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A new generation of micromirror arrays (MMAs) with torsional actuators is being developed within the European research project MEMI in order to extend the usable spectral range of diffractive MMAs from deep ultraviolet into the visible and near infrared. The MMAs have 256 x 256 pixels reaching deflections above 350 nm at a frame rate of 1 kHz, which enables an operation in the target wavelength range between 240 nm and 800 nm. Customized driver electronics facilitates computer controlled operation and simple integration of the MMA into various optical setups. Tests in the visible wavelength range demonstrate the functionality and the high application potential of first MMA test samples

The present article discusses an optical concept for the characterization of diffractive micromirror arrays (MMAs) within an extended wavelength range from the deep ultra-violet up to near-infrared. The task derives from the development of a novel class of MMAs that will support programmable diffractive properties between 240 nm and 800 nm. The article illustrates aspects of the achromatic system design that comprises the reflective beam homogenization with divergence control and coherence management for an appropriate MMA illumination as well as the transfer of phase modulating MMA patterns into intensity profiles for contrast imaging. Contrast measurements and grey scale imaging demonstrate the operation of the characterization system and reflect the encouraging start of technology development for multispectral, diffractive MMAs

The MEMS Phase Former Kit developed by the Fraunhofer IPMS is a complete Spatial Light Modulator system based on a piston-type Micro Mirror Array (MMA) for the use in high-resolution, high-speed optical phase control. It has been designed for an easy system integration into an user-specific environment to offer a platform for first practical investigations to open up new applications in Adaptive Optics. The key component is a fine segmented 240 x 200 array of 40 µm piston-type mirror elements capable of 400 nm analog deflection for a 2pi phase modulation in the visible. Each mirror can be addressed and deflected independently by means of an integrated CMOS backplane address circuitry at an 8bit height resolution. Full user programmability and control is provided by a newly developed comfortable driver software for Windows XP based PCs supporting both a Graphical User Interface (GUI) for stand-alone operation with pre-defined data patterns as well as an open ActiveX programming interface for a closed-loop operation with real-time data from an external source. An IEEE1394a FireWire interface is used for high-speed data communication with an electronic driving board performing the actual MMA programming and control allowing for an overall frame rate of up to 500 Hz. Successful proof-of-concept demonstrations already have been given for eye aberration correction in ophthalmology, for error compensation of leightweight primary mirrors of future space telescopes and for ultra-short laser pulse shaping. Besides a presentation of the basic device concept and system architecture the paper will give an overview of the obtained results from these applications

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