Electromagnetically Actuated Devices For Optical Coherence Tomography Applications

Abstract

A fast optical scanning device has always been desired for numerous applications such as biomedical imaging, optical communications, and variety of sensing and actuating applications. This dissertation presents a new scanning device operated using external magnetic field with low cost, high function versatility, low field strength, and low power consumption. The design architecture of this device shows its potential for in vivo application with an advantage that addresses the concern of safety. Materials properties are examined using alternating gradient magnetometer(AGM) to verify its performance. Pressure and temperature invariant fabrication processes are implemented to make this device without complicated equipments. The development and construction is discussed from materials and device performance properties. In this dissertation, the device is also explored from the endoscopic point of view for in vivo imaging: device functionalities and its constraints as an endoscopic scanner. Preliminary static and dynamic performance data are shown to demonstrate its ability as an optical scanner with compromising speed and scanning range. To test for its applicability in imaging application, the device is made compatible with an optical imaging system, namely, optical coherence tomography ( OCT ). OCT is a relatively new imaging modality capable of cross sectional imaging with resolution in micrometers. The setup used to test the optical scanner is an OCT system which retrieves information about the depth resolved reflectivity profile using the spectral domain information of the reflective light. This report is started with a review of magnetics, which explains the fundamental governing principles behind the optical scanner. In the second section technical information about the optical scanner is entailed. Finally, the investigation on the suitability of the scanner for OCT application is performed.