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Fiber optical interferometers belong to highly sensitive equipments that are able to measure slight changes like distortion of shape, temperature and electric field variation and etc. Their great advantage is that they are insensitive on ageing component, from which they are composed of. It is in virtue of herewith, that there are evaluated no changes in optical signal intensity but number interference fringes. To monitor the movement of persons, eventually to analyze the changes in state of motion we developed method based on analysis the dynamic changes in interferometric pattern. We have used Mach- Zehnder interferometer with conventional SM and PM fibers excited with the DFB laser at wavelength of 1550 nm. It was terminated with optical receiver containing InGaAs PIN photodiode. Its output was brought into measuring card module that performs on FFT of the received interferometer signal. The signal rises with the composition of two waves passing through single interferometer arm. The optical fiber SMF 28e or PM PANDA fiber in one arm is referential; the second one is positioned on measuring slab at dimensions of 1×2m. A movement of persons over the slab was monitored, signal processed with FFT and frequency spectra were evaluated. They rose owing to dynamic changes of interferometric pattern. The results reflect that the individual subjects passing through slab embody characteristic frequency spectra, which are individual for particular persons. The scope of measuring frequencies proceeded from zero to 10 kHz. At experiments the stability of interferometric patterns was evaluated as from time aspects, so from the view of repeated identical experiments. Two kinds of balls (tennis and ping-pong) were used to plot the repeatability measurements and the gained spectra at repeated drops of balls were compared. Those stroked upon the same place and from the same elevation and dispersion of the obtained frequency spectra was evaluated. These experiments were performed on the series of 20 repeated drops from highs of 0,5 and 1m. The evaluation of experiments displayed that the dispersion of measured values is lower than 4% and could be reduced by PM fibers usage.

Polyaniline hydrochloride was prepared by the oxidation of aniline hydrochloride with ammonium peroxodisulfate in dilute hydrochloric acid. The polyaniline films were produced during the polymerization on the microscope glass surfaces immersed in the reaction mixture. The thin film was created and its thickness has been about 100 nm. We have measured the spectral transmittance together with temperature changes. The polyaniline thin film is conductive and we observed changes in optical transmittance spectra and reflective spectra with electric current. Optical spectra have been measured in range from 380 nm to 1010 nm. The electric conductivity has been changed with silicate substrate. This substrate influenced the free electrons distribution and therefore the optical properties of polyaniline. Due to electric current going through the nanofilm its sensitivity to temperature has been increased. We also observed two specific spectral windows. The first one was characterized by its insensitivity to temperature; the second one has been temperature sensitive. The central wavelength of insensitive window is about 500nm. This property can be the base for novel sensors structures. We used Ocean Optics USB spectrometer for evaluation of spectral changes. Wideband white light halogen source from the same manufacturer has been applied as a light source. Small polarizing dependence of reflected light has been observed too.

The team of authors tries to provide information on the results of the fiber-optic DTS system application under long-term research of accumulation possibilities of thermal energy in the rock mass in this article. In 2006, was in Ostrava implemented the largest object in the Czech Republic, which is heated by heat pump system. It is a multi-purpose aula at VŠB-TU + CIT (Center for Information Technology). The installed heat pump system consists of ten heat pumps with a total output of 700kW and 110 wells about 140m deep. The applied research is conducted in two measuring polygons ("Big" and "Little" polygon). Simultaneously with fiber-optic DTS system is applied group of PT1000 temperature sensors and Geothermal Response Test (GERT). Fiber-optic DTS system is deployed inside polyethylene PE collector via a special sensory fiber optic cable. The ecological antifreeze mixture, based on the technical spirit, used for the collection and delivery of energy to the rock mass circulates inside of PE collector. PT1000 temperature sensors are placed at certain intervals on the outer side of the PE U-tube within the heat well. The result of application of the fiberoptic DTS system is information about the heat profile of wells, thermal conductivity of the geological environment and the impact of external changes in the thermal wells, along with the accumulation possibilities of thermal energy in the rock mass (over-summer period).

This article deals with spectral characteristics measurement of fiber couplers which are used for FTTx networks. Due to WDM systems we are able to communicate with several wavelengths at a time. In xPON systems the data transmission runs at wavelengths 1310 nm, 1490 and 1550 nm, in case of using singlemode fibers, or at 850 nm and 1300 nm in case of using multimode fibers. The target of this work is a testing how the individual parameters of fiber coupler behave whether broad spectrum light source is connected to the input. In sum it was measured four most often used fiber couplers, fiber coupler in port configuration 1x2 with coupling ratio 50/50%, fiber coupler in port configuration 1x2 with coupling ratio 30/70%, fiber coupler in port configuration 1x2 with coupling ratio 10/90% and fiber coupler in port configuration 1×4 with coupling ratio 4×25%. For these fiber couplers it was set insertion losses, coupling ratios, homogeneities and total losses by using a broad spectrum light source. The results are valuable information for companies which deal with optical networks.