This paper presents recent developments in investigations of glass integrated optical circuit. Components are realized by the waveguide technologies: single ion exchange, creating of buried strip waveguides, double ion exchange, doped glass strip waveguides. Equipment and elements on glass planar waveguides and multimode interference structures in the technology of elements of integrated optics.

Optical materials prepared by the sol-gel process are of current technological interest. Sol-gel silica glasses doped with rareearth (RE3+) ions are an important class of optical materials with applications including solid-state lasers, optical waveguides, fiber amplifiers and devices for optical communications. In this paper, we describe the preparation of rareearth- doped silica-gel glasses and discuss the infrared properties of silica structure as a function of heat treatment. The samples were prepared from tetraethoxysilane (TEOS), water, ethanol, fumed silica and soluble in a water or ethanol the salts ofthe RE3+(Er3+,Nd3+,Sm3+,Pr3+,Eu3+) elements.

The work discusses the application potentials of sol-gel technique in the technology of planar waveguide sensors. The capability to form refractive profiles with the use of various techniques applied in planar optics have been compared. The authors present the results of investigation studies involving the application of sol-gel technique of the oxide system Si02:Ti02 for the formation of sensor layers, mask layers and waveguide layers. The influence of the thickness of waveguide layer and of its refractive index on the sensitivity of the meter measuring the refractive index changes and working in the difference interferometer system has been investigated.

Applying the sol-gel method, there were obtained gel glasses from the oxide systems SiO2—TiO2 and SiO2—Bi2O3, which were next subjected to leaching in HCI to obtain the gradient of the refractive index. As the final material there were obtained gradient glasses with the refraction gradient from 0.01 to 0.06. The developed method of producing the glasses may be applied to obtain gradient arrangement of fibres used in optics and optoelectronics.

The search for new materials of possible application in optoelectromcs and optical fiber technics includes a wide range of amorphous glassy materials. In this work we investigate lead-bismuth-gallium oxide glasses. These materials are characterized by good transmittance in a far infrared spectral region as compared to other oxide glasses and also interesting properties in nonlinear optics. Those features together with a conventional production technology allow to consider them as possible materials for optoelectronic devices and glass fibers transmitting in an infrared region.

The paper present the first stage of researches aiming to elaboration of Er3+ and Cr3+ ions doped ytterbium-phosphate laseroriented glasses pumped with flash lamp or with laser diode (?=97Onm) and emitting "eye-safe" radiation (?=1.54?m) and active fiber-oriented one for amplifiers on wave 1.53÷1.55?m. Worked out glasses are characterized by low coefficient of thermal expansion (high resistance on thermal shock), do not crystallize or show slight inclination to devitrification in temperatures of fiber forming and possess advantageous rheological characterization. Spectral and spectroscope investigations of glasses show on their usefulness for laser applications. Especially refers this to glasses with simultaneous content Er3+ and Cr3+ ions giving strong luminescence.

This paper presents method of calculations of absorption loss of single mode optical fibers bringing by groups OH. It is examined an interaction of distribution of electromagnetic field and profile of diffusion of water. Presented method is used in elaboration of theoretical base of hybrid methods of optical fiber production in Laboratory of Optical Fibers Technology UMCS.

This work contains results of experimental work on elaboration of hybrid method of telecommunication optical fibre production. Two series of single-mode fibres with different cut-off wavelengths were produced by means of MCVD method. Their spectral attenuation was measured and loss carried in by OH groups was determined. When the fibre was produced, times and temperatures of diffusion of water towards the core of fibre were measured. On this basis calculation of mutual interaction of diffusion profiles and distributions of fields was done. Results of calculation and measurement of loss carried in by OH groups were compared.

New epoxyacrylic oligomers were received and used as the main components of the compositions that get hardened under Uv radiation. In order to synthesize the epoxyacrylates the diglycidyl ethers were used which contain a changeable number of carbon atoms in the cyclic aliphatic ring between the aromatic rings. The lacquer composition contains also an active diluent and a photoinitiator. As the active diluents the butyl acrylate was used, then 2-ethyihexyl acrylate, styrene and 2,2'- dimetoxy-2-phenylacetophenone as the photoinitiator. The physicochemical and mechanical properties of the received compositions were determined both before their hardening and after it. A high mechanical resistance ofthe foils received as result of polymerization of the studied compositions was confirmed. It makes them to be a preferable material for the hard protective coats of optical fibers.

A method of preparation of urethane-acrylic oligomers was elaborated. They were applied as the main components of a composition, which harden within a short time under the influence of irradiation with UV light. The following substances were used to the synthesis: tolylene, isophorone and hexylene diisocyanates, oligo(oxypropylene)diol, triethylene and dipropylene glycols, hydroxyethyl and hydroxypropyl methacrylates as well as some alkylene acrylates and methacrylates as active diluents. The physicochemical and mechanical properties ofthe received compositions were determined before the hardening process and soon after it. It was found out that the polyurethane-acrylates are characterised by a considerable mechanical durability and a high adhesion against various materials, which makes them to be preferably used as the protective coats for the optical fibres.

The goal of this work was to construct an optical fibre with a thick core made from multicomponent glass and a thin cladding made from quartz glass. The method to calculate durability of such an optical fibre has been worked out. The fibres with cores from commercially accessible multicomponent technical glasses have been prepared. Partial agreement of quantitative theoretical description with the experimental data has been obtained. Durable structures of optical fibres with numerical aperture of 0.35 have been produced from pyrex glass (core) and quartz glass (cladding).

This paper presents analysis of light propagation in liquid crystal (LC) optical fiber waveguides with elliptical cores. In theory, the modal structure and its characteristics of the waveguides composed of extremely low-birefringence nematic liquid crystal acting as an elliptical fiber core and characterized by an index ellipsoid has been analyzed. The liquid crystalcore fiber waveguides have been modulated and simulated by using the Beam Propagation Method (BPM). Selected configurations of the nematic liquid crystal confined in the fiber core and their influence on modal structure of the anisotropic cylindrical waveguides have been analyzed. The theoretical analysis was accompanied by experiments with elliptical-core LC fibers in the polarimetric configuration. The results obtained indicate homogeneous LC orientation inside the elliptical core and as a consequence, in a certain temperature range, the LC waveguide acts as a fiber polarizer.

The new approach to multifanctional sensor of physical values designing on the base of fibre lightguides (FL) with a control birefringence and liquid crystal material is proposed. The fiber principle of operation is based on light beam, which passes through the lightguide, weakening under the external influence. As an informative parameter the light amplitude, phase, frequency or polarization can be used. The sensors can be divided by their functional purpose in FL circuit: as a sensitive element or as an optical channel, that connects the separate elements. The cell with liquid crystal active medium contains a FL in cell bulk. In presence of external influences (temperature, pressure, electric and magnetic fields etc.) the liquid crystal molecule orientation leads to change optical characteristics of the active material. This process is determined by light flow parameters in FL. Such a sensor construction gives the FL and liquid crystal element with a thickness of 25 mm. The induced cholesterics on the base of cyanobifenil mixtures and high effective non-liquid crystals dopant BIXH for control of physical parameters are investigated. The sensor allows to measure the electric fields — about 106V/m, magnetic fields - up to 1 T and temperature ranging from 243K to 333K.

It is proposed to use in light guide medical devices (LGMD) with selective reflected optical part the spectra correction and controlling of radiation power with spectra characteristics in the limits of bioactive effect. We offer to use compact short arc discharge metal-iodine low power radiated sources (RS) in different electrical modes. The experimental outcomes for such 200 VA RS in LGMD show, that such RS allows to obtain determine corrected spectral bands and radiated power control with minimal spectral shift into long wavelength range.

A new concept of optical fiber sensor for automatic recognition and classification static images has been presented. The sensor based on a fiberscope connected with appropriate detector, which works also as classifier. The main role of the fiberscope is transmission and magnification of analysed image. Presented system is tested for automatic estimation engine condition based on exploration of metallic fraction gathered from lubricating oil.

Photonic vibrometer is used for non-contact vibration measurement. Information about changes in distance between the vibrating target and the fiber bundle tip is expressed as a change in the intensity of back scattered light by the target. The optical extender accessory offers the advantage of considerably increased operating distance (from about 1mm to 40mm).

In the article we present application of wavelet adaptive filtering of output signal of fibre-optic flame monitoring system. It enables better distinction of output signals correspond to various types of fuels (mazout, coal) and improves detection of flame instabilities.

Three types of periodical structures formed on fibre cladding are observed. First one formed on the fibre cladding, which resulted in refractive index changes along fibre axis, second one formed as corrugated boundary between fibre core and cladding, and third one created on the fibre cladding as corrugated periodical grating. Sensitivity and characteristics of such structures are shown. Finally, achieved results are considered and analysed.

In the paper, a quasi-distributed fiber optic temperature sensor working in transmission mode is presented. This sensor is based on partial reflection from silicone resin layers placed between ends of adjoining optical fiber segments. For signal detection. an optical time domain reflectometer was used. The transmission mode of operation allows temperature to be measured in up to tens points whose spacing along the fiber can range from few centimeters to few kilometers. A complex calibration procedure of the sensor is also presented.

In the paper testing and investigation of temperature luminescent fiber optic sensors were presented. The main characteristic domain of fiber optic sensors are the non sensitivity to strong electromagnetic disturbance radiation, the complete galvanic insulation as well as the full safety their using in places endangered of explosions and a risk of fire. For this reason fiber optic sensors may chance to be the interesting and valuable completion of electric and electronic sensors for industrial and scientific application. There are group of luminescent materials, which after their excitation, emit the own light and the properties of emittedlight depend on temperature. On temperature depends spectrum of light, its intensity and dynamic parameters of light decaying after excitation. These effects have found application in sensor techniques. We have elaborated fiber optictemperature sensors based just on dependence of decaying time on temperature. These sensors are planed to applied in high power transformers and power machines for their work state control.

The paper describes an evanescent wave sensor model operating far from the modal steady state. Assuming that of the numerical aperture varies exponentially with the fibre length and the light losses are proportional to the local and fibre numerical apertures ratio, the sensor description was evaluated. Experiments, in which the sensor absorbance versus the refractive index of the medium surrounding the fibre core and the fibre sensing section length, were made to confirm the theoretical model of the sensor and good agreement was observed.

In the article the preliminary solution and a concept of industrial version of the fibreoptic system for monitoring of fuel-oil burners in power boilers is described. It eliminates disadvantages of currently used systems and extends its diagnostic capabilities. Measurements made using the prototype monitoring system are also presented.

In the work we describe the process of design of fibre-optic probe for the flame monitoring system by method of finite elements. Probe made according to the design has successfully passed tests made in industrial boiler 0P650.

An interferometric optical fiber sensor intended for use in Weigh-in-Motion systems is presented. The sensor uses a modified Michelson interferometer configuration with two sensing arms. To avoid polarization induced fading the force acting on the sensor is measured indirectly, using modulators which convert it to pressure. Operation of such modulators was verified by experiment and based on its results a laboratory model of a sensor was built and tested.

The results of our research of the multichannel simulated transmission for the erbium doped fibre amplifier (EDFA) is presented in the work. The basic parameters of amplifier were measured by using the optical spectral analyser ANDO AQ631 . A multimode diode laser operating below threshold current was used as a source of the signal in the main line. Longitudinal modes of various wavelengths were treated as single transmission channels.

In this paper, some results of optimization of process of arc fusion splicing of single mode optical telecommunication fibers in climatic circumstances characterized by temperature changes in the range t =-2 °C ÷ 32 °C and by relative humidity variations in the range RH = 30 ÷ 92 % are presented. The means of determining jointly the climatic circumstances: temperature, relative humidity and dew-point excluding possibility of performing a paper arc fusion splicing of optical fibers is reported. The results of measurements of attenuation, reflectivity and mechanical strength of arc fusion splicing of single mode telecommunication optical fibers produced in extreme climatic circumstances are presented as well.

In this paper, the influence of diffusion processes of Ge02 impurity during arc fusion splicing on the parameters of splices of single mode telecommunication fibers of different types are discussed. The calculated values of diffusion coefficients of Ge02 in Si02 for fusion temperature are given. Moreover, assuming different diffusion models, the parameters of the dopant diffusion area, from the core to the claddings of fused fibers, are calculated. On this basis, the optimal values for fusion times and currents for optical telecommunication fibers of different types, to fulfil the telecommunication requirements on splices regarding their loss, reflectance and resistance to tearing, are calculated as well. The results of measurements of loss and mechanical strength of splices for the automatic and optimized programs for spliced connections of the TrueWave® optical fiber with other single mode telecommunication fibers are presented.

Using the method of m-line spectroscopy [1] it is possible to determine parameters (thickness and refractive index) of thin films deposited on planar waveguides through indirect measurement of changes of coupling angle to the waveguide. The subject of the study were thin organic films deposited on waveguides by casting diluted polymerizable solutions, and by spin-coating thin polyimide films. These films are developed as active coatings in waveguide sensors. Numerical calculations (applied for three-layer structures) after modification to a four-layer structure allows for determining the parameters ofthin films.

Nowadays, there are many universal laser diode supplies with very good parameters. These prices are considerable. Their employing in end application and students' laboratory is the question for discus [1]. Authors worked out low cost, simple in construction from easy to obtain parts laser diode supply. To aim this task the SPICE model oflaser diode with detector was elaborated.

The single-mode fibre erbium doped optical amplifiers are well known. They have high gain in wide band. They works in telecommunication purposes mainly [1] but the idea of optical signal amplifying is interesting also in other areas. One of intriguing application is free space signal pre-amplification for example in distance meters. In such implementation the multi-mode active fibre usage should be considered. There are a few literature positions that focus on this area [2]. Therefore, the multi-mode fibre amplifiers analysis was performed by authors. This paper presents a theoretical basis of multi-mode fibre amplifiers based on energetic and propagation equations. The investigation of amplifiers pumped codirectionally and contradirectionally introduced for fibres Er and Nd doped was taken.

A simple modification ofthe typical wide-band monochromator based cut-back system for fiber transmission measurements is presented. To increase the spectral resolution for fiber Bragg gratings measurements the properly blazed monochromator grating was inserted, stepping motor resolution increased and mechanical chopper thoroughly redesigned to avoid signal phase fluctuations. As the result spectral resolution of 0.16nm and signal dynamic range of 30dB was achieved in the 1.5µm region.

The paper presents the structure of two laboratory models of waveguide planar sensors of refractive index changes of liquids. Both systems have been designed basing on plasmon resonance along the interface between metallic layer and measured liquid. The models have been constructed basing on planar waveguides as well as on strip waveguides. The measurement results of spectral transmittance of the investigated structures have been presented as the function of refractive index ofthe measured liquid.

A measuring assembly to examine the distribution of light intensity in near field of planar and strip waveguides was presented. The image of near-field intensity distribution of waveguide modes was showed as well as their interferrential changes caused by the change in optic features of waveguide structure. The presented version of the station was the one to measure the power guided in particular modes with the same polarisation states.

We demonstrate the idea of specific launching of laser radiation into a birefringent fiber using He-Ne Zeeman laser with two orthogonal modes operating on two different frequencies with their stable offset. Heterodyne detection of propagating modes allows analyzing phase shifts and coupling effects in fibers.

The study of guided modes in planar thin film structures allows a precise characterization of the refractive index, the thickness, and the optical anisotropy. On the base of matrix elements the reflection coefficients between isotropic and bi-gyrotropic substrate are analyzed. The permeability tensor effect on waveguiding at transversal magnetization in a monolayer system is described. The experimental possibilities of dark mode spectroscopy (DMS) in the analysis of the planar magneto-optical systems inclusive of the permeability tensor element specification are discussed.

In the paper we have determined the dependence of the difference of propagation constants of orthogonal modes of the same order on the refractive index ofthe cover, for planar waveguides obtained during the ion exchange K+-Na+ in the glass BK-7. Similar measurements have been made for the exchange Ag+-Na+, determining also for that case the influence of heating time on those parameters.

The results of fiber-optic polarizer preparing in base of a fused biconical taper technology are presented. A new element of this work is use of a high-birefringence fiber with D-type cladding. The received results have been compared with theoretical investigation obtained for suitable prepared substitute model of polarizer structure. All results ware made for elements working on visible range oflight (He-Ne laser).

Forming of solitons in nonlinear lossless lightguide, when initial pulse is a chirped square pulse, is discussed. The Nonlinear Schrodinger Equation for complex initial conditions is solved numerically by Split-Step Fourier Method and Beam Propagation Method. Differences between results obtained with the use ofboth methods are estimated.

The paper provides the discussion on the application of matrix method for the analysis of planar waveguide structures. The method has been based on the 4x4-matrix technigue. In the paper, we present the method applied for asymmetrical planar waveguide structures of step-index type and for gradient-index waveguides. The equation characteristic for structures ofthat type has been presented as well as expressions for effective refractive indexes of substrate and cover. The paper presents the analysis results of selected structures of planar waveguide sensors obtained with the application of the matrix method.

The propagation characteristics of the structure consisting of two asymmetrical optical rib waveguides, which are fabricated on a common substrate, are investigated. The dependence of the coupling length and the number of the guided supermodes on the structure dimensions, wavelength and polarisation are studied. The application of the analysed structure as an optical directional coupler is discussed. The analysis is carried out using the Semivectorial Finite Difference Method while the eigenvalue problem is solved using iterative methods.