Bibliography: p. 215-231. / v, 231 p. ; ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis investigates the behaviour of semiconductor lasers under large amplitude sinusoidal current modulations. It focuses directly on the behaviour of Faby-Perot lasers under direct modulation of the injection current. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics and Mathematical Physics, 1999

Thesis (Ph.D.) -- University of Adelaide, Dept. of Physics and Mathematical Physics, 1999. / Bibliography: p. 215-231.

Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Kevin S. Repasky. Includes bibliographical references (leaves 61-62).

Thesis (Doctoral)--Technische Universiteit Delft, 1999. / Includes bibliographical references.

Thesis (Doctoral)--Technische Universiteit Delft, 1999. / Includes bibliographical references.

Thesis (M. Sc.)--University of Canterbury, 2009. / Typescript (photocopy). "August 3, 2009." Includes bibliographical references (leaves 87-90). Also available via the World Wide Web.

Bibliography: p. 215-231. This thesis investigates the behaviour of semiconductor lasers under large amplitude sinusoidal current modulations. It focuses directly on the behaviour of Faby-Perot lasers under direct modulation of the injection current.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 56-58). Also available via the Internet.

Fiber optic interferometric sensors have been used to measure a number of physical measurands like strain and temperature. Among the different interferometric sensor configurations in use today, the Fabry-Perot interferometer has been shown to have a high sensitivity. The extrinsic Fabry-Perot sensor (EFPI) is a very good candidate for smart structure applications. In this thesis, a new configuration of the extrinsic Fabry-Perot interferometer is developed and demonstrated. This new configuration, based on four-beam interference, utilizes two EFPI sensor heads on a single directional coupler in a Split-cavity Cross-coupled Extrinsic Fiber Interferometer (SCEFI) arrangement. This sensor configuration eliminates the need for biasing the phase difference at the quadrature point. The spectrum analysis scheme, devised for signal demodulation of the SCEFI output allows a linear readout of the phase shift. Both dynamic and static phase shifts are considered. The spectrum analysis scheme developed in this thesis, also allows independent measurements of the phase shift in the two sensor heads. This leads to the multiplexing of two sensors, using a single source and a single coupler. The application of the SCEFI to two-sensor multiplexing is demonstrated experimentally in this thesis. Other significant applications of this new sensor configuration are also discussed. / Master of Science

Este trabalho trata do desenvolvimento de um sistema de controle para um módulo do instrumento astronômico BTFI (Brazilian Tunable Filter Imager), um filtro óptico sintonizável altamente versátil que está instalado no telescópio SOAR, localizado no Chile. Será empregado neste instrumento um novo interferômetro Fabry-Perot, capaz de realizar observações em uma ampla faixa de resoluções espectrais. Para operar com resolução espectral variável, o Fabry-Perot proposto neste projeto terá uma faixa mais ampla de ajuste do vão entre suas placas refletivas, utilizando atuadores piezelétricos amplificados com grande capacidade de deslocamento e sensores capacitivos de alta precisão. O novo controlador apresenta uma malha de controle totalmente digital, implementada com um DSP (Digital Signal Processor) sintetizado num dispositivo FPGA (Field-programmable Gate Array). Na primeira etapa do desenvolvimento, trabalhou-se com um sistema de posicionamento nanométrico utilizando um protótipo simplificado com um canal composto por um sensor capacitivo de distância e um atuador piezelétrico. A partir dos bons resultados obtidos no sistema de um canal, realizou-se a expansão para um sistema de controle multi-malha de três canais com protótipo do Fabry-Perot, mas sem o uso das placas de vidro refletivas definitivas. O sistema permite controlar o posicionamento para cada canal individualmente ou os três em simultâneo, com desempenho adequado para os requisitos do filtro óptico sintonizável Fabry-Perot. / This work aims the development of a control system for a module of the BTFI astronomical instrument (Brazilian Tunable Filter Imager), a highly versatile optical tunable filter, deployed on the SOAR Telescope. The instrument will employ a new Fabry-Perot interferometer, which is able to provide observations in a wide range of spectral resolutions. In order to achieve variable spectral resolution, the new Fabry- Perot proposed in this project will present a larger range for adjusting the air gap between its reflective plates, using amplified piezoelectric actuators presenting high stroke capability and high precision capacitive sensors. The new controller presents a full digital control loop, implemented in a DSP (Digital Signal Processor) synthesized through a FPGA device (Field-programmable Gate Array). During the first phase of the development, it was used a nanometric positioning system using a single channel prototype comprising one capacitive sensor and one piezoelectric actuator. The good results obtained using the single channel prototype led to the expansion to a 3- channel multi-loop control system on a Fabry-Perot prototype which comprises dummy plates. The system allows controlling the position of each channel separately or simultaneously, presenting performance in accordance with the requirements of a Fabry-Perot optical tunable filter.