Abstract
Dynamic performance is one of the most important characteristics of a variable focus lens. However, there are few studies investigating the dynamic response of a membrane-based variable focus lens. In this paper, we present a mathematical model to describe spring-damping phenomena in theory. The first order natural frequencies with different scales were confirmed via finite element analysis. We also built a dynamic response experiment platform with changeable optical apertures, which was driven by a high-speed piezo stack actuator. A photodiode module was placed behind the lens to measure the variation of light luminance as the lens changed, and a laser displacement sensor was used to measure the deformation of the membrane. A series of data was collected with different optical apertures (20 mm, 30 mm, 50 mm) and different pre-stretching ratios (200%, 300%) under different driving frequencies (from 5 Hz to 25 Hz in every 5 Hz step). The experimental results were consistent with the mathematical model, which showed that the first order natural frequency increased as the aperture decreased or the membrane stiffness increased. This frequency-dependent characteristic of the variable focus lens provides a basis for further research on its dynamic performance.
© 2023 Optica Publishing Group
Full Article | PDF ArticleMore Like This
Lihui Wang, Hiromasa Oku, and Masatoshi Ishikawa
Opt. Express 22(16) 19448-19456 (2014)
Yang Cheng, Zhikuo Li, Chuanxun Chen, Jie Cao, Chun Bao, Yan Ning, and Qun Hao
Appl. Opt. 61(15) 4633-4637 (2022)
Seung Tae Choi, Byeong Soo Son, Gye Won Seo, Si-Young Park, and Kyung-Sick Lee
Opt. Express 22(5) 6133-6146 (2014)