title: Two step process for the fabrication of diffraction limited concave microlens arrays.
abstract: A two step process has been developed for the fabrication of diffraction limited concave microlens arrays. The process is based on the photoresist filling of melted holes obtained by a preliminary photolithography step. The quality of these microlenses has been tested in a Mach-Zehnder interferometer. The method allows the fabrication of concave microlens arrays with diffraction limited optical performance. Concave microlenses with diameters ranging between 30 microm to 230 microm and numerical apertures up to 0.25 have been demonstrated. As an example, we present the realization of diffusers obtained with random sizes and locations of concave shapes.
authors.affiliation: Institute of Microtechnology, University of Neuchâtel, Rue Breguet 2, CH-2000 Neuchâtel, Switzerland. Patrick.Ruffieux@unine.ch
authors.forename: Patrick
authors.initials: P
authors.lastname: Ruffieux
authors.forename: Toralf
authors.initials: T
authors.lastname: Scharf
authors.forename: Irène
authors.initials: I
authors.lastname: Philipoussis
authors.forename: Hans Peter
authors.initials: HP
authors.lastname: Herzig
authors.forename: Reinhard
authors.initials: R
authors.lastname: Voelkel
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Weible