Bidirectional Microdisplay (OLED on CMOS)

For the first time ever, OLEDs and OLED-on-CMOS integration offer the possibility to integrate highly efficient light sources with photo detectors on a single CMOS chip. This enables monolithically integrated optoelectronic applications based on standard silicon. Besides classic optoelectronic sensor applications, this also enables innovative solutions for personalized information systems. One of them is the so called Bidirectional Microdisplay, i.e. an element that displays an image and acts as a camera at the same time by interleaving display pixels and photo detectors in a mosaic style. This allows to provide visual information to the user, at the same time the device is capable of sensing eye movements of the user. Using some sort of modified eyeglasses the user will perceive the environment the usual way, additional optical information will be provided using the information system (Augmented Reality). This information may be adapted to the overall context. Without using the hands or spoken commands the user can control the presented information just with movement of the eyes. This microdisplay as a result of the BMBF funded project “ZOOM” has attracted worldwide attention. Therefore the scientists enter now new applications in a project (called “ISEMO”, also funded by BMBF), which has been started end of 2008. Here the OLED microdisplay is projecting a controlled pattern onto an object surface (via prefixed optics), while the embedded camera observes the disortion of the light pattern being caused by the object's topography. The resulting image pattern is used to calculate the object's surface shape. So the new technology can lead directly to complete new innovative products, as e.g. miniaturized, integrable deflectrometric sensors for the characterization of surfaces (finish and shape).

We thank the Federal Ministry for Education and Research BMBF for funding the projects ZOOM and ISEMO under contract 16SV2283 and 16SV3682.