The area of micro-optics covers a variety of techniques used for developing miniaturized optical components and systems for applications ranging from optical communications and information processing and storage, to biomedical instrumentation and lightwave sensing and imaging. Miniaturization of optical devices and components is of great interest for system designers for many reasons. A reduction in the total volume of the components is not only cost-saving but sometimes necessary when space or portability is of concern. The trend of micro-optics is toward a higher degree of integration that provides enhanced stabiiity (and thus performance) in addition to the compactness in the construction of complex systems.
This dissertation discusses micro-optics at two levels; the first part contains our works on monolithic-cavity, passively mode-locked semiconductor lasers, which are micro-optical devices that can generate millimeter-wave signals with configuration as simply as that for CW lasers. The dynamics of passive modelocking and the transient phenomena when the laser is switched "into" and "out of' modelocking have been studied both experimentally and theoretically. The observation of doubling in the passive modelocking frequency under certain operating conditions is also described. The modelocking characteristics, such as the tunability of modelocking frequencies and the mode-locked RF signal linewidths, under different ambient temperatures (down to the liquid-nitrogen temperature) are also measured and analyzed in the laboratory and compared with theoretical predictions.
The second part of the thesis deals with micro-optics at a higher level, describing our approach to integrating optical components and (sub)systems using silicon micromachining technologies. Taking advantage of the batch-fabrication feature akin to IC-processing and the capability of mechanical and electronic integration, these microphotonic systems are compact, lightweight, and potentially very inexpensive. The applications of microphotonics covered in this dissertation include external-cavity (mode-locked) semiconductor lasers, optical scanner for laser scanning and displays, and passive optomechanical components for communication systems.
April 30, 1998
Kiang, M. (1997). Micro-optical Devices for Communications and Beyond: The Days Before and After Silicon Micromachining. United States: University of California, Berkeley.