Optical microsystems from Fraunhofer IPMS

Fraunhofer IPMS develops spatial light modulators with up to several million mirrors on a semiconductor chip. Depending on the application, the micromirrors are individually tilted or lowered to create surface patterns, for example to produce defined structures. The spatial light modulators are used in particular in microlithography in the deep ultraviolet range, in PCB production, semiconductor inspection and measurement technology as well as in adaptive optics, astronomy, holography and microscopy. With its developments in this field, Fraunhofer IPMS is a world leader.

A development of Fraunhofer IPMS is a CMOS-integrated micromirror array with two tilting axes per mirror and a corresponding technology platform. The device consists of 512 x 320 individually addressable mirrors with a pixel size of 48 μm.

The optical principle is based on spatially resolved redistribution of light. This can be used to redirect light beams or to create and control 2D intensity profiles and patterns with variable intensity. Because light is redistributed rather than masked, higher light output is possible. This innovation opens up new possibilities in the semiconductor industry, microscopy, especially for biomedical applications, and laser materials processing (laser ablation, engraving).

Another SLM technology of Fraunhofer IPMS is a matrix component with about one million micromirrors with an optically active area of 33 x 8mm². The matrix can be reprogrammed with a frequency of 2kHz, whereby each torsional mirror is provided with an individual deflection. Based on this device configuration, application-specific customer requirements can be taken into account for further development. A Customer Evaluation Kit is available for customers to explore new applications. The kit consists of a matrix of 256 x 256 individual mirrors (64k), control electronics and software. A current development at the institute is to implement piston mirrors on the 64k platform.

At LASER World of PHOTONICS in Munich, visitors can examine the latest developments of Fraunhofer IPMS from 27th to 30th June. One exhibit is a 2-axis tilting mirror demonstrator. Visitors will also be introduced to the technology of spatial light modulators using macro models.