Micro opto-electro-mechanical systems (MOEMS)

Micro-opto-electromechanical systems (MOEMS), or optical MEMS as they are also called, are systems involving micromachining of structures in the micro- to millimeter range whose purposes are to manipulate light. Today’s MOEMS devices include waveguides, moving mirrors and diffractive gratings, and are typically made using standard lithography methods giving the advantages of a compact design and fabrication at a low cost.

Applications of MOEMS designs developed at SINTEF MiNaLab are mainly found in sensor systems. Our most unique design today is a configurable diffractive optical element (CDOE), which is a development of a passive multi-focal diffractive optical element (DOE). The multi-focal DOE redirects chosen wavelengths of incoming light to a set of predefined positions. By tilting the element back and forth, the focal spots containing different wavelengths pass one after another across a single detector. It is today used in commercial spectrometers for identification of materials and gasses. A CDOE can have much of the same functions as the DOE, but whereas the DOE must be mechanically tilted, the CDOE does this micromechanically. This makes the CDOE a micro mechanical system that has the function of a number of beam splitters, multiple band pass filters and lenses, all in one compact design.

Other in-house MOEMS designs include a bistable Fabry Perot resonator for high accuracy measurement of gas concentration and a micro-optical microphone that can be used to measure air pressure.

Work on MOEMS at SINTEF Microsystems and nanotechnology is done in close collaboration with SINTEF Optical measurement systems and data analysis. To learn more about SINTEF’s MOEMS activity, please visit their website about micro optics.

Contact person: Ib-Rune Johansen

The illustration shows how a Micro-optic system becomes Micro-opto-electromechanical. The DOE has to be tilted by an external device, while the CDOE is designed to change its surface when a voltage is applied. The change in shape alters which frequency hits the detector.