from January 22 to January 24, 2008 in San José/USA

South hall Stand 6239

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 240 scientists, the range of projects and expertise covers sensor and actuator systems, microscanner, spatial light modulators, lifetronics and organic materials and systems.

At the Photonics West 2008 show the Fraunhofer IPMS presents:

1. Customer-specific system development based on MOEMS spectrometers

Fraunhofer IPMS develops special Micro-Opto-Electro-Mechanical devices and complete systems for spectroscopy. One prominent example is a Czerny-Turner spectrometer called SGS1900, now commercially available via the Fraunhofer IPMS spin-off HiperScan. It uses the micro scanning mirror developed at Fraunhofer IPMS, where a blaze grating has been added to the mirror surface. Hence, the incoming light is split into its spectral components and at the same time, because of the moving of the mirror, moved across a punctiform photo detector. This principle results in a small and robust system at costs significantly below the price of conventional spectrometers. At Photonics West 2008, Fraunhofer IPMS will present its capability to develop full featured, customer specific solutions that use spectrometers as major component. A demonstrator sorting different kinds of plastics by spectroscopic measurement will be shown. Another possible application is quality control of perishable food, which can be fruits and vegetables as well as every kind of meat or milk product by reflectance or fluorescence spectroscopy.

Dr. Michael Scholles will present the system at the exhibitor forum at Tuesday, January 22, 2008, in South Hall, at 1:30 PM.

2. Laser projection systems in measurement and industrial applications

Ultra compact laser projection systems based lasers as light source and micro scanning mirrors for light deflection are considered as future products with enormous market potential for the infotainment sector, because it will be possible to integrate them into mobile devices rather soon. Image generation is achieved via the Flying Spot principle: the laser beam reflected by the two-dimensional micro scanning mirror describes a dense Lissajous pattern on the projection screen that hits every virtual pixel at least once during the time available for one image frame. By modulation of the intensity of the laser beam and the driving of the scanning mirror in a strictly synchronous manner, projection of arbitrary images can be achieved. However, also measurement and industrial applications may profit from the advantages of such systems. This is proven by the demonstrator of Fraunhofer IPMS shown at Photonics West 2008. The system detects the continuously changing distance to one object and projects the measured value on the surface of the object. Because of the quasi unlimited depth of field, the projected image is always in focus. Concrete applications include support of maintenance and assembly tasks, Augmented Reality and all other industrial systems, where the job will become easier for the worker if additional information is displayed.

3. MEMS Adaptive Optic Demonstrator for optical wavefront control and imaging enhancement

Adaptive Optics (AO) is mainly used for the compensation of spatially and timely varying wavefront disturbances within an optical system for an enhancement in optical imaging through inhomogeneous or turbulent media. Originally evolved from astronomy to compensate for atmospheric turbulences, AO techniques also can be used for aberration correction of the human eye in ophthalmology, for imaging through biological tissue in optical microscopy or for any kind of object recognition in machine vision. Furthermore, there are applications in laser beam shaping as well as in ultra-fast laser pulse modulation. The key component is formed by the actual wavefront controlling device. For that purpose MEMS (Micro-Electro-Mechanical-System) micro mirror arrays possess several attractive features. Due to their integrated fabrication capability they can support large pixel numbers providing an exceptional high spatial resolution for an improved reproduction especially of higher order phase aberrations. They also benefit from a step function display capability, fast mechanical response times, low power consumption, broad spectral bandwidth from IR down to DUV and polarization insensitivity. Compared to previous macroscale systems micro mirrors also offer the potential of a substantial cost decrease as well as a significant device miniaturization just facilitating completely new opportunities for a broader commercial exploitation. The Fraunhofer IPMS therefore has developed a complete MEMS Phase Former Kit. The key component is a high-resolution MEMS micro mirror array of 240 x 200 piston-type mirror elements with 40 µm pixel size providing 400 nm stroke at 8 bit resolution suitable for a 2π phase modulation in the visible. Full user programmability and control is established by a comfortable driver software for Windows XP^® PCs supporting both a Graphical User Interface as well as an open ActiveX^® programming interface for open-loop and closed-loop operation. High-speed data communication is accomplished by an IEEE1394a FireWire interface together with an electronic driving board allowing for maximum frame rates of up to 500 Hz. In order to visualize the potential for optical imaging enhancement a complete AO demonstrator system has been implemented. It basically comprises a projection system, where objects of different complexity are imaged through adaptive optics onto a CCD camera. Phase errors of different severness are introduced by rotating phase plates. Using a Shack-Hartmann sensor and the Fraunhofer IPMS MEMS micro mirror for wavefront sensing and correction respectively, the obtainable imaging improvement can be assessed by means of the recorded CCD picture, which is also projected onto a large screen. For a more quantitative anlaysis also some wavefront data without and with correction are made available.

Addressed business fields are optical system developer and manufacturer in the following areas:

• Machine Vision (in-situ process control through turbulent media)
• Optical Microscopy
• Ophthalmology
• Astronomy
• Laser Pulse Shaping
• Laser Beam Shaping
• Diffractive Optics (especially optical tweezers)