2D Quasi-Static MEMS Micro-Mirrors

Research & Development

© Fraunhofer ISIT / photocompany itzehoe
Out piezoelectric MEMS micro mirrors (left) and our module for a 3D-camera (right).

Besides our long term proven resonant mirror technology our new piezo actuator design and technology extends the application space substantially.

Fraunhofer ISIT's new generation of piezoelectric-driven MEMS scanners can achieve extreme optical scan angles close to 180° due to the high torque provided by the piezoelectric material. The achievable scanning speed and the ability to integrate two scanning axes in a very compact device are fundamental advantages of MEMS scanning mirrors over conventional galvanometric scanners.

© Fraunhofer ISIT
Design of our new quasistatic mirror generation. Left: Rosebud shaped 4 electrode / actuator structures. Right: Au coated 5 mm mirror. The mirror plate will be bonded on the small pin between the electrodes (see left picture center).

Quasistatic mirrors with angular and translational actuation


  • Rosebud shaped 4-electrode actuator design
  • Mirrors plates with diameters of 0,2 mm – 20 mm (core design 1 mm – 5 mm)
  • Metallic coatings like Au, Al, etc.
  • Optical path of z-motion of non-optimized design up to 400 µm (twice the physical motion)


© Fraunhofer ISIT
Fig. 2: Linear translation characteristics of a circular 2 mm quasistatic micro mirror. Mirrors can be coated with metals like Au and Al.

The following table shows the main parameter space where however due to physical restrictions these parameters cannot be combined arbitrarily.




Frequency / Hz

100 / quasistatic


Optical scan angle (FOV) / °



Aperture / mm



Tab. 1: Main parameters for quasistatic mirrors

Besides tilting motions with this four electrode/actuator architecture also translational or mixed mirror motions can be performed, all precisely defined in a closed-loop scheme through very accurate optical or piezoelectric position sensing. Simulations have shown that already with this first, non-optimized design large hubs up to 200 µm can be reached (fig. 2).

USPs & Benefits

  • Proven resonant mirror technology
  • New piezo actuator design for quasistatic 1D/2D motions
  • Four electrode/actuator architecture allows precise tilting, translational or mixed mirror motions.
  • Large hubs of 200 µm or beyond (depending on design)


  • [1] V. Stenchly et al., Modular packaging concept for MEMS and MOEMS. DOI.
  • [2] W. Reinert, A miniaturized RGB-laser light engine. DOI.
  • [3] S. Gu-Stoppel et al.: A triple-wafer-bonded AlScN driven quasi-static MEMS mirror with high linearity and large tilt angles. DOI.
  • [4] S. Gu-Stoppel et al.: A designing and manufacturing platform for AlScN based highly linear quasi-static MEMS mirrors with large optical apertures. DOI.