Fabrication of low-cost polymer microlens array

Abstract

The fabrication technology of refractive microlens array (MLA) with self-assembly of drops of various thermoplastic optical polymer solutions is reported. In order to develop a conventional drop-on-demand type ink-jet printing method for fabricating high quality microlens array, Firstly, we tried to prepare a series of optical polymer inks. These inks compose of high quality optical polymers, polymethylmethacrylate (PMMA), dopant, and functional organic molecules such as laser dye, nonlinear organic dye, and rare earth ion chelates with a suitable organic solvent. Effects of surface tension on the polymer solution drops induced the self-formation of microlenses. This process exhibited a completely self-assembly characteristic without any chemical and photochemical post-treatment. The resulting microlens array displayed diameters varying from 1mm to 5mm and focal lengths from less than one millimeter to a few millimeters. Observation with an atomic force microscope reveals that the surface roughness of the lens is 0.9 nm. The transmittance spectrum of the lens is also measured.

Oberflächenfunktionalisierung 3D‐gedruckter transparenter Optiken

“…Bisher konnten gute Ergebnisse für sehr kleine Optiken mittels Direct Laser Writing und Inkjet-Drucken erzielt werden. Die Größenordnungen der mikrooptischen Komponenten, wie Linsenarrays, Endoskope oder Prismen, liegen im Bereich von einigen 10 nm bis zu einigen 100 µm und zeigen eine hohe Formgenauigkeit und Oberflächenqualität mit einer Rauheit zwischen 1 und 15 nm rms [3,4]. Bei den verwendeten Materialien handelt es sich um UV-aushärtende Fotopolymere und Hybridmaterialien, welche bei einer bestimmten Wellenlänge polymerisieren.…”

Development of collagen scaffold with internal channels via indirect rapid prototyping

“…It is a technology that has found its way in various industries outside the graphic art-printing field. Examples of applications include: biomedical and chemical sample handling [147][148][149], fuel mixing control [150,151], direct writing and packaging [152][153][154], optical component fabrication [155,156], micro fabrication [157,158], rapid prototyping [159][160][161] and manufacturing processes [162][163][164][165].…”