Novel theoretical formulations and efficient simulation methods for polarization-mode dispersion (PMD) and polarization-dependent loss (PDL) that are directly applicable to optical network design are developed. In particular, a formalism based upon the Magnus expansion is advanced for the determination of the frequency evolution of the Mueller matrix in terms of increasing orders of PMD and PDL. Several previous models of polarization evolution are shown to be specializations of this more general formalism. A least-squares algorithm that extracts PMD and PDL coefficients from repeated measurements of the output Stokes vector of an optical system for a random set of input polarization states is introduced and subsequently applied to the rapid experimental determination of the probability density of the differential group delay of a fiber-squeezer based PMD emulator. The applicability of Clifford algebra and Pade-approximant techniques to the efficient simulation of the wavelength dependence of PMD and PDL is also discussed.

The present study developed a new ¡V typed Photobioreactor, ¡§ Automatically Temperature Controllable and Wave-Mixed Photobioreactor System, ATCWPS ¡§ . The main propose of the study is to reduce the energy consumption and production cost during the process of cultivation. It can be cut down the over-dependent of nature resource on the land and expand the ocean by using the advantage of the nature marine environment. The Photobioreactor based on baffled tanks is investigated and the effect of the displacement of the Photobioreactor induced by external waves on liquid sloshing is discussed. The vortices generated by baffles can mix the fluid in the Photobioreactor. The influence of water depths and baffle height can be utilized to develop the model of Photobioreactor by simulating the inner change of energy, and to decrease the temperature of Photobioreactor with the characteristic of seawater specific heat. The problem of non-averaged light in the system by optical fiber system of total internal refraction is also improved in this work. The result of the experiment made in the Shi-Hzuwan ( Bay ) aquaculture site shows the average temperature of algae liquid can be declined about 20%. The results of vibrating platform cultivation shows the baffled system can increase the energy of mixing micro-algae in the growing process. Optical fiber system of total internal refraction can enhance the light efficiency, and thus not only can improve the shading effect among algae, but speed up its growing rate. When the staggered baffles and the optical fiber system of total internal refraction are combined, the optimal result of the growth rate of algae can be obtained in this work.

Nonlinear optical microscopy (NLOM) utilizing femtosecond laser pulses is well suited for imaging living tissues. This work reports on the design and development of an optical fiber based multispectral NLOM developed around a laser generating broadband sub-10-fs pulses. An all-mirror dispersion-compensation setup is used to correct for quadratic and cubic phase distortions induced within the NLOM. Mouse tail tendon was used to characterize sub-10-fs pulses by interferometric autocorrelation. This is an effective method for characterizing dispersion from the optical system, immersion medium, and wet biological sample. The generation of very short autocorrelations demonstrates the ability to compensate for phase distortions within the imaging system and efficient second-harmonic upconversion of the ultrashort pulse spectrum within collagen. Reconstruction of ultrashort pulses at the focal plane of the objective allows the excitation of multiple fluorescent probes simultaneously. Multiple fluorescent probe excitation and spectral discrimination is demonstrated using mixtures of fluorescent dye solutions and an in-vitro angiogenesis model containing human umbilical vein endothelial cells (HUVEC’s) expressing multiple fluorescent proteins. Sub-10-fs pulses can be propagated through polarization-maintaining single mode fiber (PMF) for use in NLOM. We demonstrate delivery of near transform-limited, 1 nJ pulses from a Ti:Al2O3 oscillator via PMF to the NLOM focal plane while maintaining 120 nm of bandwidth. Negative group delay dispersion (GDD) introduced to pre-compensate normal dispersion of the optical fiber and microscope optics ensured linear pulse propagation through the PMF. Nonlinear excitation of multiple fluorophores simultaneously and polarization sensitive NLOM imaging using second harmonic generation in collagen was demonstrated using PMF delivered pulses. Two-photon excited fluorescence spectra and second harmonic images taken with and without the fiber indicates that the fiber based system is capable of generating optical signals that are within a factor of two to three of our traditional NLOM.

Along with the rising and flourishing development of the modern technology and human knowledge, the demands for optical-electric products and communication systems are getting more and more. By combining the semi-conductor technology process with micro optical elements, a complete micro optical system can be integrated. The functions of a micro optical system include beam-splitting, beam-light offsetting, focusing, and switching, etc. Letting micro optical elements be integrated on a substrate, the fix and alignment problems, which are caused by the relative displacements between the elements, can be improved. Also, the production rate can be increased and cost can be reduced if the products are made by micro mold and array fabricated process. Thus, the technology of the Micro Optical Electro Mechanical System is widely applied to manufacture the products of optical-electric and communication, such as the backlight module of a LCD, projector, and optical fiber communication system, etc. The main purpose of this study is to design and fabricate a microball-lens array, and to apply it to couple optical fibers. The proposed product is a 3D micro-ball-lens array with vertical and non-vertical focus directions and better coupling efficiency. A v-groove is fabricated by using semi-conductor technology in order to fix the micro-ball-lens array and optical fiber such that an optical fiber switch coupling system can be obtained. The packaging of the optical fiber switch coupling system is formed by UV-cure and a microcap which is fabricated by MEMS. It can provide the protection to the system. Also, the completed system can achieve the demands of the industry fields such as precise localization, cost reduction and so on.

Take the Quadrangular-Pyramid-Shaped Fiber Endface(QPSFE) and the Conical-Wedge-Shaped Fiber Endface(CWSFE) for example, the present procedure of grinding asymmetric optical fiber endface demands three to four steps. These steps take time and are lack of repeatability and high yield. Aim at the shortcomings, this study develops a set of mechanism to attach to the original optical fiber grinding machine. The mechanism makes the normal pressure between the endface and the grinding plate change periodically to modify the removing rate of the material, thus enables the clipped flat endface of the optical fiber be ground into an elliptic-cone-shaped in a single grinding step, and then becomes a lens after its tip being fused by the arc. This mechanism reduces the fabricating time and cost, and consequently improve the economic benefits as well by simplifying the complicated manufacturing processes that represented before. Besides, for its single-step grinding characteristic, the offset between the center of the fiber and the elliptic-cone can thus be slashed to promote the yield. This study reviews the anterior references, including the papers and the patents, to begin, and then proposes the current means to compare with. Its contents involve the development of the forming principle, which proposes how the variation of the normal pressure takes influence on the removing rate of the material, and the required mechanism for the design procedure. The mechanism, the research result, and those needed to be ameliorated will be demonstrated in the conclusion and discussion part, so as to offer the investigating direction in the future.

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The technique of the distributed fiber optic sensor system, the principle that we use Sagnac interferometer to sense time-varying physical field, can be used to measure the position of the disturbed physical field and have the ability of detecting continuous position. Based on the configuration of the Sagnac interferometer, sensing optic fiber is loop design, which is hard to be set in real surroundings, and a half length of loop fiber have to be the isolated protection of the physical field. Therefore, this essay brings up the In-Line conception to be the design direction. And we make use of the physical field of pipeline leak acoustic to detect disturbance position. The measurable range of systematic structure signal is 3¡Ñ10-4 ~ 3¡Ñ10-2 , and the dynamic range is 40 dB. On the other hand, the structure of polarization insensitive is brought up, the measurable range is 1.5¡Ñ10-3 ~ 3¡Ñ10-2 , and the dynamic range is 26 dB.

Abstract¡G Scalar coupled mode theory predicts that the output powers at two nonlaunch fibers are identical for the equilateral 3x3 fiber couplers due to the geometrical symmetry, but several experimental results demonstrate that they are not equal. In this work, a power coupling model with considering the polarization property of input power is proposed for the equilateral 3x3 fiber couplers. Consistent with the measurement results, the model shows that when a polarized light is launched into one of the three fibers the output powers at the other two nonlaunch fibers are unequal.

In this paper, the fesibility of using a Fiber Bragg Grating (FBG) as a sensing scheme to detect the underwater acoustic signals is analyzed. When a FBG is disturbed by an underwater sound, the wavelength of the FBG is changed. Therefore, the central spectrum of the reflected light is shifted according to the wavelength change of the FBG. This spectrum can be detected by an imbalanced two-arm interferometer. Its transfer function will be studied. Also, the polarization induced signal fading of those two-arm interferometers will be studied.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 88-91). Available also in a digital version from Dissertation Abstracts.