Lamellar-Grating-Based MEMS Fourier Transform Spectrometer

Design, fabrication, and characterization of a high-performance micromachined lamellar-grating-interferometer-based Fourier transform spectrometer are presented. The device is designed to give high deflections with very low dynamic deformation and good mode separation. Mechanical self-stoppers are introduced to withstand accelerations larger than 500 g due to shock. The clear aperture area of the grating is about 10 mm2. The maximum deflection while electrostatically actuated at ambient conditions is ±356 μm at 71.2 V and 340 Hz, setting a record for comparable devices. At a pressure of 8.6 Pa, the same deflection is reached at 4.3 V. Six hundred eighty spectra per second can be recorded with a resolution of 14 cm-1. With a HeNe laser at 633 nm, a spectral resolution of 0.54 nm (22 cm-1) is reached using electrostatic actuation. The microelectromechanical systems device is integrated into a compact Fourier transform spectrometer setup including a blackbody source, an infrared (IR) detector, and a visible laser using the device back side for reference. Early results with IR interferograms are also reported. In addition, the devices are actuated with pressure waves in the ambient air to reach deflections up to ±700 μm. With this setup, the spectrum of a red laser is measured with a resolution of 0.3 nm (12.4 cm-1).

[1]  P. Griffiths Fourier Transform Infrared Spectrometry , 2007 .

[2]  S.K. De,et al.  Full-Lagrangian schemes for dynamic analysis of electrostatic MEMS , 2004, Journal of Microelectromechanical Systems.

[3]  W. Scherf,et al.  A compact spectrometer based on a micromachined torsional mirror device , 2004, Proceedings of IEEE Sensors, 2004..

[4]  Hakan Urey,et al.  Torsional MEMS scanner design for high-resolution display systems , 2002 .

[5]  D. Kunze,et al.  Large deflection micromechanical scanning mirrors for linear scans and pattern generation , 2000, IEEE Journal of Selected Topics in Quantum Electronics.

[6]  Caglar Ataman,et al.  A Fourier transform spectrometer using resonant vertical comb actuators , 2006 .

[7]  Andreas Kenda,et al.  Translatory MEMS actuators for optical path length modulation in miniaturized Fourier-transform infrared spectrometers , 2008 .

[8]  Caglar Ataman,et al.  Modeling and characterization of comb-actuated resonant microscanners , 2005 .

[9]  Stephan Lüttjohann,et al.  Lamellar grating optimization for miniaturized fourier transform spectrometers. , 2009, Optics express.

[10]  Wilfried Noell,et al.  Miniature lamellar grating interferometer based on silicon technology. , 2004, Optics letters.

[11]  John Strong,et al.  Lamellar Grating Far-Infrared Interferomer , 1960 .

[12]  Hakan Urey,et al.  Comb-Actuated Resonant Torsional Microscanner With Mechanical Amplification , 2010, Journal of Microelectromechanical Systems.

[13]  Andreas Kenda,et al.  Miniaturized FTIR-spectrometer based on optical MEMS translatory actuator , 2007, SPIE MOEMS-MEMS.

[14]  O Manzardo,et al.  Miniaturized time-scanning Fourier Transform Spectrometer based on silicon technology , 1999, Photonics West - Micro and Nano Fabricated Electromechanical and Optical Components.

[15]  P. Brosens Dynamic mirror distortions in optical scanning. , 1972, Applied optics.

[16]  Andreas Kenda,et al.  Improved MOEMS-based ultra-rapid Fourier transform infrared spectrometer , 2009, Defense + Commercial Sensing.

[17]  William B. Hasselbrack,et al.  A MEMS-based fourier transform spectrometer , 2003 .

[18]  N. C. MacDonald,et al.  Five parametric resonances in a microelectromechanical system , 1998, Nature.

[19]  Caglar Ataman,et al.  Compact Fourier transform spectrometers using FR4 platform , 2009 .

[20]  Caglar Ataman,et al.  Nonlinear frequency response of comb-driven microscanners , 2004, SPIE MOEMS-MEMS.

[21]  H. H. Tawfik,et al.  Nonlinear Dynamics of Spring Softening and Hardening in Folded-MEMS Comb Drive Resonators , 2011, Journal of Microelectromechanical Systems.

[22]  W. Davis,et al.  Measuring Quality Factor From a Nonlinear Frequency Response With Jump Discontinuities , 2011, Journal of Microelectromechanical Systems.