Variable-focus liquid lens by changing aperture

TLDR

The key part is the annular sealing ring, which functions like an iris diaphragm. The study proposes an adaptive liquid‑filled lens comprising an elastic membrane, a solid plate, and an annular sealing ring with a fixed‑volume liquid. The lens operates by varying the radius of an iris‑diaphragm‑like annular sealing ring, which, sealed to an elastic membrane, redistributes the liquid and alters the membrane curvature to focus light. The prototype demonstrated positive variable focus and offers a simple, compact, low‑cost, and easy‑to‑operate design.

Abstract

We propose an adaptive liquid-filled lens, which consists of an elastic membrane, a solid plate, and an annular sealing ring; a liquid with a fixed volume stored in lens chamber. The key part is the annular sealing ring which looks like an iris diaphragm. The surfaces of annular sealing ring are sealed with an elastic membrane. The radius of the annular sealing ring is changeable. By tuning the radius of the annular sealing ring, the stored liquid in the lens will be redistributed, thus changing the curvature of the elastic membrane. Therefore, the lens cell causes light to converge or diverge. A liquid lens with a positive variable focus was demonstrated, this kind of lens has the advantages of simple fabrication process, compact structure, easy operation, and low cost.