Novel microactuators based on a photo-thermo-mechanical actuation strategy

In this work an innovative actuation strategy based on a photo-thermo-mechanical energy conversion is presented. The actuation energy is typically higher than those required by the control and/or signal processing electronics, therefore this means a significant stress for the power supply. This challenge is particularly important if autonomous systems are taken into account. Small batteries don't ensure sufficient autonomy, therefore external energy source should be considered. The basic idea is to provide the actuation energy to system through a light source, by directly exploiting the heat generation capability of the light. The truly innovative idea in this work is the use of micro-lenses coupled with thermal actuators to gain efficiency. The device presented here is a bimorph cantilever-beam that can be realized in any standard Si-technology. Few additional steps are required for the fabrication of the micro-lenses, commonly used for micro-optics and opto-electronics. In contrast to other off-chip power supply approaches, the one presented here does not require any structured environment or exotic materials.