Large Stroke MOEMS Actuators for Optical Path LengthModulation in miniaturized FTIR-Spectrometers

摘要

In this paper we present a novel translatory MOEMS device with extraordinary large stroke especially designed for fastoptical path modulation in an improved miniaturized Fourier-transform infrared (FTIR) spectrometer capable to performtime resolved measurements from NIR to MIR. Recently, we presented a first MOEMS based FTIR system using adifferent translatory MOEMS actuator with bending suspensions of the mirror plate and ±100μm oscillation amplituderesulting in a limited spectral resolution of 30 cm~(-1). For the novel MOEMS actuator an advanced pantograph suspension of the mirror plate was used to guarantee anextraordinary large stroke of up to 500 gm required for an improved spectral resolution. To optimize the opticalthroughput of the spectrometer the mirror aperture was increased to 7 mm~2. The MOEMS actuators are driven electrostatically resonant using out-of-plane comb drives and operate at a resonant frequency of 500 (1000) Hz, respectively.Hence, this enables to realize an improved MOEMS based FTIR-spectrometer with a spectral resolution of up to 10 cm~(-1),a SNR of > 1000:1 and an acquisition time of 1 ms per spectrum of the miniaturized FTIR-system. In this article we discuss in detail the design and the experimental characteristics of the novel large stroke translatoryMOEMS device. The application and system integration, especially the optical vacuum packaging, of this MOEMSdevice in an improved miniaturized MOEMS based FTIR spectrometer enabling ultra rapid measurements in the NIR-MIR spectral region with 12cm~(-1)spectral resolution is discussed in a separate paper submitted to this conference.