A single crystal silicon mirror technology based on BSOI (Bonded Silicon on Insulator) wafers is presented to fabricate 1D and 2D scanning mirrors. An in-plane electrode configuration is used to resonantly drive the mirror. The optical, mechanical and sensorial requirements are discussed in particular for projection applications. The Image quality of dynamically deformed mirrors is treated by the modulation transfer function. A design approach for the mirror suspension is presented to achieve a lower degree of dynamic deformation and thus to minimize image quality degradation. The fracture probability of torsional springs is treated by a Weibull statistic. A separation approach is used to compare springs of various shape and load. For amplitude and phase control a novel integrated piezoresistive transducer is presented which can be fabricated without any additional implantations. The potential of the single crystal silicon micro mirrors is demonstrated by an ultra compact VGA projector and a micro laser camera for endoscopes

In this paper we present a MOEMS based miniaturized Fourier-transform infrared (FTIR) spectrometer capable to perform time resolved measurements from NIR to MIR. The FTIR-spectrometer is based on a MOEMS translatory actuator which replaces the macroscopic mirror drive enabling a miniaturized, robust and low cost FTIR system. The MOEMS device is manufactured in a CMOS compatible process using SOI technology. Due to the electrostatic driving principle based on in-plane electrode combs, 200 µm stroke can be achieved with comparatively low voltages (<40 V) at an ambient pressure below 500 Pa. The actuator plate, acting as mirror with an area of 1.65 mm2, operates at a resonant frequency of 5 kHz. Consequently this yields a maximum spectral resolution of 25 cm-1 and an acquisition time of 200 µs per spectrum. Based on a Michelson setup the infrared optical bench of the presented FTIR system is designed to account for the mirror aperture and the desired spectral bandwidth of 2 µm to 5 µm. The integrated signal processing electronics has to cope with a bandwidth of 8 MHz as a result of the mirror motion. A digital signal processor manages system control and data processing. The high acquisition rate and integration level of the system makes it appropriate for applications like process control and surveillance of fast reactions. First results of transmission and absorbance measurements are shown. In addition we present a novel MOEMS device with increased mirror aperture and stroke which will be used for further optimization of the spectral FTIR-resolution

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We present several types of translatory MOEMS actuators developed for fast optical-path-length modulation ͓e.g., in confocal microscopes or Fourier-transform infrared ͑FTIR͒ spectrometers͔ and their application on miniaturized FTIR spectrometers capable of performing time-resolved measurements from the near infrared to the mid infrared. The MOEMS devices are manufactured in a complementary metal oxide semi conductor compatible silicon-on-insulator process. They are electrostatically resonant, driven using in-plane comb drives. A first translatory 5-kHz MOEMS device is used in a first prototype of a miniaturized MOEMS-based FTIR spectrometer where the MOEMS actuator replaces the macroscopic mirror drive, enabling a miniaturized, robust, and lowcost FTIR system. The mirror plate of 1.65 mm 2 is suspended by bending springs. Due to the resonant operation, a 200-m stroke can be achieved with low voltages ͑Ͻ40 V͒ at an ambient pressure below 500 Pa. Consequently, this yields a spectral resolution of 25 cm −1 and an acquisition time of 200 s per spectrum. In addition, we present a novel MOEMS device with an increased mirror aperture of 7.1 mm 2 and pantograph-like mirror suspension enabling up to a 500-m stroke. This device is specifically optimized for miniaturized FTIR spectrometers to enable an improved spectral resolution of 10 cm −1 and a signal-to-noise ratio of Ͼ1000: 1.

We present a Fourier-transform infrared (FTIR) spectrometer where a micro-opto-electro-mechanical system (MOEMS) replaces the macroscopic mirror drive enabling a miniaturized, robust and low cost system. The MOEMS devices are manufactured in a CMOS compatible process on a silicon on insulator (SOI) substrate. The device consists of a metallized actuator plate with an area of 1.65 mm2 acting as mirror, bearing springs and electrodes for the electrostatic drive. Due to the driving principle based on in-plane electrode combs, 200m translatory displacement can be achieved with comparatively low voltages (<40 V) at an ambient pressure below 500 Pa. The actuator operates at a resonant frequency of 5 kHz. Consequently this yields a maximum spectral resolution of 25 cm-11 and an acquisition time of 200 s per spectrum. Based on a Michelson setup the infrared optical bench of the presented FTIR system is designed to account for the mirror aperture and the desired spectral band width of 2 m to 5m. The integrated signal processing electronics has to cope with a bandwidth of 8 MHz as a result of the mirror motion. A digital signal processor manages system control and data processing. Furthermore, high-level analysis algorithms can be applied without the need of an external PC. The high acquisition rate and integration level of the system makes it appropriate for applications like process control and surveillance of fast reactions. First results of transmission and absorbance measurements are shown