Micro-mirror Supervisor: Prof. Kämper Team member: Chun Wa George Young Issis Contreras Ramanathan Swaminathan Spandan Shroff Micromechatronics System FH AACHEN University of Applied Science

small size low cost, fast response – filter unwanted wavelengths high signal to noise ratio reduced complexity and low power consumption Advantage of MEMS Spectrometer over conventional

Key features of micromirror array a 100% fill-factor minimum surface roughness and high reflectivity (ideally 100%) in the wavelength range of interest zero insertion loss zero noise simple control identical deflection versus input energy response

A unique application of micromachined mirrors can be performance enhancement of a spectrometer by selectively focusing a particular spectral component on a detector thereby reducing the number of detectors required. improves the signal to noise ratio of the spectrometer device

IR R ANGE S PECTROMETER Sensors andActuators

D IFFRACTION GRATING Sensors andActuators

P ORTABLE U NIVERSIAL S PECTROMETER Small mirror – reducing bandpass - higher resolution But low light intensity Variable band pass filter

F ABRICATION Sensors andActuators polysilicon (poly-Si) and gold micromirror is fabricated by a surface -micromachining process Drawback: residual stress Result: curvature of the mirror surface which results in high insertion loss and crosstalk So monocrystalline silicon best results and closely resembles an ideal reflector surface.

Q UESTION Sensors andActuators The proposal is workable? Mirror size?

1 DIMENSION ARRAY MICRO MIRROR Sensors andActuators