MST Congress 2007

Dresden, /

from October 15 to October 17, 2007 in Dresden/Germany

Stand 29/39

The Fraunhofer IPMS carries out customer specific developments in fields of microelectronic and micro systems technology in Dresden, serving as a business partner that supports the transition of innovative ideas into new products. The Fraunhofer IPMS develops and fabricates modern CMOS technology products in its own clean room facilities, up to small pilot series production. With modern equipment and about 200 scientists, the range of projects and expertise covers sensor and actuator systems, microscanner, spatial light modulators, lifetronics and organic materials and systems.

At the MST Congress 2007 in Dresden the Fraunhofer IPMS presents:

1. High frequency oscillating Microscanner under stroboscopical light

The resonantly driven Micro Scanning Mirror, developed by Fraunhofer IPMS, is designed for periodical deflection of light. The actuator chip is fabricated with a CMOS compatible micromachining technology. A circular respectively elliptic silicon plate serves as mirror plate and is suspended by two torsional springs. In the case of the 2D Scanner a gimbal mounting of the mirror plate is used. The reflectivity of the mirror plate is enhanced by a thin layer of aluminium increasing the reflection coefficient to approximately 90% at 633 nm. The oscillation of the plate is excited electrostatically. The design and fabrication process of the actuator and the electrostatic driving principle enable: large optical scan range up to 80° at 20 V, oscillation frequencies ranging from 150 Hz up to 32 kHz by mirror dimensions up to 3 x 3 mm² and high mechanical stability. The mirror is used for the deflection of laser beams for one- or two-dimensional scanning e. g. of barcode, laser projection, laser marking, laser processing of materials, endoscopy and measurement solutions. The demonstrations described below base on the microscanning devices. Because of the high frequencies, it is impossible to see the mirror oscillating with the naked eye. A pulsed light source serves as stroboscopical illumination and makes the mirrors motion visible.

2. RGB laser projection module

Fraunhofer IPMS shows a full color laser projection system based on a micro scanning mirror which oscillates in 2 axis. The projection head has a size of about 2″ x 3″ x 4″ and contains the micro scanning mirror combined to 3 modulated lasers, which are controlled by a separate signal processing unit. This setup allows the projection of arbitrary images and video sequences with a geometrical resolution of 640 x 480 pixels, 256 brightness levels per pixel and elementary color at 50 frames per second. The projection module developed by Fraunhofer IPMS and Fraunhofer IOF is a milestone in developing ultra-compact displays for digital images: the very small micro scanning mirror performing beam deflection, the progress in miniaturization of lasers diodes and optical components provide opportunities of further minimizing the physical dimensions of these devices, which can display images of much larger dimensions on diffuse reflecting surfaces. For technical applications using monochrome light even much smaller projectors with dimensions comparable to a sugar cube are available today. The micro scanning mirror originated and patented by Fraunhofer IPMS is mechanically very robust, allows simple and low energy electronical control, and has good optical performance. Besides the expertise of Fraunhofer IPMS in designing and manufacturing this mirror the competence of the institute includes all necessary hardware and software development for the complete projector. This projection principle addresses markets like Infotainment in mobile devices (PDA, Laptop, …), Automotive industry (driver assistance, Head-Up Display, Infotainment), Medicine electronics (acquisition of biometrical data, positioning aid for X-Ray diagnosis and treatment), Production technology (projection of reference points for machining and tailoring workpieces and materials), and Metrology (structured lighting).

3. Customer-specific system development based on MOEMS spectrometers

Fraunhofer IPMS has developed two highly compact spectrometers for analysis of various specimen in the near infrared (NIR) and infrared range (IR). The systems make use of micro opto electro mechanical system (MOEMS) technology. One is a NIR Scanning Grating Spectrometer called SGS1900, now commercially available via the Fraunhofer IPMS spin-off HiperScan, the other is a Fourier Transform Infrared (FTIR) spectrometer currently in prototype stage. The MOEMS scanning grating resp. translational mirror are highly robust and allow for a working range from 200 nm up to 5 µm. The technology allows to fabricate the spectrometers at costs significantly below that of conventional spectrometers. At MST Congress 2007, Fraunhofer IPMS will present the spectrometer as well as demonstrate its capability to develop full featured, customer specific solutions that use the spectrometers as major component. One possible application is quality control of perishable food like fruits and vegetables as well as every kind of meat or milk product by reflectance respectively transmission spectroscopy. A demonstration system presents a recycling application.