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Biocompatible optical waveguides receive increasing attention owing to their application potential in the biomedical field. Our focus is on the fabrication and characterization of a new step-index biodegradable polymer optical fiber (bioPOF) using two commercial polyesters: poly(D,L-lactic-co-glycolic acid) (PDLGA) and poly(D,L-lactic acid) (PDLLA). Both polymers are regulated by US FDA, which allows projecting future clinical use of fibers made from these materials. We manufactured three preforms and we subsequently drew optical fibers with a standard heat-draw tower. We describe the chemical properties of the materials throughout the whole production chain from polymer granulates to preforms and then to optical fibers. We look into to the influence of the processing on the molecular weight and thermal characteristics of the polymers. Our step-index bioPOF with an outer diameter of 1000 ± 50 μm and a core of around 570 ±30 μm features record low attenuation of 0.26 dB•cm at 950 nm for step index bioPOF, and a numerical aperture of 0.163. Immersion in phosphate-buffered saline (PBS) leads to hydrolytic degradation of the bioPOFs over a period of 3 months, accompanied with a 91% molecular weight loss. From the degradation study results, we anticipate that our bioPOFs can be used for biophotonic applications requiring deep tissue light delivery, such as photodynamic therapy.

We demonstrate a biodegradable and biocompatible unclad optical fiber made from poly(D,L-lactic acid) (PDLLA), which is a well-known and commercially available amorphous polyester. We first deal with the chemical and optical characterization of the bulk polymer material and we report on the influence of the processing on the molecular weight and thermal properties of the polymer, during both the preform preparation and the fiber drawing process. We then proceed to the optical characterization based on spectral attenuation measurements using the cutback method and dispersion measurements. We also determine the thermo-optic coefficient. Finally, we confirm the in vitro degradation in phosphate buffered saline (PBS) of our PDLLA fibers. From the results and considering that PDLLA is an FDA-regulated material, we anticipate that our optical fibers are valid candidates for medical applications involving in vivo light delivery, such as for example photodynamic therapy.

In this paper we have been experimentally investigated ther mo-optic properties of a Co nanofluid filled mictrostructured fiber (MSF). We have prepared samples based on pure chemical compounds: cyklohexane and toluene and both of them were used as solvents for Co nanoparticles. MSF filled by cyklohexane and its mixture with Co nanoparticles worked on weakly guided regime and toluene based MSFs samples became the solid core bandgap fibers. We have measured temperature transmission spectral characteristics within the range of 18 o C – 80 o C. Temperature sensitivity of Co nanofluid based on cyklohexane were the strongest in third telecommunication window and reached 0.12dB/ o C with dynamic range of 7dB. For toluene based samples we observed bandgaps shifts from the longer to the shorter wavelengths. Temperature sensitivity of thes e type of samples were close to -5nm/ o C. Keywords : microstructured fiber, photonic crystal fiber, microstructured fiber filling technology, Co nanoparticles, Co nanofluid, thermo-optic effect.

The idea and realization of data presentation system is described in this paper. Data is received from the diagnostic system of the BAC detector. The presented system is a part of the DQMS (Data Quality Monitoring and Management). The system enables graphical presentation of the location of electronic blocks. It is possible to indicate the links between these blocks, and the actual state of the specified components. The aim to build this system was to assure the proper working of the BAC detector, and in the case of detecting abnormalities to find them out as soon as possible, detect the place of the error and the causes of the failure. The presented software helps to find the errors and is a sort of knowledge compendium about the BAC detector (its equipment, links structure, etc.). The engineering of the visualization system as well as functional tasks were described, and the discussion of the results was made. Some examples, showing the usage of the system, and the received results of its work were presented.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The paper presents functional structure of database system of data measurement quality for BAC detector in ZEUS experiment. The system collects diagnostic and experimental data. Diagnostic data are: work parameters of the detector and electronics/photonics, tests of electronic/photonic blocks. These data are archived for certain period of time. The quality of current data collection process is estimated using these archived data. The result of such estimation is generated in a form of status map of the detector. Such maps, describing status of the hardware, are fundamental for elementary particle analysis by the calorimeter. The DAQ system, collecting data to the database, estimates data quality on-line during transmission and writing. This mechanism of fast on-line data quality management leads to early discoveries of detector work irregularities and faults.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.