| Lightwave plays an increasingly important role in communication. In order to break through the limitation of "electronic bottle neck", the development of all-optic communication network and key optical devices are indispensable. Optical switch and variable optical attenuator (VOA) are two of key components. Optical switch can be used for Optical Cross Communication (OXC) and Optical Add or Drop Multiplexing (OADM) in the node of networks. Variable optical attenuator is an important component in optical networks, providing gain equalization in optical amplifiers, signal attenuation for detector saturation protection, as well as power management for varying numbers of active channels. This dissertation studies the non-silicon based micro-machining optical switch and variable optical attenuator.The content of the dissertation is separated into two parts. One is the research of non-silicon based micro-machining optical switch and the other is the research of non-silicon based micro-machining variable optical attenuator. We studied these two devices from theoretical design and experiments.In the first part, we reported a low-cost non-silicon based fiber optic switch featuring a novel design of reflection cell, which is capable of ±5 V pulse operation and self-latching. The switch prototypes were measured to have a switch time less than 2 ms, return loss of 50 dB and low insertion loss. Enabling technology is Electrical Discharge Machining. The dynamic process of switching was analyzed using an FEA software ANSYS for design optimization. A reasonable agreement was observed between the measurement and simulation results. The switch is scalable to 4x4 or above and allows the realization of high capacity cross-connects. This project has passed Economic & Trade Commission appraisal.In order to match the assembly needs of optical switch arrays, we developed an alignment apparatus for fiber collimator array. The apparatus has six freedom of motion, one rotating round the optical axis of the collimator, two orthogonal oscillation around the exit point, and three orthogonal translational motion. The deviation between the axis of collimator axis and the rotation axis of oscillation is also eliminated. It has been granted Chinese patent.In the second part, a novel micro-machining based digital variable optical attenuator is developed. The design of the VOA was optimized to achieve a linear response and digitalizedvariation of attenuation. The characteristics of the device were analyzed with a scalar wave theory based numerical simulation. The performance test of the device showed a low insertion loss(0.5dB), low wave dependent loss(0.2dB), high return loss(>50dB), and wide dynamic response(0~40dB). It has been granted Chinese patent.A non-silicon micro-machining based 512-step fast digital VOA was designed and characterized in the last part of Sec.2. The device locates nine attenuating micro-filters in the beam path, with 0.1dB, 0.2dB, 0.4dB, 0.8dB, 1.6dB, 3.2dB, 6.4dB, 12.8dB,25.6dB attenuation respectively, and controls the states of a specified filter or some specified filters through digital control circuit, according to binary encoding conception, to achieve precise stepwise attenuations(0.1 dB). It offers a fast response time(less-than 1.9ms), low insertion loss(0.37dB), small wave dependent loss(0.2dB), and wide dynamic response(0~50dB). It has been applied for Chinese patent.A novel non-silicon based variable optical attenuator was reported at last. The VOA is comprised of an EDM micro-machined structure, in which a micro mirror is driven electro-magnetically to adjust for desired attenuation continuously.
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