Van Grinsven Kari L, Ousati Ashtiani Alireza, Jiang Hongrui
Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA.
Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA.
Micromachines (Basel). 2019 Jul 11;10(7):464. doi: 10.3390/mi10070464.
We have fabricated a fully-flexible, focus-tunable microlens array on a sheet and demonstrated its imaging capabilities. Each liquid lens of the array is individually tunable via electrowetting on dielectric (EWOD) actuation and is situated on a polydimethylsiloxane (PDMS) substrate, which allows the lens array to operate as a reconfigurable optical system. In particular, we observed a significant increase in the field of view (FOV) of the system to 40.4° by wrapping it on a cylindrical surface as compared to the FOV of 21.5° obtained by the array on a planer surface. We also characterized the liquid lenses of the system, observing a range of focus length from 20.2 mm to 9.2 mm as increased voltage was applied to each EWOD lens. A Shack-Hartmann wavefront sensor (SHWS) was used to measure the wavefront of the lens as it was actuated, and the aberrations of the lens were assessed by reporting the Zernike coefficients of the wavefronts.
我们在一片材料上制作了一个全柔性、焦点可调的微透镜阵列，并展示了其成像能力。该阵列的每个液体透镜可通过介电层上电润湿（EWOD）驱动单独调焦，且位于聚二甲基硅氧烷（PDMS）衬底上，这使得透镜阵列能够作为一个可重构光学系统运行。特别是，我们观察到，与该阵列在平面表面上获得的21.5°视场相比，将其包裹在圆柱表面时，系统的视场显著增加到40.4°。我们还对系统的液体透镜进行了表征，观察到随着向每个EWOD透镜施加的电压增加，焦距范围从20.2毫米到9.2毫米。在驱动透镜时，使用夏克-哈特曼波前传感器（SHWS）测量其波前，并通过报告波前的泽尼克系数来评估透镜的像差。
