The specific properties of the interaction of a high-power ultrashort laser pulse with a solid target related to the processes of target ionization, absorption and reflection of laser radiation as well as generation of ion streams and X- rays are discussed. The results of the experimental investigations concerning the above problems are presented. Some possible applications are discussed briefly as well.

The present paper is devoted to the recent spectroscopic studies of the atomic structure with the use of a Paul trap. Selected results of the experiments performed with the method of the optical-rf double-resonance for europium ion and the preliminary results of preparation towards the study of another rare earth element - praseodymium - are compiled.

Optical methods, which are noninvasive and require small volumes of substance studied, are particularly useful for investigation of local structure and molecular interactions. These methods also proved suitable for investigation of monomers and polymers, which are so common in our civilisation and whose degradation poses an important problem in the aspect of the environment protection. Recognition of the processes taking place in polymers, in particular under the effect of optical irradiation, is a necessary prerequisite for design of materials of exactly predicted properties and able to undergo degradation after use. The paper reports results of investigation of a group of liquid aliphatic diols and their derivatives (unsaturated diesters belonging to dimethacrylanes) carried out using two optical methods the optical Kerr effect and Brillouin scattering. These compounds in the form of polymers have been commonly applied in microelectronics and optical waveguides. Temperature dependencies of these two effects have been studied in the range from 280 to 330K, determining in particular temperature changes of Kerr constants, hypersonic velocities and adiabatic compressibility. The values of the parameters measured were found to depend on the number of elements in the ester group and the temperature dependencies of hypersonic velocity, adiabatic compressibility, and optical Kerr constant were markedly non-linear. The results are presented in the form of tables and diagrams. A discussion of molecular interactions in the liquid esters studied and their relation to the changes in the local structure of the medium is also included.

Influence of the thermal effect on nonlinear optical phenomenon of Kerr effect was studied for two laser beams. This effect is important for subnanosecond or picosecond laser working at a high repetition ratio. Its neglect leads to an even 50% underestimation of the values measured.

Results of temperature dependence of the optical Kerr effect in a series of homologous polyoxyethylenediols are presented. The molecular Kerr constant was found to increase with growing molecular weight of a polydiol. The temperature dependence ofthe optical Kerr effect clearly indicates the influence of viscosity in these media.

Temperature dependencies of the optical Kerr effect have been studied for a series of four analogous diols (of which three contained a heteroatom). The molar Kerr constant was found to increase with temperature below the room temperature and decrease above. The magnitude and character of this change depended on the kind of the heteroatom.

Temperature dependence of the optical Kerr effect was studied in solutions of 1.4, 2.6, and 4.5% n,n- dimethylnitramine in benzene. The optical Kerr constant was observed to decrease with increasing temperature (from 290 to 360K). For solutions of higher concentrations, the temperature dependencies of the OKE signal indicate an increasing role of intermolecular interactions.

The paper gives a general inversion algorithm for lidar's data derivation and profiles of the extinction coefficient, backscattering coefficient and lidar ratio for the lower troposphere. To the best of our knowledge these are the first results obtained with this algorithm.

Laser-produced plasma is an efficient source of x-ray radiation and has been widely used in science and technology. As a result of rapid development of x-ray optics during the last decades a significant increase in x-ray applications has been observed. In the paper we have described conditions of efficient generation of x-ray radiation from laser-produced plasma. These conditions determine characteristics of laser radiation to be used for plasma creation. We have discussed parameters of laser systems used for x-ray generation with respect to applications in lithography and microscopy. We have presented selected laser systems, which have been used for generation of non-coherent and coherent x-ray radiation.

Development of photodymanic method for tumors diagnosis and therapy (PDT) was observed in the early 70's. The third stage of clinical investigations in the USA, Canada, Japan, and in European countries has begun since 1988. Tumors treatment consists in selective oxidation of biological material of a tumor tissue by a singlet oxygen or radical forms. Such forms are generated due to molecular oxygen, soluted in cells, exogeneously introduced photosensitiser which is better accumulated in the diseased tissues than in healthy ones and delivered light of adequate power and wavelength. Such therapeutic method allows selective destruction of tumor tissues, simultaneously protecting the healthy ones. Tumors diagnostics relies on localisation of photosensitisers, absorbed in tumor tissues, by means of fluorometric methods. Investigations with PDT method are carried out in several direction, i.e., synthesis and application of new photosensitisers, design of new light sources, radiation dosimetry in tissues, mechanisms of photochemical reaction, and clinical applications of PDT method. PDT method for tumors treatment compared to traditional ones (surgery, irradiation, chemotherapy) is much more selective but is constrained by many factors limiting its intensive development and clinical applications. In Poland the PDT method is applied in several clinics for treatment of skin tumors, lungs, gynaecological sphere, and urinary bladder. The paper presents current status and perspectives of development of this method. Technology for production of our own photosensitisers (aminoacid complexes and protoporphyrines) is implemented and adequate diagnostic and therapeutic systems have been constructed. Investigations required for specimens admission to clinical application were carried out.

In these paper the selected physical processes of interaction of laser beams with biological tissues are presented. From the wide area of medical applications of laser systems three very interesting problems are presented: medical application of pulsed lasers sources (from some hundred of microseconds to femtoseconds of laser pulse duration), the physical processes accompanied with an interaction of laser beams in spectral range 2000-3000nm, and the selected methods of optical diagnostics of a human tissues parameters. The fundamental scientific, technical, and construction problems of novel laser systems for medical applications are presented. These problems are illustrated by the results of the clinical and laboratory experiments.

The paper presents fibre fluorescence analysers for in vivo examined biological tissues. The systems devoted to clinical investigations are equipped with laser excitation sources; He-Cd (442 nm), Nd:YAG (II and III harmonic: 532 and 355 nm, respectively) and He-Ne (632.8 nm). They allow non-invasive determination of endogenous fluorophones level in any organs as well as monitoring of external sensitisers level when photodynamic method of diagnosis and treatment of tumors is used. Selection of various wavelengths within the range of porphyrines, excitation depends on different light penetration in various tissues. For the tumors localised under mucous membrane, UV, violet, and blue radiation was used for excitation and for deeply localised tumors, a radiation of longer wavelengths (green and red) was used. The carried out clinical examinations showed usefulness of fluorometric systems for diagnostics of skin diseases, gynaecological spheres, and pneumopathies. These analysers can be also applied for environmental protection, food control, and industrial processes monitoring.

The authors present their own experience in restoration of the upper airway using a different source of high power laser. There are many patients with a stricture of the upper airway. One of the most common cause insufficiency of this is nosal polyps. Surgical treatment of polyps till now is not sufficiently effective. For this reason we work out a Nd:YAG laser applying technique that let us to reduce a hospitalization time with elongation of an asymptotic period of our patients. Nd:YAG energy we apply for conchoplasty benefiting of its profound coagulation as a distinctive role. This type of laser is very useful in removing of granulation tissue from different areas of the upper airway. Other applications of Nd:YAG laser in our hands is very useful for: coagulation of vessels in Kisselbach area, especially in Rendou-Osler's diseases, resection of the nosal Septo-turbinate adhesions, treatment of hemangiomas and small papillomas in nasal cavity, diminishing of the hypertrophied mucosa in the nasopharyngeal space as well as, reduction of the uvula and soft palate in OSAS patients. In our department we use a Nd:YAG for treatment of precancerous and early stages of cancer and for a palliation procedures in an advanced cancer infiltration in mouth, pharynx and laryngeal region. For treatment removing of cicatrix tissue in a larynx and trachea we use to use a Holm: YAG laser their very superficial penetration of tissues is used for a coagulation of small vessels too let us to resect it without bleeding from a bony and mucosa tissue, as a fragments maxillary sinus wall, nosal septum crest or spine with resection of the posterior pole of a turbinate. Both laser are conveyed by fiberoptic, to reach a pathological changes in many plans, places for this reason we are able to continuously work on a new its applications.

Small electric signals appear on surface of a cochlea when the ear is stimulated by sound. A level of the signals can be measured of the electric activity of cochlea. The aim of the experiments was recording of changes of the cochlear potentials during argon laser stapedotomy. On the base of the recording the limits of the safe argon laser stapedotomy have been preliminary estimated. The series of argon laser pulses lasting 0.2-0.5 s and of 16 s interval between the pulses are preferable for safety of argon laser stapedotomy. The pulse peak power should be below 1 W.

Laser beam of appropriate wavelength affecting living tissue can stimulate different processes on cell level. If laser beam power is less than about 500 mW no photothermal effects take place in the target tissue. The aim of the experimental studies was to determine whether and how the biostimulation laser beam chan change electrical activity or ear cochlea at guinea pigs. Experiment was performed on 10 pigmented animals. Very different responses of cochlea on laser expose have been recorded. Lack of answer of cochlea on the laser irradiation was observed in 20% of examined cases.

In CDTL PL a set of lasers was installed with irradiation connected to treatment and operation rooms by energetic optical fibers. The introduction of irradiation of particular lasers into fiberguides is controlled by the computer. Fiber couplers were installed on the entrance of transmission fiberguides, and they were connected to optical fibers with different end-pieces according to medical needs.

Electric leep-loop and lasersurgery are modern methods in treatment of diseases of uterine cervix that we can use often exchangeable. Differences first of all relates indications. Lasersurgery we can apply in diseases of uterine cervix channel. Application of electric leep in dysplasia of small grade of uterus cervix channel is possible. Before lasersurgery we should exclude cervical carcinoma, because we don't have histopathological material. Leep-loop conisation we shouldn't apply at young women, who plan pregnancy (risk of cicatristaion and dystokia of uterine cervix.)

Hysteroscopic endometrial resection with the use of electric loop or lasersurgery is the alternative method of treatment of irregular uterine bleedings and endometrial hyperplasia. The effects of endometrial resection with the electric loop and lasersurgery are comparable. The long-term effects of treatment of endometrial lesions with the method of resection are better in case of simple hyperplasia than in atypic ones. The endometrial resection with the use of electric loop or lasersurgery is the safe procedure either for the patient or for medical staff.

Lasersurgery is the very profitable method of treatment of diseases of external sexual organs, with regard to high efficiency and little relapses. Lasersurgery is recommended especially for pregnant women considering possibility of physiological childbirth. We prefer laser CO2 in connexion with colposcope in treatment of diseases of external sexual organs. The application of this method is limited by the high cost of equipment.

This paper describes the microstructure and properties (chemical composition and microhardness) of the surface laser alloyed layer with tantalum as well as coatings, made of Tribaloy T-400 and Stellite 6 powders, deposited by laser cladding. The surface alloyed zones varied in microstructure, zones depth and width, as well as Ta content related to the thickness of the coated layer, bonding paint type and the process parameters (power and scanning velocity). The electron microprobe analysis of melts shows that higher tantalum content in the melted zone resulted from the thicker original Ta coating as well as slower scanning velocity. Scanning electron microscopy examinations show that dendritic structure is typically martensitic when silicon-containing binder was used for powder deposition. Samples covered with Ta and the carbon containing binder showed after laser alloying higher hardness than in case of using silicon-containing binder. Defect free coatings, made of Tribaloy T-400 and Stellite 6 powders, deposited by laser cladding on iron and nickel based substrates are described. The proper selection of the cladding process parameters permitted to get coatings with low dilution of the base material. Cross-sections of such coatings have been examined revealing their microstructure using optical, SEM and TEM electron microscopy, chemical (EDS microanalysis) and phase composition (XRD), hardness and microhardness testing methods. As compared with other deposition techniques the microstructure of the laser coatings showed a high degree of refinement and chemical homogeneity. The grain coarsening was observed in the heat- affected zones and was explained as to be due to the overlapping of subsequent tracks during the coatings deposition. The erosive wear resistance of the coatings has been investigated. In general, the laser deposited coatings turned out to be susceptible for an extensive erosive wear. The effect was explained by lack of feasibility of the coated material to plastic deformation during erosion.

The examinations of the structure, hardness and abrasion resistance of surface layer of Fe-C alloys having the contents of carbon up to 4% and high-speed steel: 6-5-2, 4- 4-2-5+C after laser hardening are presented in the paper. They are compared with the properties obtained after conventional hardening. Laser of impulse operation - YAG:Nd and of continuous operation - CO₂ were used. Analysis of structure was carried out based on metallographic and fractographic examinations as well as on X-ray properties, parameters of laser and conventional heat treatment of steels were defined.

The analysis concerned the influence of laser melting with powder density 0.126x10⁹ W/m² scanning rate 5 m/min on the transfer from liquid to solid state and structure stability in solid state, thermal conductivity, resistance to thermal cyckling of NiCrAlY plasma sprayed coatings on nickel base heat-resistant alloy. It was stated that laser remelting causes structure changes and porosity disappearance, which is the reason for the increase of thermal conductivity of remelted coatings and at the same time decrease of interaction efficiency as thermal barriers and increase of exploatation stability.

This paper deals with creation of the surface layer by means of the laser remelting of thermal sprayed coating. Thermal spraying of Ni, Cr, B and S created the primary coats onto the surface of specimens which base was made of the ordinary carbon steel 45-grade. The coated specimens were remelted with the beam CO₂ 1750W Wagner Basel layer. The hardiness of the remelted layers have highly increased when one compare with it the basic material and, almost twice if one compare it with the hardness of nickel, chromium, boron and silicon.

Cavitation resistance of 45 and 2Cr13 steels with surface layers enriched with Hf, SiC and AlNi was investigated. Each doped element was spread over the sample surface and subsequently melted with core material using CO₂ laser beam. The cavitation tests carried out at the rotating disk facility revealed multiple (5-10 fold) increase of erosion resistance of the processed materials. This effect was not always related to observed changes of microhardness. Moreover, both microstructure of the surface layer and of core material were found to influenced cavitation erosion resistance.

Samples of the 38HMJ steel kept in a liquid nitrogen bath (LN2) at 77 K are treated by a 1 kW CO₂ laser beam of intensity of about 1.3x10₅W/cm² on the sample surface. For thermal processing by means of the 10,6 micrometers radiation the transparency window of LN2 below 0.3 eV is utilised. The irradiation effects are compared with results obtained for the reference samples of the same material under standard gas shielding conditions. Measurements of microhardness HV 0.1 indicated on reduction of the heat affected zone for the LN2 case. A similar effect is observed for higher sample velocities and a value of about 700 HV is obtained in a 30 micrometers surface layer. Surface analysis by means of Auger electron spectroscopy confirms the local nitrogen element of the laser treated areas depending on the processing conditions.

Complex examinations of the structure were performed on thin layers of metallic titanium, titanium nitride and titanium oxide deposited by the means of PLD using Nd:YAG laser. Influence of deposition parameters on the film morphology was under examination. The layers revealed a nano-structure of a good quality. Appearance of a new tetragonal Ti(N)- phase was sated in the deposition of titanium metallic in the reactive chamber with argon atmosphere. The TiN-phase was formed during deposition of titanium nitride, independently of nitrogen flow in the chamber. Transition of oxides from the Ti₂-O via TiO to TiO₂ was observed with increasing flow of oxygen in the chamber for deposition of titanium oxide. TEM examinations of microstructure within the cross-sections of layer revealed a micro-collumnar structure. All of the examined layers were characterised by a strong axial crystallographic preferred orientation which has been stated on the basis of the measured pole figures. The 001 axial texture was identified within the deposited metallic titanium for the Ti(N) tetragonal phase as well as for the TiO oxide, while the 111 texture was observed in the case of TiN nitride. Measurements of the residual stresses of the I-st order in the TiN phase using the X-ray sin²(psi) method, showed the stress level of -5000 to - 7000 Mpa. The residual stresses measured in the substrate of ferritic steel wer about of -150MPa.

The present report describes in an analytic form, the thermal field in a layer of material heated by a CO₂ laser beam moving with a constant speed. The presented description, which is a solution of a power balance of a thermal field includes basic thermal parameters of the heated material varying with temperature as well as variable conditions to absorb the energy of the laser radiation beam by a superficial heat source initiated by the radiation. The heat of structural changes and phase transformations within the area of the initiated thermal field are not considered.

Thin film of hydrogenated amorphous silicon (a-Si:H) were annealed using CO₂ laser radiation ((lambda) equals10,6 micrometers ). The influence of this laser treatment on spectral dependencies of real part of refractive index and absorption coefficient of light in a-Si:H are presented. The values of energy gap have decreased while the Urbach energy increased after CO₂ laser annealing of a-Si:H. The conductivity and photoconductivity of the annealed material have decreased. The power coefficient of the light intensity dependence of photoconductivity has also changed. The influence of CO₂ laser irradiation on the energetic distribution of electron states of a a-Si:H is reported.

An Al-Li-Cu-Mg-Zr alloy was welded in helium atmosphere with CO₂ laser. Full-penetration, single pass butt welds were produced which were generally characterized by low porosity, refined as-cast structure and narrow fusion and heat affected zones. Tensile properties for welded material were lowered in comparison to that measured for unwelded matrix. Initial YS of 487 MPa for unwelded material decreased to 268 Mpa after laser welding as well as the measured elongation decreased from 17.48% to 3.7% respectively. Studies by optical and electron scanning and transmission microcopies were provided in as-welded and as-deformed states to examine the joint's quality and microstructure. Laser produced joints failed in a brittle intergranular manner. The failure mode was connected with the presence of grain boundary precipitates and (delta) -precipitate free zones. The improvement of properties of laser welds was possible by use of appropriate postweld heat treatment.

The analysis of the fluctuations of pressure and plasma radiation observed during welding with a cs CO₂ laser is presented. Welding was done with a continuous wave CO₂ laser. Photon Sources VFA 2500, operating at the power of 1.75-2 kW. The welded materials were mild and stainless steel sheets 0.8-2 mm thick. Shielding gas was argon or helium. Plasma fluctuations were registered in monochromatic radiation with the use of a monochromator and photomultiplier while the pressure variations - with a microphone in the frequency range of 20-2x10⁴ Hz. T he results show that the optical and acoustic signals emitted during the welding process can be used for process monitoring. The most promising method is a frequency analysis based on the Fourier techniques. The Fourier spectra (power spectrum densities - PSD) of pressure waves and plasma emission change with the welding conditions and hence contain information about the process of welding. Power spectra of both signals and their coherence are studied in dependence on the welding conditions. Generally two intrinsic frequency peaks are always present but the relative peak amplitude, exact frequency and width depend on welding conditions. In the case of mild steel 0.8 mm thick when helium is used as the shielding gas these peaks correspond to the frequencies of approximately 1.3 kHz and approximately 3.7 kHz on the PSD of both signals, optical and acoustic. The clear dependence of the measured signals on process parameters shows that they can be used to find the best welding conditions.

At present, in electrical and electronic engineering, conductive materials are applied in the form of thin and thick films. Their properties are different from the properties of those materials in the bulk form, and are dependent on technological processes and substrate properties. Some materials are obtained using laser technologies. This paper presents the results of the research on laser modification of conductivity of surface layers, and the synthesis of conductive films on metallic and non-metallic substrates. Physical and technological conditions as well as a possible range of modification of properties and synthesis of conductive materials with their applications or practical prognosis.

Attempts at increasing the reliability of assembly of power transistors the authors have proposed a new method for thick wire bonding. Bonding produced in this technology has the form of weld made by the pulsed laser beam. The results of some investigations into the proposed method are presented. The results of studies on semiconductor test structures bring the hope for the positive solution to the problem of increasing the reliability of assembly of such structures.

In the paper a laser method for producing micro-areas of a high resistivity has been presented. To obtain such areas, a local character of the pulsed radiation beam interaction was used, which - in the laser alloying process - allowed the generation of an alloy in a limited spatial area (of a volume of 0.01 - 1 mm³). In the case of thin wire and foils the alloyed micro-areas comprise the whole section of the element subjected to treatment. For some cases, the required energetic parameters of the beam have been established. The conditions for obtaining the homogeneity of an alloyed area for different lasers (pulse or cw) have been determined. The results of investigations into electrical properties of the elements have been presented. The use of such areas for fuse-links has been suggested. Using the microscopic infrared thermography method, the heating of the elements containing resistive areas with the flow of current of a fixed value and with jump changes in current intensity has been determined.

The paper presents, the first in Poland, application of a Q- switched Nd:YAG laser for cleaning the surfaces of the Tomb of the Unknown Soldier situated in Warsaw. There are also discussed an influence of laser beam parameters on the rate and width of the removed layers, being the hardened black layers, that were formed on the Tomb during the last ten years.

Four different full-field interferometric systems using variable laser wavelength are presented. The measurements of inplane displacements and strains on the surfaces of objects under load with the aid of the grating interferometer and digital speckle pattern interferometer are described. The latter system allows the determination of the amplitude and phase distributions of the modes of vibrating surfaces as well. The measurement of in-plane displacements of rough surfaces using scattered light beams and the determination of surface shape by heterodyne interferometry are presented. In the first three cases current modulated laser diodes currently modulated are exploited, in the last one - wavelength changes of laser radiation by acousto-optic modulators are introduced.

Quasi-monomode optical fiber sensors, used an input of systems for external force detection and classification, are widely described in references. Feature extractors in such systems are often based on computer generated holograms (CGH) and classifiers are usually built as artificial neural networks (ANN). The use of CGH instead of ring-wedge detector gives possibility of easy change of ring and wedge sizes. In this paper we present our method of CGH optimization. This method is based on evolutionary algorithms and elements algorithms and elements from rough set theory (RST). The results of classification of features obtained by applying optimized by our method CGH confirm that proposed approach can be successfully used for detection and classification of external force. All what is needed for this purpose is to pass coherent light through quasi-monomode optical fiber, and to place CGH in a focal plane of the lens. As CGH regions are the subject to be optimized to given application and therefore minimized in size, the resulting hybrid optic-digital system can be compact and relatively cheap. The experimental results for classification of generated by optimized CGH features confirmed the good overall quality of the proposed system.

The structures under study are thin polymer layers deposited on planar waveguides. Such coatings are generally used within waveguide sensors. Because of the low refractive index and sub-waveguide thickness they cannot guide the light, but they influence the modal propagation of light when deposited on the planar waveguide. Measurement of the coupling angles to these structures for different wavelengths yields values of the effective indices to the two dispersion equations with two unknowns and results in evaluation of parameters of the structure.

A KrF excimer laser (248 nm) was used to induce DC corona discharge streamers in air between the electrodes of a needle-to-plane geometry. The UV laser beam pulses were transformed into the form of a laser sheet (1.5 mm thick and 20 mm-wide) that was positioned along the axis directed from the needle electrode to the plane electrode. The laser pulses were time-synchronized with the exposure of an ICCD camera that record images of the corona streamers induced by the laser sheet. The laser pulse energy flux (75 MW/cm²) crossing the gap was high enough to induce corona streamers with a reliability of 100% even at relatively low operating voltages (e.g., 15 kV) at which self-sustained streamers could not occur. Due to the full synchronization of the corona streamer onset, induced by the laser pulse and the exposure of the ICCD camera, 2-D visualization of the corona streamer evolution with a time resolution of 10 ns was possible. The recorded images made possible determining such features of the corona discharge streamer as its velocity (2.5 10⁵ m/s) and the diameters of the leader channel (200 micrometers ) and the leader streamers (100 micrometers ).

Pulsed metal vapour lasers in general, and pulsed copper vapour lasers in particular are now considered to be enabling technology for a number of important processes. The pulsed conventional copper vapour lasers (CVLs), the technology of which has continued to develop to the point today where multiple green/yellow laser beams of more than 1 kilowatt average power are routinely generated at around 1% efficiency (Lawrence Livermore National Laboratory), are the highest power visible lasers ever developed. Today the conventional CVLs producing 100 W average power at 5 kHz pulse recurrence frequency and about 1% efficiency are at the laser market. However, due to their high operating temperatures (1500-1600 degree(s)C), the conventional CVLs are of complex construction, require flowing gas system, and have long warm-up time (90-120 minutes). The pulsed copper bromide (CuBr) laser is another representative of the copper laser family, which does not exhibit the disadvantages associated with the conventional devices. CuBr lasers have been demonstrated to have high-efficiency (2-3%) and high specific output powers (0.1-1 Wcm^-3). Up to now a CuBr laser of 120 W average output power has been reported. There is no other type of laser which can deliver such a high average power in the visible range with such a high efficiency and high beam quality. The rapid development of laser technique in the past decade allows to introduce new methods of measurements into various areas of scientific and technical activities. One of the possibility is to apply the laser technique to visualisation of flows and to particle image velocimetry (PIV). In this paper we present the potential of CuBr laser in this field.

It is shown that far field patterns of argon laser beam interacting with dyed foil of polyvinyl alcohol (PVA) provide information on the mechanism of local foil discoloration or at least on a few properties of this process. In particular far field patterns observations allow discernment if the process is reversible (or a superposition of reversible and irreversible processes), photothermal, photochemical or produce a stretching in sample (photoizomerisation). The effect was studied in PVA foil containing methyl red, photosynthetic bacteria, their fragments and pigments. Apart from indicating the possibility of using the far field patterns for discernment of the foil discoloration mechanisms, the results reported point to the perspectives of using the foil for laser beam modification, shift or modulation, as well as elements of optical memory.

The growth of aerosol and ozone concentrations in the troposphere stimulates development of monitoring techniques allowing their detection. DIAL (Differential Absorption Lidar) is one of the most promising methods. It allows the remote measurements of selected pollutants within the range of few kilometers and with spatial resolution of few meters. We introduce the basic principles of the DIAL method and describe shortly our mobile lidar system. We present and comment selected registrations of ozone and aerosol concentration distributions obtained during summer field campaigns of 1997 and 1998.

Computer simulation of multispectral detection of laser radiation is presented. The theoretical analysis concerns the device which applies the special uncooled MPC detectors. The theoretical results are confirmed by measurements in real conditions.

Theoretical design and practical performance of uncooled MPC detectors are presented. Based on the detectors performances the possibility of detector's application in laser radiation multispectral detection is showed.

Computer simulation of uncooled Hg_1-1Cd_xTe detectors is presented. Based on the obtained characteristics the possibility of detector application in laser radiation multispectral detection of laser radiation is estimated.