INVESTIGATION OF PERIODICALLY SEGMENTED WAVEGUIDES IN ION-EXCHANGED GLASS FOR INTEGRATED OPTICS APPLICATIONS

• Main Authors: Yen-Juei Lin, 林晏瑞
• Other Authors: Woo-Hu Tasi
• Format: Others
• Language: en_US
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/30581901539783900168

碩士 === 大同工學院 === 電機工程研究所 === 87 === ABSTRACT In this thesis, the K+-Na+ ion-exchanged technique is used to fabricate several periodically segmented waveguide (PSW) structures with different periods and duty cycles in soda-lime glasses. This technique has the advantages such as simple treatment, low loss and low cost, also has very high performance for the channel waveguide to fiber coupling due to very small refractive index difference between the glass and the fiber materials. Both theoretical analysis and experimental measurement has been carried out for the comparison. In this thesis, the near-field (NF) method is applied to the index profile measurement. However, there exist noise problem. We propose the use of variation method to smooth the measured intensity profile without complexity or loss of accuracy. A new trial field, namely, the modified Hermite-Gauss (MHG) function has been used. We have coupled laser beam (at 0.6328 wavelength) into PSW by virtue of the end-fire coupling method, and have also verified the theories of PSW. Agreement between the m-line method area and the NF-method area could be as good as 95%. The model has been proved to describe the behavior of PSW successfully. Agreement between the model and the experimental results could be as good as 98%, which indicates that the properties of PSW in ion-exchanged glass with the same accuracy. We also get the experimental results that mode size widens as the duty-cycle decreases but is independent of the period. There is self consistency between the theoretical calculation and the experimental measurement.