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Showing 1 to 18 of 18 for “"Induced birefringence"”.
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Photo-induced birefringence in single-mode optical fiber
… wide bandwidth, small size, and light weight. Birefringence is an important parameter of the optical fiber, determining bandwidth in fiber optic telecommunications, and resolution in fiber optic sensors. This thesis describes and demonstrates permanent photo-induced rotation of the principal …
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A Photo-Electric Method for Detecting Acoustically Induced Birefringence in Liquids
Made available in DSpace on 2014-12-10T19:06:50Z (GMT). No. of bitstreams: 1 7212078.pdf: 4647154 bytes, checksum: f7c5a413ffc38e4633ba37a051d3821b (MD5) Previous issue date: 1971
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Spatially resolved measurements of kinematics and flow-induced birefringence in worm-like micellar solutions undergoing high rate deformations
… to measure the flow kinematics and a commercial birefringence microscopy instrument (ABRIOTM System, CRi., Inc.) was adapted for making full-field measurements of flow-induced birefringence (FIB) in order to obtain high-resolution measurements of the evolution of the average stress and molecular …
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Constitutive modelling of branched polymer melts in non-linear response
… model is compared to experimental flow induced birefringence images. It is shown for linear and lightly branched materials that the Pompom model predicts both the form of the birefringence pattern and stress values obtained from the stress-optical law. However, for more highly branched …
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Current profile measurements using MSE on Alcator C-Mod
… polarization measurements due to thermal-stress induced birefringence; and (3) the measurement of current density profiles in Lower Hybrid Current Drive (LHCD) experiments. The major hardware upgrades include replacement of photomultiplier tubes (PMT's) with avalanche photodiodes (APD's) which …
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Study of artificially disordered optical fibers
… glasses. Secondly, it is shown that induced birefringence is insufficient to explain mode mixing, and that cross-polarization mode coupling is essential. Such a coupling is shown to originate from the spatial correlation in the off-diagonal elements of the dielectric tensor. Third, a …
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Development of high power fibre amplifier components, systems and applications
… the rotators to compensate for thermal stress induced birefringence. Using this approach the isolation was shown to be constant to greater than 60W. The isolator was also compensated for thermal lensing by balancing the positive thermal lens produced in the Faraday rotator with a negative …
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Kerr electro-optic measurements for electric field and space charge distributions using similar and dissimilar electrode pairs
… effect, an electro-optic method based on field-induced birefringence, is used to measure the electric field and space charge distributions between a pair of high voltage stressed identical or different metal electrodes. The non-uniformities in the electric field can then be mapped to determine …
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Powers scaling and nonlinear frequency conversion of single-frequency lasers based
… related problems such as thermal lensing, stress-induced birefringence and stress induced laser rod fracture. Also a passive technique for mode-hopping-suppression is described, allowing the oscillating frequency within the laser cavity to tune over many axial mode spacings before a mode-hop …
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Transient electric birefringence of macromolecular systems
The transient electric birefringence method, i. e. the transient Kerr effect, has been employed to study the optical, electrical and geometrical properties of three macromolecular systems. An apparatus is described in which the birefringence could be measured when d. c. electric field pulses (of …
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Bangolaidžių integravimas į lydytą kvarcą panaudojant femtosekundinius šviesos impulsus /
… formation of nanogratings, responsible for induced birefringence.
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The Synthesis, Characterisation and Electro-Optical Properties of Polypentenylene-Block-Co-Acetylene
… for the simultaneous measurement of electrically induced birefringence and electrically induced dichroism. This technique was used to determine the electric birefringence and dichroism of solutions of polypentenylene-block-co-acetylene in cyclohexane. The results indicated that the copolymer …
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Investigation of Bragg Gratings in Few-Mode Fibers with a Femtosecond Laser Point-by-Point Technique
… knowledge. To highlight, we report the laser-induced birefringence exhibits strong offset dependence, the reflectivity heavily depends on the offset and polarization, and particularly the mode pattern can be controlled solely through polarization. The design and characterization of cross-axis …
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The Flexoelectro-optic Effect for Photonics Applications
… of up to 6.8 V/μm are shown to induce a maximum birefringence of ∆n=0.037, due to both flexoelectric and dielectric coupling, and ∆n=0.012 due to flexoelectric coupling only in a sample based on symmetric difluorinated bimesogens. This induced birefringence is shown to consistently respond to …
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Engineering upgrades to the Motional Stark Effect diagnostic on Alcator C-Mod
… This system was used to identify thermal-stress induced birefringence in several of the diagnostic's lenses as the cause of polarization calibration drift. Gold-plated radiative heat-shields and low-conduction lens and periscope mounts thermally isolate the in-vacuum periscope, and a forced-flow …
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Quantitative Anisotropy Imaging based on Spectral Interferometry
… advantage. In this work, a dual-modality phase/birefringence imaging system is proposed to offer a quantitative approach to characterize phase, polarization and spectroscopy properties on a variety of samples. An interferometric spectral multiplexing method is firstly introduced by generating …
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Nonlinear Light - Matter Interactions of Ultrafast High Intensity Laser Pulses
… effects of extreme optical intensities on Kerr induced birefringence in CS<sub>2</sub>. At high input intensities, the material will act similar to a waveplate and can create multiple phase rotations in a probing beam. This effect can be studied by looking at the oscillatory structure it forms …
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Experimental and theoretical analysis of polarization-maintaining fibre for sensing applications
… for a range of industrial applications. High-birefringence (Hi-Bi) optical fibres represent an important type of specialist fibres that have been explored widely by researchers. The focus of this thesis is to explore their potential for different sensing applications as the birefringence of …