MEMS offers precision in optical scanner systems
silicon-based resonant and quasi-static MEMS
Fraunhofer IPMS's customised silicon-based resonant and quasi-static micro-electro-mechanical systems (MEMS) are claimed to offer highvelocity with precision in the deflection and modulation of light.
Laser sources are used in the industry for labelling and material-machining applications.
To meet demands concerning precision and processing speed, optical scanner systems are used for the modulation or deflection of light.
Compared to mechanical translation stages, Fraunhofer claims that optical scanner systems provide clear benefits regarding positioning accuracy and repeatability, as well as high dynamics.
Conventional galvanometer-based optical scanners typically feature large optical apertures.
However, the macroscopic design limits the precision of motion, particularly at high velocity.
Requirements for the bearings of moving parts are exceptionally high.
A characteristic measure for the quality of motion is the dynamic mirror tilt perpendicular to the axis of rotation.
Mirror tilt leads to a tumbling motion and a deformation of the projected figure, which is often referred to as cross-axes wobble.
Cross-axes wobble of conventional resonant galvanometer scanners is typically in the order of 200urad.
Scientists have demonstrated that typical resonant designs provide a cross-axes wobble of less than 35urad.
For this reason, Fraunhofer's device oscillates at 23kHz, with a mechanical amplitude of +/-9deg.
According to the company, the optical MEMS structures of the Fraunhofer IPMS are suitable for use in challenging applications with high demands on velocity and precision of motion at the same time.