Microstructured fiber

Nagahara, T., Imura, K. and Okamoto, H. (2004) Time-resolved scanning near-field optical microscopy with supercontinuum light pulses generated in microstructure fiber. Rev. Sci. Instrum., 75, 4528-4533. 

By launching femtosecond pulses from a mode-locked Ti Sapphire laser into an appropriate microstructured fiber, one can generate a supercontinuum output spanning from the blue to the near... 

Tada, J., Kono, T., Suda, A., Mizuno, H., Miyawaki, A., Midorikawa, K., and Kannari, F. 2007. Adaptively controlled supercontinuum pulse from a microstructure fiber for two-photon excited fluorescence microscopy. Appl. Opt. 46(15) 3023-30. 

Ouzounov, D.G., K.D. Moll, M.A. Foster, W.R. Zipfel, W.W. Webb, and A.L. Gaeta. 2002. Delivery of nanojoule femtosecond pulses through large-core microstructured fibers. Opt. Lett. 27 1513-1515. 

Fig. 2 Various types of hollow-core photonic bandgap fibers, (a) Photonic crystal fiber featuring small hollow core surrounded by a periodic array of large air holes, (b) Microstructured fiber featuring medium-sized hollow core surrounded by several rings of small air holes separated by nano-size bridges, (c) Bragg fiber featuring large hollow core surrounded by a periodic sequence of high and low refractive index layers...

A major limitation of the sensitivity of this type of sensor is the ability to transfer optical power into the evanescent field. Recent work has incorporated new types of fibers to increase the sensitivity of measurements. Newly developed hollow core fibers, which guide light mainly in the cladding, can be used to couple more power into the sensitive materials [76]. If the hollow core fiber is used as the active sensing area between two silica core fibers, then the transitions between the fibers will force the light to travel from the core into the cladding then back into the core. Another type of fiber is the microstructure fiber or photonic crystal fiber, which incorporates air holes into... 

Pagnoux, D. et al. Microstructured fibers for sensing applications. 17th Int. Conf. on Optical Fibre Sensors (OFS-17), Bruges, Belgium, SPIE-Vol. 5855 (2005), pp. 5-8... 

Figure 2.3 (a) A microstractured conductive fiber contaming multiple bismuth-tin microwires. The inset is a magnified picture of a Bi-Sn wire, (b) Microstructured fiber capacitors with... 

Silica capillary microreactor/silica microstructured fiber... 

Bise R., Trevor D.J., Monberg E., Dimarcello F. Impact of preform fabrication and fiber draw on the optical properties of microstructured fibers. In Proceedings International Wide Cable Symposium Proceedings 2002 51 339-343... 

Microstructured fibers are usually fabricated by the stack-and-draw technique. Glassy capillaries are stacked and inserted into a jacketing tube to form a preform, which is then drawn. This step can be repeated to obtain target dimensions in the final fiber geometry. Alternatively, El-Amraoui et al. have recently prepared preforms with a variety of geometrical patterns by direct mechanical drilling of holes in the ChG rod [156]. 

Troles J., Brilland L., Smektala F, Houizot R, Desevedavy R, Coulombier Q., Traynor N., Chartier T., Nguyen T. N., Adam J. L., and Renversez G., Chalcogenide microstructured fibers for infrared systems, elaboration modelization, and characterization. Fiber Integrated. Opt, 28, 11-26 (2009). 

As the basic fiber microstructure is determined during the spinning and drawing processes, several spinning process variables have a significant impact on fiber properties e.g., flow rate, winder speed, spinnerette geometry, etc.). Spinning... 

Chou, T.W. (1992) Microstructural Design of Fiber Composites (Cambridge University Press. Cambridge). 

Figure 1 Schematic representation of the microstructure and cross-sectional view of a liquid crystEilline copolyester fiber [33].

PET fibers in final form are semi-crystalline polymeric objects of an axial orientation of structural elements, characterized by the rotational symmetry of their location in relation to the geometrical axis of the fiber. The semi-crystalline character manifests itself in the occurrence of three qualitatively different polymeric phases crystalline phase, intermediate phase (the so-called mes-ophase), and amorphous phase. When considering the fine structure, attention should be paid to its three fundamental aspects morphological structure, in other words, super- or suprastructure microstructure and preferred orientation. 

Characteristic of the microstructure of PET fibers in their final production form is the occurrence of three types of polymer phases crystalline, mesomorphous, and amorphous. The first phase is the result of crystalline aggregation of PET molecules, the second phase—of mesomorphous or, in other words, paracrys-talline aggregation, the third phase—of amorphous aggregation. The mesomorphous and amorphous phases together form a noncrystalline part of the fiber. 

The amorphous orientation is considered a very important parameter of the microstructure of the fiber. It has a quantitative and qualitative effect on the fiber de-formability when mechanical forces are involved. It significantly influences the fatigue strength and sorptive properties (water, dyes), as well as transport phenomena inside the fiber (migration of electric charge carriers, diffusion of liquid). The importance of the amorphous phase makes its quantification essential. Indirect and direct methods currently are used for the quantitative assessment of the amorphous phase. 

Comparing the alteration in a values with the established changes in fine structure parameters presented in Table 12, it can be seen that the alteration in a values does not correlate with variations in any particular structure parameter. This leads to the conclusion that the ascertained alternation in a must be evoked by a complex change in different substructure, microstructure, and orientation parameters of the fiber. 

Bulk microstructure Continuous channels Between fibers Complex foam to vertically oriented channels Closed cell to open cell foam None... 

Microscopic techniques are extensively used to study the surface morphology of reinforcing fibers. The characterization of microstructure of polymer fibers provides an insight into stmcture-property relationship of the fiber. Microscopy techniques have been employed for the... 

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