Electrostatic–pneumatic activation
Electrostatic–pneumatic activation is an actuation method for shaping thin membranes for microelectromechanical and microoptoelectromechanical systems.[1][2] This method benefits from operation at high speed and low power consumption.[3] It can also cause large deflection on thin membranes. Electrostatic-pneumatic MEMS devices usually consist of two membranes with a sealed cavity in between. One membrane calling actuator deflects into cavity by electrostatic pressure to compress air and increase air pressure. Elevated pressure pushes the other membrane and cause dome shape. With direct electrostatic actuation on membrane, a concave shape is achieved.
This method is used in MEMS deformable mirrors[4][5] [6][7][8] to create convex and concave mirrors.[9] Electrostatic-pneumatic actuation can double maximum displacement of a thin membrane compared to only electrostatic actuated membrane.[10]
Moreover, mechanical advantage[11] is possible by use of electrostatic-pneumatic actuation. Since the cavity is filled with air, mechanical amplification is lower than hydraulic machinery with a non-compressible fluid.
References
- K. J. Gabriel, O. Tabata, K. Shimaoka, S. Sugiyama, H. Fujita "Surface normal electrostatic/pneumatic actuator" Micro Electro Mechanical Systems 92 Travemunde (Germany), Feb. 1992
- Cleopatra Cabuz, Thomas R. Ohnstein, Michael R. Elgersma (2000), "Electrostatic/pneumatic actuator for active surfaces" US Patent No. 09/573,460
- Moghimi, M. J. Chattergoon, K. N. Dickensheets, D. L. “High speed focus control capability of electrostatic–pneumatic MEMS deformable mirrors” in Proc. SPIE 8977, MOEMS and Miniaturized Systems XIII, San Francisco, CA, Mar. 2014, pp. 897709, 897709-9
- Bifano, Thomas (2011). "Adaptive imaging: MEMS deformable mirrors". Nature Photonics. 5: 21–23. doi:10.1038/nphoton.2010.297.
- Moghimi, Mohammad J.; Chattergoon, Krishna N.; Wilson, Chris R.; Dickensheets, David L. (Aug 2013). "High Speed Focus Control MEMS Mirror With Controlled Air Damping for Vital Microscopy". Journal of Microelectromechanical Systems. 22 (4): 938–948. doi:10.1109/JMEMS.2013.2251320.
- Moghimi, Mohammad J (1 April 2011). "MOEMS deformable mirrors for focus control in vital microscopy". Micro Nanolithography MEMS MOEMS. 10 (2): 023005. doi:10.1117/1.3574129. Retrieved 1 April 2011.
- "mirao™ 52-e Deformable Mirror".
- "MFC Series MEMS Adjustable Focus Mirrors".
- Moghimi, M. J. Wilson, C. Dickensheets, D. L. “Electrostatic-pneumatic membrane mirror with positive or negative variable optical power” in Proc. SPIE 8617, MEMS Adaptive Optics VII, San Francisco, CA, Mar. 2013, pp. 861707-1, 861707-9
- Moghimi, M. J. Wilson, C. R. Dickensheets, D. L., “Electrostatic-pneumatic MEMS deformable mirror for focus control” 2012 International Conference on Optical MEMS and Nanophotonics (OMN), Banff, Canada, August 2012, pp. 132-133.
- Bansal, R. K. (1 Jan 2004). A TextBook of Theory of Machines. Firewall Media. ISBN 9788170084181.