People > Dennis M. Freeman > Biographical Background

Biographical Background

Professor Dennis M. Freeman is a principal investigator in the Research Laboratory of Electronics (RLE) at the Massachusetts Institute of Technology (MIT). He received his B.S. from the Pennsylvania State University in 1973, and his S.M. and Ph.D. in electrical engineering from MIT in 1976 and 1986 respectively.

Professor Freeman pioneered a new optical paradigm for semiconductor critical dimension (CD) metrology called Synthetic Aperture Metrology (SAM). SAM combines the speed of optical methods with the microscope imaging capability of CD scanning electron microscopy (CD-SEM).

Professor Freeman also is involved in developing instrumentation that visualizes the microscopic motion of biological and synthetic structures. His research in this area is aimed at determining how biological transducers -- membrane-bound proteins called ion-channels to perform transduction processes -- components are organized into a system: the inner ear. Professor Freeman has developed a video-based technique that measures sound induced motions of the inner-ear structures, and is now extending this method to other biomedical and engineering applications. Understanding the signal processing techniques used by sensory cells in the inner ear holds promise to inspire new engineering strategies, including the possibility of designing man-made systems that exploit cellular components.