The paper presents a current development in the field of high-speed spatial light modulators. The Digital Micromirror Device (DMD) developed and produced by Texas Instruments Inc. (TI) stimulated new approaches in photonics. Recently, TI introduced the Discovery general purpose chipset to support new business areas in addition to the mainstream application of DMD technology in digital projection. ViALUX developed the ALP parallel interface controller board as a Discovery 1100 accessory for high speed micromirror operation. ALP (Accessory Light Modulator Package) has been designed for use in optical metrology but is widely open for numerous applications. It allows for rapid launch into new DMD applications and can be integrated instantly into existing systems or may initiate new developments. The paper describes both, the general hardware architecture and the software concept of the new high-speed controller solution. Binary and gray-value patterns of variable bit-depth can be pre-loaded to on-board SDRAM via USB and transferred to DMD at high speed (up to 6900 XGA frames per second). Three examples are to illustrate how the approach enables advanced applications of DMD technology in metrology, testing and beyond.

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Design, manufacturing and test of microcomponents generate new challenges for measurement techniques in general. The non-contacting operation of optical metrology makes it attractive to solve the task of measuring geometric quantities of microparts. So far, speckle interferometry (ESPI) is well established as a measuring tool for analyzing deformation, vibration and strain on a macroscopic level. This paper deals with possibilities and application limits of ESPI in the case of scaling down the object size below one millimeter. In a first part, both spatial resolution and displacement sensitivity of the technique are discussed. Theoretical considerations are shown together with experimental verification. Secondly, a micro speckle interferometer will be presented that has been built for the the use with different microscopes. Its capabilities are demonstrated by a practical application. The microcomponent under investigation is a bulk micromachined gyroscope, a demanding object with respect to its multilayer design. Developments aim at increasing the spatial resolution step by step and results obtained with different field of view will demonstrate the progress. Finally, the deformation behaviour of an X-shaped torsional spring with a width of 100 .tm could be characterized.

The paper presents an advanced solution for capturing the height of an object in addition to the 2D image as it is frequently desired in machine vision applications. Based upon the active fringe projection methodology, the system takes advantage of a series of patterns projected onto the object surface and observed by a camera to provide reliable, accurate and highly resolved 3D data from any scattering object surface. The paper shows how the recording of a projected image series can be significantly accelerated and improved in quality to overcome current limitations. The key is ALP -a metrology dedicated hardware design using the Discovery 1100 platform for the DMD micromirror device of Texas Instruments Inc. The paper describes how this DMD technology has been combined with latest LED illumination, high-performance optics, and recent digital camera solutions. The ALP based DMD projection can be exactly synchronized with one or multiple cameras so that gray value intensities generated by pulse-width modulation (PWM) are recorded with high linearity. Based upon these components, a novel 3D measuring system with outstanding properties is described. The "z-Snapper" represents a new class of 3D imaging devices, it is fast enough for time demanding in-line testing, and it can be built completely mobile: laptop based, hand-held, and battery powered. The turnkey system provides a "3D image" as simple as an usual b/w picture is grabbed. It can be instantly implemented into future machine vision applications that will benefit from the step into the third dimension.

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