42 mm large aperture variable-focus lens based on the liquid-membrane-liquid structure

Variable-focus lenses enable dynamic focus control and reduce the volume of the optical systems. However, few of them have been scaled up to large apertures of 10 mm , which limits their application scenarios. Here, a variable-focus lens prototype with a 42 mm large aperture based on the liquid-membrane-liquid structure was proposed and evaluated. The prototype shows a range of adjustable optical power at [−3 D , +3 D ], and demonstrates high repeatability during the operation process. The average normalized modulation transfer function value for an imaging system shows 0.7904 in 17.204 lp / mm and 0.5439 in 34.409 lp / mm . The resolution values in horizontal and vertical directions are 8 lp / mm and 8.98 lp / mm , respectively. Besides, the millisecond-level response time of the prototype is achieved with a rising edge of 5.02 ms and a falling edge of 3.66 ms . The prototype demonstrates the application scenarios of variable-focus lenses for large aperture requirements with the potential for satisfactory performance, such as in wearable devices, machine vision systems, and so on.