<i>In Situ</i> Electrohydrodynamic Jet Printing-Based Fabrication of Tunable Microlens Arrays
Ya Zhong, Haibo Yu, Peilin Zhou, Yangdong Wen, Wenxiu Zhao, Wuhao Zou, Hao Luo, Yuechao Wang, Lianqing Liu
Abstract
Tunable microlens arrays (MLAs) with controllable focal lengths have been extensively used in optical sensors, biochips, and electronic devices. The commonly used method is electrowetting on dielectric (EWOD) that controls the contact angle of the microlens to adjust the focal length. However, the fabrication of tunable MLAs at the microscale remains a challenge because the size of MLAs is limited by the external electrodes of EWOD. In this study, a highly integrated planar annular microelectrode array was proposed to achieve an electrowetting tunable MLA. The planar microelectrode was fabricated by electrohydrodynamic jet (E-jet) printing and the liquid microlens was then deposited in situ on the microelectrode. This method could realize 36 tunable liquid microlenses with an average diameter of 24 μm in a 320 × 320 μm2 plane. The fabricated tunable MLAs with higher integration levels and smaller sizes can be beneficial for cell imaging, optofluidic systems, and microfluidic chips.