Summary: | 碩士 === 國立臺灣大學 === 光電工程學研究所 === 96 === We are witnessing a new era that signal transmission in short range is being replaced from electronic ones by optical ones. Optical waveguides for short-range transmission could be made below one micrometer in diameter. The transmission loss is one of the key concerns for practical applications. Among all the loss factors, the surface roughness of the micro or nano waveguide is the major one. Our research group utilized a new fiber drawing process based on the traditional fiber drawing tower to obtain a micro fiber below one micrometer in diameter from a standard single mode fiber. The microfiber inhered smooth surface finish. With proper control by using a tungsten tip to operate over a silicon substrate, a micro ring resonator could be formed. Moreover, taking advantage of lithography process, we could make patterns of photoresist on the silicon wafer. After the molding of PDMS, we could have the patterned PDMS substrate. With such a developed manipulation method, we could put the micro fiber into the patterned slot. Furthermore, we could use the evanescent wave coupling scheme to couple light into the micro ring resonator and measured its transmission spectrum. As compared with existing theories, we could get the transmission coefficient, the round trip attenuation factor and coupling loss of the micro ring . The measured resonance transmission loss was up to 7dB
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