Response functions and bandpasses of a miniature fiber optic spectrometer with three read fibers of different core diameters are measured both interferometrically and directly. In interferometrically measured response functions and bandpasses, timedomain and spectral-domain interference oftwo light beams from a laser diode TOLD 9140 operated below the threshold is utilized. It is revealed, in accordance with the theory, that the visibility function for the spatial interference fringes measured in the Michelson interferometer configuration with a broadband detector consists of a Gaussian central peak whose width gives the source spectral width. Similarly, it is revealed, in accordance with the theory, that the visibility functions for the spectral interference fringes measured in the Michelson interferometer configuration by the fiber optic spectrometer are the functions related to the spectrometer response functions whose widths give overall bandpasses. Subtracting the effect of the source spectral width, the spectral bandpasses of the fiber optic spectrometer are determined. In directly measured response functions and bandpasses, the delta-function spectrum of the same laser diode operated far above the threshold is utilized. It is revealed, in accordance with the theoretical assumptions, that the response functions are Gaussian functions. These are compared with the interferometrically measured bandpasses confirming good agreement.

The presented measurement system can be used for environment monitoring in any laboratory or field, hard conditions: for observations the change of the acting forces or pressures as well for observations of the any chemical compositions in air or water in places difficult for human reach. The "heart" of the measurements system is the portable CCD-spectrometer detecting the signals coming from the samples chamber (where is placed the optical force sensor or the medium under inspection). The signals are sending by an optic-fibre bunch from the sensor to the spectrometer. Specialised software allows for collection and visualisation of the spectra and calculation - on line - the value of the force acting on the sensor or changes in a chemical composition in the medium under control.

A fibre optic, fluorescent toxicity test based on a liquid-core waveguide (LCW) is presented here. By employing the LCW it is possible to set up a small and easy to handle system for measurements of weak fluorescence intensity. The use of specific bacteria as "living sensors" and application of the fluorescent measurement technique allows combination of positive features — synergetic reaction to different pollutants and sensitivity to global pollution -ofthe biological monitoring with an objective measure of the technical monitoring. The results of optimisation analysis of the system construction and testing procedure are here discussed. The fmal purpose of this research is to create a new method of water toxicity measurement for in situ experiments.

The single photoelectron counting imaging technique of ultraweak chemiluminescence accompanying oxidative degradation reactions of humus substances under the influence of detrimental environmental physical and chemical factors is described. A new type of a slow scan charge coupled device camera Molecular Light Imager was applied to quantify the spatial distribution of the ultraweak chemiluminescence from natural and model humic acids and mineral soil components (silica gel) exposed to UV-C, UV+VIS radiation, ozone and acid rains. The transformation algorithm was elaborated to obtain the state of the art. pseudocolored images and quantification of the intensity and kinetics and to elucidate mechanisms of the studied processes as well as their environmental significance.

In the report the analytical solution of a problem of tornographic sensing of scattering media (atmosphere, water media) both from the mobile carriers and at the scanning with use of stationary measuring system is proposed, that does not require calculation of. logarithmic derivatives from registered signals. The proposed method does not require the determination of the basic values of the determined optical characteristics (attenuation factors), microphysical characteristics (concentration of gas components), and also on exception of methodical errors caused by instability of parameters of the measuring equipment. The desired characteristics are obtained without differentiation of experimentally measured signals.

The paper presents a branched measurement system allowing automated continuous multi-point measurement of such climate parameters as temperature, relative humidity and atmospheric pressure. The system can operate in difficult conditions including dispersed measurement points and adverse operating environment (broad range of humidity and temperature fluctuation, e.g. cooling industry, meteorological cages, food and pharmaceutical storage facilities, museums, etc.). The paper presents the system's configuration, measurement methods, self-diagnostic and self-testing procedures.

The paper describes the design, development and examination of a prototype dual He-Ne IHe-Xe laser system for gas detection using differential absorption of radiation backscattered from topographic targets. Both lasers were excited by RF discharge. For lengths of 50 cm we obtained the output power of about 10 mW. Using receiver optics with the diameter of 7 cm and thermocooled HgCdTe detector the presence of methane on the distance up to 50m. can be measured. The new solution is under construction. To increase the range of measurement Casseigrain optics with diameter of 30 cm is being prepared. Using the special construction of gas lasers with the output power of 30 mW, the measurement distance of 200 m is expected.

Basic problems existing in monitoring of air and gases are reviewed. The state of the art in related sensor technology is discussed. Especially practical implementation ofnew sensor technology is underlined.

We report the theoretical and experimental study of a temperature sensor based on the changing of the refractive index with the temperature in double core optical fibre. Because of it the coupling coefficient between two cores depends on temperature. This sensor uses the double core fibre directly as a temperature sensor as well to a data transmission. The influence of variations of the temperature from 0°C to 135°C on the coupling coefficient (refractive index) is measured and we received the relation between the temperature and the signal in coupled core. This kind of sensor can be used for public safety, health and security systems.

Results ofpreliminary studies of optical fiber temperature safety system based on thermally induced phase transition in liquid crystal (LC) cell are presented. The system envisaged for harsh environmental conditions has been initially tested in a coal mine.

We present application of continuous and discrete wavelet transform in detection of pulverized coal flame instabilities. Choosing the proper wavelet has been taken into consideration. In this case, possible area of application both continuous and discrete wavelet transform has also been discussed.

The feasibility of the technique utilizing the spectral-domain two-beam interference resolved by a low-resolution miniature fiber optic spectrometer is demonstrated in measuring distances and displacements when two different light sources are used. First, when a low-coherence source, namely a multimode laser diode TOLD 9 140 is used in the configuration of a dispersive Michelson interferometer, a cross-correlation procedure between the measured and the theoretical spectral interferograms is applied to estimate the group optical path differences (OPDs) between beams corresponding to different positions of one of the mirrors of the interferometer and needed in the displacement evaluations. Second, when a white-light source, namely a halogen lamp is used in the configuration of a non-dispersive Michelson interferometer, the measured spectral interferograms are processed by a phase locked loop (PLL) method, which is a special simplified version of the general recurrence non-linear data processing method previously presented, to obtain the corresponding group OPDs between beams in the interferometer or the displacements. The PLL method is realized in iterative mode which provides the unwrapped spectral fringe phase recovery. The accuracy of the iterative PLL method is investigated via processing the measured spectral interferograms.

In non-destructive testing, the magnetic yokes in combination with Hall sensors are frequently used. Such types of sensing circuits are suitable for defect specification with axial geometry lower limit about one hundred micrometers. For inspection of smaller cracks and breaks (less than 10 micrometers) ,the Bi-garnet strip detectors are available. These structures can bring the information related to defect position, but the specification of the defect shape seems to be problematic. One of the possible solutions of this problem can be the using of patterned magnetic thin film structure, which would allow to determine the quality of the inspected body (the number of defects) and in the same time to solve the problem of defect shapes. Such structure can consist of thin magnetic film with in-plane magnetic anisotropy. The anisotropy can be influenced by external magnetic field (for example by stray field from a crack) -the result is the rotation of magnetization in the film plane. This effect can be detected using magneto-optical techniques. When the shape of the crack is in question, the film patterned into 2D grating could respond by the changes of magneto-optical diffraction (polarization properties of the light in various diffraction orders are changed) . The paper is oriented on the experimental study of such structure performed by means of magneto-optical Kerr ellipsometry. Magnetic properties were studied by Kerr (reflection) magneto-optical ellipsometry at 670 nm using differential intensity detection. The measurements were realized in various diffraction orders and the results were compared with the magneto-optical data obtamed from continuous layer. Experimental results and theoretical models support the idea to apply periodical structures with magnetic ordering as sensor unit in diagnostic and measurement processes.

Humidity sensor based on modified PVA structure as active element in leakage detection system in autoclave

Ultraviolet radiation (UV) is used in the textile industry to stimulate fluorescence markers. The textile material is marked using fluorescence markers, which are then visible after exposure to UV radiation. This enables the factory workers to identify the sewing or cutting lines. The interference corrector, reduces the intensity of excess and harmfull UV radiation to chosen level as well as reduce the glare via damping of the textile material' s fluorescence in order to highlight the marks.

The subject of the paper is devoted to noninvasive acquisition of parameters specifying a photoplethysmographic signal (PPG) to which the pulse waveform contributes as the major component. Continuous monitoring ofphotoplethysmograms is of great importance in clinical practice. An optoelectronic sensor based either on reflection or transmission variant of lighttissue interaction can be used to detect the PPG signal, however, there are a lot of difficult measurement problems. Reliability of noninvasive optical sensing depends on specific factors, including physiological as well as technical interferences. In the paper, application of selected manners of digital filtration, which were used to process the raw signals acquired from an optoelectronic sensor placed on the fmgertip, is presented. The transmission variant oflight penetration is considered. The proposed procedures of signal conditioning allow making possible effective acquisition of useful parameters of a raw noisy PPG signal. Measurable quantitative changes caused by qualitative changes in a given pulse waveform shape and disturbances may be evaluated.

The subject of the paper is devoted to optoelectronic acquisition and processing of the pulse waveform of arterial blood, which contributes as the major component to peripheral photoplethysmographic signal. Considered questions concern problems with reliable processing of noninvasively acquired biooptical signals that are influenced by noises, artifacts and other disturbances. The proposed procedures of signal conditioning make possible effective acquisition of useful parameters of a raw noisy PPG signal. Novel design of the adherence circuit that allows eliminating the disturbing low-frequency trend has been presented. Results of verifying studies, where real signals acquired with transmission sensor were processed using this and circuit and classical linear circuit, are discussed.

In the paper a dynamic model of intraocular pressure (lOP) signal has been presented based on results of bibliography analysis referring to anatomy and physiology of eye. Methods of lOP measurement have been presented taking into account their dynamic properties. Study results related to the influence of lop signal averaging time, as well as of tonometric transducer pressure force at the cornea have been presented.

In the paper an application ofthe generalized rn-line spectroscopy to test of biological samples is presented. A generalized rn-line spectroscopy enables an evaluation ofthe parameters (the refractive index, n and the thickness, d) of sub-guiding films deposited on a planar waveguide. Examined layer ofbiological liquid between planar waveguide and prism changes the angular and intensity distribution of rn-line structure of outgoing beam. Some initial measurements reveal an effect of the presence of the films on the coupling angles of the structures. The method is noninvasive and for measurements merely small amount of substance as a drop of tiers or sweat can be used.

This paper presents results concerning the optimization of the measuring system of ImFET model based on the ISFET and ELISA test scheme. In the developed model of the ImFET we obtained linear changes of pH as a function of logarithm of antibodies concentration.

Among various kinds of micro-optical elements, diffractive optical elements are especially attractive because of their functional flexibility in handling wave-front conversion, and because of their planar, compact and lightweight nature what makes them suitable for using in wide range of research, industrial and commercial applications. We present a method of fabricating 8-level DOEs with submicrometer feature sizes in a 3-step lithographic process. In each step a variable-shaped c-beam exposure system is used for writing the pattern that is transferred into substrate by reactive ion etching to form the phase profile. Using this technology several DOEs, including rectangular-apertured micro-Fresnel lens arrays and diffraction gratings were realized on quartz and GaAs wafers. The diffraction efficiencies of these elements were measured to be up to 92%. The lens arrays showed uniform focusing characteristics, and each lens exhibited a good quality of the focused wave front.

This paper presents our works upon production of new pyroelectric material -Triglycine Sulfate (TGS) doped with serine. Many authors investigated influence of various dopants on electric properties of TGS single crystals. In our recent works we investigated influence of organic dopant on domain structure of TGS and correlation of domain structure with the electric properties of new obtained single crystal.

Pyroelectric sensors based on ferroelectric ceramics found wide range of application in the fire protection systems, temperature control units of the energetic turbines etc. It is caused by low production costs and long ageing process in this kind of material. This paper contains the results of investigations upon the ceramics, that found application as active elements of pyroelectric detectors.