From microchips to holograms – the perfect light modulation

These so-called spatial light modulators (SLM) are micromirror arrays with up to several million mirrors on a semiconductor chip. They have applications in semiconductor manufacturing, microscopy, and holography, and have brought the Institute to the forefront of international research in this field.

In its own laboratories and the 150 m² clean room, Fraunhofer Institute for Photonic Microsystems IPMS develops a wide variety of application-specific spatial light modulators based on 200mm wafer technology. To enable individual deflection of each micromirror, a highly integrated electronic circuit (ASIC) is used as the basis for the component architecture. In combination with monolithically integrated MEMS (Micro Electro Mechanical Systems) technology, unique micromirror arrays are created. In addition, Fraunhofer IPMS develops the electronics and software to drive the devices. To facilitate the technology transfer into application, the institute offers evaluation kits to its customers. The ready-for-trial setup includes not only the micro mirror chip itself but also the complete control electronics including software.

Fraunhofer IPMS spatial light modulators are used in deep ultraviolet microlithography, printed circuit board (PCB) manufacturing, semiconductor inspection and metrology, adaptive optics, astronomy, holography, and microscopy. The ISO 9001 certification of the research institute underlines its quality, competence, and performance.

High-performance 2-axis tilting mirrors from Fraunhofer IPMS

A development of the Dresden Research Institute is the technology platform of a CMOS-integrated micromirror array in which each mirror can be individually deflected via two tilting axes. The device consists of 512 x 320 individually addressable mirrors with a pixel size of 48μm and enables the redirection of light beams or the generation and control of 2D intensity profiles and patterns with variable intensity. Because light is redistributed rather than masked, a high light yield is possible.

Piston micromirror arrays for 3D holography

A completely new field of application for the piston micromirrors of Fraunhofer IPMS is holography. In contrast to alternative methods such as stereo projection, holographic projection allows the virtual representation of objects with a 3D experience identical to that of real objects.

Micromirror arrays from Fraunhofer IPMS will enable computer-generated holography in the future. Real and virtual worlds merge – in motion and in real time. A mirror matrix optimised for holography is currently under development. The first application scenario is a head-up display (HUD) for automobiles.

At the Photonix exhibition in Japan from October 4 to 6, visitors can see the latest developments of Fraunhofer IPMS. A 2-axis tilting mirror demonstrator will be presented. In addition, the technology of spatial light modulators will be explained using macro models. The Fraunhofer IPMS booth is located at the Makuhari Messe (Chiba, Tokyo Area) in hall 8 booth #49-10. Appointments for expert talks with scientists and developers can be made in advance via the Fraunhofer IPMS website.