Manufactured microlenses by polimer inkjet printing

Abstract

In this work, we have studied the one single drop ejection of two photocurable inks, inkepo and inkormo, printed with nozzles of 21,5μm and 9μm of diameter. We have also established the process to manufacture the minimum microlens array that is possible to print with a cost-effective inkjet printer using two substrates of SiO2 (one bare and the other silanized). Theoretical predictions of the minimum velocity for the onset of breakup have been experimentally checked, and we have found 5m/s for an optimal waveform of 10.5μs of pulse length and a voltage range of 18-26 for both nozzles and both inks. We found that the minimum array has diameters of the drops of 15±1μm, with 31±1μm between the centres of the drops. This minimum array was manufactured on a SiO2 surface treated with a silane-based self-assembled monolayer.