Measuring the Footprint of Cells (1/2) (IMAGE) Fraunhofer-Gesellschaft Caption The sensor is covered with 250,000 tiny plastic columns only five microns in diameter. When a cell creeps across the tips of the columns, it presses each column very slightly sideways. Credit Fraunhofer IFAM Usage Restrictions The picture may be used for editorial purposes only. It is protected by copyright. The use is free of charge if the reference is mentioned. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.