Fabrication of Flat-Top Interleaver and Add/Drop Filter Modules in Dense Wavelength Division Multiplexing System

• Main Authors: Chao-Shing Hsieh, 謝昭行
• Other Authors: Wood-Hi Cheng
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/30065212956007266384

博士 === 國立中山大學 === 光電工程研究所 === 91 === In this dissertation, we study the fabrication and performance of fiber coupler, add/drop filter module, and flat-top interleaver for use in dense wavelength division multiplexing (DWDM) systems. In the low loss fused biconical taper coupler (FBTC), an optimum approach for fabrication of FBTC is a lower filament speed, a higher gas flow rate, and a longer pulling length. By applying this optimum approach that the FBTCs with low loss of 0.13 dB and small taper angle of 20o have been fabricated successfully. In the add/drop filter module, the module-insertion loss difference (0.3 dB) and angular tilt misalignment (0.05o) are found after undergoing 42 temperature cycles for the imperfect soldering process. We present our experimental results of a flat-top 50 GHz optical interleaver using two Gires-Tournois Etalons (GTEs) as phase dispersive mirrors in a Michelson interferometer. The spectral characteristics of the interleaver in a 50 GHz channel spacing application exhibit a 0.5 dB passband larger than 43.8 GHz (88% of the spacing), a 25 dB stopband greater than 40 GHz (80% of the spacing), and a channel isolation higher than 35 dB. The result shows that the interleaver interferometer with novel GTE technique can simultaneously produce a 0.5 dB passband and a 25 dB stopband wider than other interferometer techniques.