Lorentz Force Actuated Tunable-Focus Liquid Lens

Abstract

Tunable-focus liquid lenses provide focal length tuning for optical systems, e.g., cameras, where physical movement of rigid lenses are not an option or not preferable. In this work we present a magnetically actuated liquid lens utilizing the Lorentz force to vary the focal length as the current through the system is varied. The resulting lens can operate as both a diverging and a converging lens depending on the direction of current applied and has a large range of focal lengths, from −305 mm to –111 mm and from 272 mm to 146 mm. We also characterized the aberrations of the lens during the actuation with a Shack–Hartmann wavefront sensor, and utilized the lens for imaging, during which we measured a resolution of 7.13 lp/mm.

Design and fabrication of compound varifocal lens driven by polydimethylsiloxane film elastic deformation

“…[23] In 2019, Van Grinsven et al presented a liquid lens actuated by the Lorentz force, whose corresponding focal length can vary with the working current. [24] In 2020, Jamali et al developed a liquid crystal lens for presbyopia correction, and its diopter successfully changes from 1.5 D to 0 D. [25] These electrically or mag-netically actuated variable focus liquid lens have advantages of no mechanical movement, simple structure, low cost, and high compatibility. [21][22][23][24][25] However, these liquid-filled lenses are prone to leakage, evaporation and fluidity, resulting in unstable lens performance.…”

“…[24] In 2020, Jamali et al developed a liquid crystal lens for presbyopia correction, and its diopter successfully changes from 1.5 D to 0 D. [25] These electrically or mag-netically actuated variable focus liquid lens have advantages of no mechanical movement, simple structure, low cost, and high compatibility. [21][22][23][24][25] However, these liquid-filled lenses are prone to leakage, evaporation and fluidity, resulting in unstable lens performance. A nonmechanical varifocal lens with better stability, fast response, high modulation accuracy is urgently desirable for high-performance optical systems.…”

An electromechanically driven dielectric elastomer based tunable reflector

“…In addition to this, there is a growing body of literature that focuses on variable curvature refractors, such as a thick liquid crystal-based system, where the focal length variability is achieved by altering the applied potential [11]. The Alvarez lens array system, which achieves variable curvature through lateral translations [12], and the use of the Lorentz force to deform soft lenses for concave and convex geometries [13], represent additional instances of these refractors. Additionally, a variable curvature lens can also be achieved by harnessing the temperature-dependent properties of soft hydrogel [14].…”