XY-stage for alignment of optical elements in MOEMS

The alignment of optical elements in a Micro-Opto-Electro- Mechanical System, is of prime importance in order to realize a reliable and low loss system. Fabrication errors or temperature changes deteriorate the alignment accuracy. These errors can be compensated with the aid of an active alignment system. The aim of the paper is to investigate an active system in order to align microlenses and fibers. A high lateral precision is required for single mode fiber injection, typically better than 1 micrometers . The alignment along the optical axis is less critical. Our system consists of a microlens placed between one input fiber and one output fiber. The fibers are held in V-grooves and the microlens is mounted on an XY-stage. The lens is fabricated by melting resist technology and subsequent etching in quartz. The mechanical parts are realized by wire electro-discharge machining (wire-EDM). Two piezo-electrical actuators move the flexible bearings of the stage in the X and Y direction. We will present the results obtained with this system and we will discuss its potential.