Laser printing of mircolenses

Abstract

Laser-Induced Forward Transfer (LIFT) is a printing method that uses a pulsed laser beam as the driving mechanism to transfer material deposited on a donor film onto a substrate. It offers the possibility to print with a high spatial resolution. In this study, we examine how the energy of the laser pulse affects the geometrical properties of the printed droplets of an optical glue that can be used as microlenses. By varying the laser pulse energy, we identify a threshold at which the droplets undergo a sudden increase in diameter while the contact angle between the material and the substrate decreases. Despite this abrupt change in diameter, a linear increase in the deposited volume is observed. Also a study of the microlenses focusing capacity has been carried out, where it is observed that with the use of a microlense we can increase the light recollection by a almost a 178%