Abstract
This paper presents the conception of a new micro-optical component fabricated within the wafer-level approach: a micromachined reflective objective, the so-called micro-Schwarzschild objective, characterized by superior optical performances than widespread microlenses. The system, made of two vertically integrated mirrors, works in transmission similarly as microlenses. While the specific geometric configuration of the two-mirrors allows elimination of most common optical aberrations, the reflective architecture provides inherent achromaticity. This paper presents in detail the optical design and analyzes fabrication tolerances. It also describes a fabrication flow chart based on silicon micromachining done at the wafer level that could allow production of thousands of such micro-optical devices within a single fabrication run. The realized prototype employs the two-step KOH etching process to generate the micromirror pairs followed by glass reflow for the secondary mirror generation and selective metallic deposition. Despite an insufficient mirror quality attributed to this specific silicon etching technique and highlighted by the reflective configuration, the objective fabrication in terms of alignment, bonding, and coating is shown as feasible.
© 2016 Optical Society of America
Full Article | PDF ArticleMore Like This
Maciej Baranski, Sylwester Bargiel, Nicolas Passilly, Christophe Gorecki, Chenping Jia, Jörg Frömel, and Maik Wiemer
Appl. Opt. 54(22) 6924-6934 (2015)
Jorge Albero, Lukasz Nieradko, Christophe Gorecki, Heidi Ottevaere, Virginia Gomez, Hugo Thienpont, Juha Pietarinen, Birgit Päivänranta, and Nicolas Passilly
Opt. Express 17(8) 6283-6292 (2009)
D.W. de Lima Monteiro, O. Akhzar-Mehr, P.M. Sarro, and G. Vdovin
Opt. Express 11(18) 2244-2252 (2003)