Theoretical and finite element analysis of dynamic deformation in resonating micromirrors
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Dynamic deformation is one of the limiting factors in the design of high frequency resonating microscanners that are intended for high definition raster scanning display applications. Out-of-plane deformation resulting from high acceleration loads causes beam divergence, which will in turn reduce the optical resolution. This paper presents a detailed analysis on the mechanical design aspects contributing to dynamic deformation such as the micromirror layout and the micromirror-spring linkage design. The applicability of one-dimensional plate bending theory in evaluating micromirror deformation due to inertial loads is investigated using finite element analysis. Improved analytical dynamic deformation predictions, which take into consideration the two-dimensional mirror plate twist, will also be presented. A comparison among a number of layout designs was carried out with the aim of increasing micromirror bending stiffness in a direction parallel to the axis of rotation. Moreover, spring-linkage effects were also addressed and a significant improvement in dynamic deformation was achieved with the inclusion of a gimbal structure between the micromirror and the torsion springs. A parametric analysis was also carried out in order to optimise the gimbal frame design in order to comply with the Rayleigh diffraction limit criterion.
The work presented in this paper is part of the research undertaken by the authors in Lab4MEMSII, which is an ENIAC Joint Undertaking financed project.
- Freeman M, Champion M, Madhavan S (2009) Scanned laser pico-projectors: seeing the big picture (with a small device). Optics and photonics news, pp 28–34, May 2009Google Scholar
- Grahmann J, Wildenhain M, Grasshoff T, Gerwig C, Dallmann H-G, Wolter A, Schenk H (2012) Laser projector solution based on two 1D resonant scanning micro mirrors assembled in a low vertical distortion scan head. In: MOEMS and miniaturized systems XI, San Francisco, 2012Google Scholar
- Hofmann U, Oldsen M, Quenzer H-J, Janes J, Heller M, Weiss M, Fakas G, Ratzmann L, Marchetti E, D’Ascoli F, Melani M, Bacciarelli L, Volpi E, Battini F, Mostardini L, Sechi F, De Marinis M, Wagner B (2008) Wafer-level vacuum packaged resonant micro-scanning mirrors for compact laser projection displays. In: MOEMS and miniaturized systems VII, San Jose, 2008Google Scholar
- Soemers H, Krastev K, van Lierop D (2008) Design of a high frequency MEMS scanning mirror. In: American society for precision engineering 23rd annual meeting, portlandGoogle Scholar
- Timoshenko S, Woinowsky-Kreiger S (1987) Theory of plates and shells. McGraw-Hill Book Company, pp 79–82Google Scholar
- Urey H, Wine D, Osborn T (2000) Optical performance requirements for MEMS-scanner based microdisplays. In: MOEMS and miniaturized systems conference, Santa Clara, 2000Google Scholar
- Urey H, DeWitt F, Luanava S (2002) Optical scanners for high resolution RSD systems. In: Helmet- and head-mounted displays VII, Orlando, 2002Google Scholar
- Wolter A, Klose T, Hsu S-T, Schenk H, Lakner H (2006) Scanning 2D micromirror with enhanced flatness at high frequency. In: MOEMS display, imaging, and miniaturized microsystems IV, San Jose, 2006Google Scholar
- Zhang S, Ataman C, Zappe H (2016) Compact architecture for high-frequency resonant microscanners with low dynamic deformation. In: International conference on optical MEMS and nanophotonics, Singapore, 2016Google Scholar