVCEs) with the same focal length of each microlens unit, and specially designed confocal compound eyes (CFCEs). For CFCEs, the focal length of each microlens unit is determined by its position and is equal to the distance between the microlens unit and the image sensor. In this letter, the optical properties of CVCEs and CFCEs are tested and compared. It is found that compared with CVCEs, CFCEs can improve the focusing efficiency by about 7%, enlarge the imaging area by about 25%, and have better imaging quality at the edge of the field of view.