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This paper presents a brief review of the developed laser technologies and lidars with hyperspectral resolution and extremely high sensitivity for the diagnosis of complex impurities in the atmosphere and hydrosphere via Raman spectra. The technological foundations of the research, exploratory, and ecological studies of hydrocarbons are developed using Raman lidars. The prospects of hybridization of Raman spectrometry and video spectrometry in remote probing are considered.

We present the results of theoretical and experimental studies demonstrating the possibility of developing an oxygen-iodine laser (OIL) with direct optical pumping of molecular oxygen involving inter-molecular interaction with charge transfer from donor molecule (buffer gas) to acceptor molecule (oxygen). This interaction lifts degeneracy of the lower energy states of molecular oxygen and increases its absorption cross section in the visible spectral region and the UV Herzberg band, where high quantum yield of singlet oxygen is achieved (QY ∼ 1 and QY ∼ 2, respectively) at the same time. A pulse-periodic optical pump sources with pulse energy of ∼50 kJ, pulse duration of ∼25 μs, and repetition rate of ∼10 Hz, which are synchronized with the mechanism of singlet oxygen generation, are developed. This allows implementation of a pulse-periodic oxygen-iodine laser with an efficiency of ∼25%, optical efficiency of ∼40%, and parameter L/T ∼ 1/1.5, where T is the thermal energy released in the laser active medium upon generation of energy L. It is demonstrated that, under direct solar pumping of molecular oxygen, the efficiency parameter of the OIL can reach L/T ∼ 1/0.8 in a wide range of scaling factors.

Detailed description of stages of computer processing of the shadowgrams during implementation of a modern quantitative Foucault knife-edge method is presented. The map of wave-front aberrations introduced by errors of an optical surface or a system, along with the results of calculation of the set of required characteristics of image quality, are shown.

We introduce a concept of underwater lidar based on compact Yb-doped high energy femtosecond fiber laser. It is assumed that simultaneous registration of scattered supercontinuum radiation, conical emission and fluorescence from filament in water may allow obtaining information about media pollution as well as about oil and gas presence.

The experimental results presented in this study focused on the study of biological processes caused by exposure to the coating layers of the laser green light seed (λ = 532 nm) range for the larch, violet (λ = 405 nm) and red (λ = 640 nm) for spruce. Spend a series of experiments to study the dependence of crop seed quality (spruce and larch from the pine family) from exposure to laser radiation under different conditions. In all the analyzed groups studied seed germination and growth of seedlings exposed to laser exposure, compared with the control group. The results showed that the higher percentage of germination than seeds of the control group.

Experimental results presented in this study tends to explore viruses in the water for their further decontamination under the influence of laser radiation (λ=220-390 nm). Conducted a series of experiments to study the dependence of water quality from the effects of laser radiation. Correlation between degree of survival of viruses and power density. The results showed that all the analyzed samples of water is clearing from bacteria to 98%. Preliminary tests of the prototype laboratory system UFOVI has opened up new opportunities for water sterilizing.

The experimental results presented in this study are the early studies of germination on the example of Picea abies and were aimed at testing the germination of seeds and the development of morphology, caused a therapeutic effect on the laser radiation field in the early stages of development under the action of ultraviolet and red light in the spectral range of 405 nm and 640 nm. A set of seeds irradiated at various energy doses within the same time. The experimental results analyzed in parallel with control group. In all analyzed seeds were studied the germination and growth of seedlings. The results showed that the percentage of germination higher than control group Samanids all of the recurrence options.

The behavior of two lines P1-0(11) and P2-1(8) weakly absorbed by the atmosphere is experimentally investigated in the spectra of cw chemical multikilowatt HF lasers of five types that differ in size and construction scheme of the nozzle array. It is shown that the intensity of these lines can be controlled within certain limits by varying the gas-dynamic regime of the laser operation, the chemical composition of the active medium, the orientation of the optical axis of the cavity and the cavity feedback factor, and the construction of the nozzle array.

An optical attachment of an excimer laser beam that enables the transformation and optimization of spatial characteristics of a coherent UV beam was studied in an experimental setting. Experiments revealed that a rectangular 3 × 20 mm laser beam with the a divergence of 2 × 5 mrad attains a square shape of 20 × 20 mm and a divergence of 5 × 5 mrad in orthogonal directions after passing through the beam attachment. It is demonstrated that the application of a beam attachment in installations for material microprocessing simplifies optical layout of the illumination module allows one to obtain optimal homogeneity of sample illumination (under 2%) upon the projection of the image on the processing plane of the sample with submicron precision and to reduce the radiation load on optical elements via the elimination of hot spots.

One of the highly effective methods of operative remote environmental monitoring on land and water surfaces is laser sensing. It knew that the Raman scattering cross section is very small (10 -25 -10 -27 ), so in some cases radiation back into captivity to the target could be a few tens of photons. For high-speed sensing, speed of processing and ease of use lidar units required for the use of appropriate hardware and software systems used for the decision of tasks of collecting, processing, storing, organizing large amounts of data.

There are already significant amounts of hazardous radioactive substances in the world. It, potentially, leads to a major damage and contamination of large areas. Laser sensing can serve as a highly effective method of searching and monitoring of radioactive contamination. We developed a laser system to detect accidental leakage of radioactive materials. Methods of fluorescence spectroscopy and Raman spectroscopy allow to detect a concentration of uranyl U235O2 and U238O2 at 500 ppb, and Sr90 and Cs137 at the level of 1 ppm at 100 m distance from the object.

We have demonstrated airborne lidar possessing spectral resolution λ/Δλ ≥ 1000. Its ultraspectral resolution is provided by the dual polychromator based on large-sized stigmatic holographic gratings. The lidar was tested in a real-life flight conditions at the transcontinental gas pipeline. It has performed aero search of leaks and measurements of the leaked gas concentration.

The results of experimental and theoretical modeling of multistage Raman conversion in compressed hydrogen with a buffer gas under using the lasing of neodymium-crystalline mediums to obtain the seed radiation for CO 2 power amplifier in the double-pulse and bispectral primary laser while maintaining efficiency of LPP EUV source are presented. This scheme allows as significantly decrease level of pumping consumption and tune a delay time up to 820 ns between a weak power (initiating a plasma cloud) and main power pulses irradiated the converter target. The lasing intensity in the focal spots was 0.2 GW/cm 2 and 5TW/cm 2 respectively for wavelengths of 1.064 μm and 9.2 μm.

Optical limiting properties of C60 and C70-doped organic thin films (polyimide, 2-cyclooctylamino-5-nitropyridine) under a laser irradiation at wavelengths of 532, 1047, and 1315 nm have been studied. The films can be applied as laser power attenuators at a laser energy density of more than 2 J·cm−2 and at a laser energy density up to 0.8–1 J·cm−2 in the visible and near infrared spectral ranges, respectively. Reverse saturable absorption and the complex formation have been discussed to explain optical limiting results. The place of the materials studied can be predicted among other nonlinear optical systems attenuating high energy density in the near infrared.

The spectral distribution of laser radiation power generated in two (initial and final) regions of the flow of an active medium formed by a three-jet nozzle array of a supersonic cw chemical HF laser embodying the nozzle-nozzle-nozzle mixing scheme is investigated experimentally. It is demonstrated that the spectral lines can be selected by merely varying laser operating parameters, such as the feedback factor of the cavity, the orientation of the optical axis of the cavity with respect to the exit plane of the nozzle array, and the degree of secondary dilution of the active medium with helium. This method results in the selection of one line P1−0 (6) with a power as high as 80% of the total radiation power and two lines P1−0 (5) and P1−0 (6) with a power of 100%.

We experimentally studied the spectral parameters of the radiation generated by supersonic continuous-wave DF lasers with nozzle blocks of two different configurations (nozzle-nozzle and nozzle-radial-expansion-injector mixing schemes). We demonstrate the effects of the excess secondary-fuel (deuterium) ratio, the orientation of the optical cavity axis relative to the nozzle section, and gas-dynamical reactant mixing conditions on the spectral composition of the radiation. We show that the DF-laser spectrum can be controlled to a certain extent by varying these parameters.

This paper describes a laser system that provides dual-pulse bispectral excitation of a laser plasma in an extreme-UV source for nanolithography in this spectral region. The radiation converter is based on a low-power YAG:Nd laser and a powerful CO2 laser. A saturating signal is injected into the power stage of a CO2 amplifier by subnanosecond pulses at wavelength 9.2 μm from a stimulated-Raman-scattering amplifier pumped by the radiation of an optical parametric oscillator that uses the radiation of a YAG:Nd solid-state laser (the master oscillator). Mechanisms for high-efficiency conversion of laser radiation into the extreme-UV region (13.4 or 6.7 nm) were theoretically and experimentally studied. The laser system makes it possible to independently establish the optimum delay time between the pulses in order to increase the output of the extreme-UV radiation.

Remote laser spectroscopy availability for airborne search of radionuclides polution has been examined. Experiments were carried out under the CARS circuit. The method of remote detection a radionuclide in atmosphere from container burial places and in places of recycling the fuel waste of the atomic power station is elaborated. Preliminary results of investigation show the real possibility to register of leakage of a radionuclide with concentration at level of 1012÷1013 см-3 on a safe distance from the infected object.

We developed a Raman lidar with ultraspectral resolution for automatic airborne monitoring of pipeline leaks and for oil and gas exploration. Test flights indicate that a sensitivity of 6 ppm for methane and 2 ppm for hydrogen sulfide has been reached for leakage detection. The lidar is based on the CARS method with a Ti:Sapphire pump laser and a frequencydoubled YLF:Nd probe beam whose frequency is displaced by a BBO crystal. In ground-based experiments, a detection level of 3 to 10 molecules has been reached.

Laser sensing can serve as a highly effective method of searching and monitoring of radioactive contamination. The first method is essence consists in definition the Sr90 and Сs137 concentration by excitation and registration of fluorescence at wavelength of λ = 0.347÷7.0 μm at laser sounding. The second method experiments were carried out under the Raman-scattering circuit. Preliminary results of investigation show the real possibility to register of leakage of a radionuclide with concentration at level of 108÷109 сm-3 on a safe distance from the infected object.

An optical limiting (OL) effect of the laser radiation over IR range in organic compounds based on polyimide has been studied. The non-linear transmission at a wavelength of 1315 nm as well as spectral properties of the compounds have been investigated. The results obtained have been explained by the donor–acceptor interaction mechanism that affects non-linear-optical properties of organic molecules. The fullerene-doped polyimide structures have been determined to be effective OL materials for attenuating a power density of more than 1 J cm −2 in the IR range.

Spatial-energy, spectral, and optical characteristics of kilowatt supersonic cw HF chemical lasers of self-contained type with three-jet nozzle arrays using nozzle-nozzle-injector and nozzle-nozzle-nozzle configurations were experimentally studied. It was shown that such nozzle arrays enable one to form an active medium as long as 12.5 cm with a high optical quality. In a laser with a wide-aperture stable cavity, a laser beam with a nearly square cross section 11 × 10 cm in size was formed.

The transmission and scattering coefficients of the cavity mirrors were determined at the wavelengths λ = 1.3–1.4 μm typical of the radiation emitted by an overtone cw chemical HF laser. The results obtained were used to formulate the requirements in respect of the quality of the optics (the reflection and scattering coefficients) and to propose optical cavity configurations for lasers with the active medium 40 and 70 cm long. These formulations and proposals were verified experimentally. The experimental small-signal gain was used in a numerical analysis of the influence of the mirror characteristics on the output power and the emission efficiency of overtone lasers of the investigated type. The optimal reflection coefficients of the output mirrors were determined.

The process of writing thin amplitude-phase holograms in polyimide-based fullerene-containing conjugated organic media using an iodine laser operating at λ=1315 nm was studied. It is shown that such polymeric structures are promising media for reversible optical data recording in the IR spectral range.

The optical attachment for transformation the spatial characteristics of excimer laser has been experimentally investigated. The laser beam of rectangular section with sizes of 3 x 20 mm and divergence of 2 x 5 mrad after passage of an optical attachment got the square form 20 x 20 mm and equal divergence of 5 x 5 mrad orthogonal directions. It is shown, that application of such unit in the facilities for microprocessing of materials simplifies an optical path of illumination module, allows to receive the optimum uniformity of irradiation (within 2 %) at reproductive image with micron accuracy in plane of processed material and to mitigate the beam load on optical elements due to suppression of influence of "hot" points.

The two-channel optical circuit for measurement and the control of divergence of laser radiation over the sizes of the prints received in a plane of registration is considered. Analytical expressions for estimation of single and a solid angles and also for definition of divergence sign are presented. Experimental results are submitted. A few advantages are compared with the known circuit of a focal spot.

Results of research activity on development of basic technology for experimental nanolithographer with planned 10÷30 nm resolution are presented. The development circuits of illumination subsystem on base of laser produced plasma source and multimirror extreme ultraviolet reduced camera are analyzed. The manufacture technology of aspherical EUV mirrors with atomic-smooth surfaces and high-precision figure is considered. The illustrations of high-quality aspheric mirrors with supersmooth surfaces and an atomic level roughness are represented. The figure quality of 300-mm concave mirror and convex 120-mm mirrors of reduced camera measured by interferometry at l = 632 nm have been produced 0,008l rms and 0,005l rms respectively.

Now optical reducing systems for extreme ultraviolet projection lithography are being actively developed. Optical elements of these systems are required to be of super-high optical quality. For systems operating in the 13-nm wavelength range, their optical distortions should not exceed 1 nm in magnitude. Manufacturing of such elements with super-high optical quality requires large financial injections. In this report, we consider how to use thermal deformation of an optical element exposed to light for improvement of optical quality of the element. It is shown, in particular, that residual quasi-static large-scale (20% of diameter of the element) optical distortions, about 15 nm in magnitude, can be compensated with the proposed technique down to 0.5 nm (i.e. ≈ λ0/20 - λ0/30 for EUV).

The advantages of droplet and claster Li-contained targets for debris free EUV generation are estimated on base of analytical modeling and simulation. Conversion efficiency of laser energy into EUV energy from such targets is found to reach a few percents. The laser prepulse is proposed to enhance the laser energy conversion into emission at wavelength of 13.5 nm.

An optical limiting of the laser radiation over IR range in organic compounds based on polyimide has been studied. The non-linear transmission at a wavelength of 1315 nm as well as spectral properties of the compounds have been investigated. The result obtained have been explained by the donor-acceptor interaction mechanism that affects nonlinear- optical properties of organic molecules. The fullerene-doped polyimide structures have been determined to be effective optical limiting materials for attenuating a power density of more than 2 J cm2 in the IR range.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The optical limiting of the laser radiation over visible and IR ranges in organic material based on polyimide has been studied. The role of the donor-acceptor interaction mechanism in manifestation of organic molecules nonlinear-optical properties has been established. The fullerene-doped photosensitive polyimide structures have been determined to be effective optical limiting materials for attenuating a power density of more than 2 - 4 J(DOT)cm-2.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A possibility of the amplification of image brightness by the active medium of the photodissociative iodine laser have been demonstrated. The brightness of the test-object image with spatial frequency of 10 mm-1 was amplified 1600 times for Q-switch lasing action and 250 times for free- running one. The contrast of amplified image was equaled 0.8 in both occasions. The smallest input signal achieved the level of 10-13 J per pixel.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The results of an experimental research of action of the intensive mid IR-range pulse-periodic laser radiation on VO2-mirrors are represented. The damage thresholds of VO2-mirrors are defined for pulse-periodic and continuous radiation and the analysis of the mechanism of their destruction is carried out. The results of numerical simulation of dynamics of switching of VO2-mirrors under the action of pulse-periodic radiation are presented.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The possibility of the amplification of image brightness by active medium of the photodissociative iodine laser (PIL) have been shown. Brightness of the image grating with grid stroke of 10 mm -1 was amplified in 50 times at mono impulse lasing action and in 10* at free-running one. Contrast of amplified image as equal 0.8 in both occasions.

Numerical and experimental investigation on dependence of the output power P and radiation efficiency (epsilon) from the active medium composition and resonator characteristics was performed for an overtone supersonic cw HF laser. The optimal parameters of the active medium and of the dichroic mirrors for the device with the nozzle array length L equals 40...150 cm were determined. We obtained P approximately equals 8 kW and (epsilon) equals 43% in the experiment by L equals 70 cm. It has been established that the dichroic mirrors operated with a shot life time by energy density of 93 kW(DOT)cm-2.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Overtone supersonic cw HF laser with power density of about 8 kW is developed. Efficiency of the laser relative to emission of the main tone is about 40%. Coefficient of active medium gain measured by the technique of calibrated losses is (5.5 divided by 7.8)(DOT)10-4 cm-1. Designed wavelength- discriminating mirrors operated at power density of about 40 kW/cm2 (90 kW/cm2 in the maximum one-pulse regime). We suggest to use regenerative amplifying principle with application of ring conjugate resonator, having zero effective length, for design of adaptive laser-optical systems based on power lasers with very small gain.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The present work is the further evolution of our studies on wide-angle intracavity beaming in 3-10.6-micron gas lasers by space-time light modulators.

We have investigated the transient luminescence of silicate glasses irradiated with laser UV. The characteristic time of luminescence decay at room temperature is about 1 mks. We have found a dependence of the intensity and the spectra shape on geometry of irradiation and the sample thickness. We explain this dependence as a result of the luminescence radiation reabsorption with transient radiation defects. On this bases we have developed a model that gave us opportunity to calculate the transient absorption spectra, associated with that defect. These spectra significantly differ from stationary absorption spectra induced with multi- impulse irradiation.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A cw supersonic chemical HF laser with dichroic mirrors and external cavity has been investigated on the first overtone regime. The most intensive line P2-0(4) output power was greater than for any fundamental component.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper recording possibilities of non-stationary gratings in active medium of photodissociative iodine laser and using four-wave mixing for phase conjugation in its own medium were experimentally investigated for the first time.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

On base of coherent manganese vapor laser it was made high time-spatial resolved framing device. High speed framing registration has been used for the optical quality interferometric measurements in excimer and iodine lasers.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The R & D results of manganese vapor laser as light source for high speed framing registration are presented. The high spatial coherence of this laser have been achieved by using of a conjugate cavity. High reproducibility of the coherent characteristics was obser ved at pul se repeti U on up to I 01. keywords : manganese vapor 1 aser , spati al coherence , Fresnel numberanal og , conj ugate cavi ty I . I NTRODUCTI ON Combination of short duration Cr) and high repetition rate Cl) of light source pulses allows to realize the high speed framing with high time resolution. The spatial characteristic of frames isconsiderably determined by the coherence of light source. Among 1 1 ght sour ces of vi si bi e spectr urn r ange the manganese vapor laser with high repetition pulses rate, apparently, may insured high time and spatial resolution of the high speed framing. because of the full separated components of hyperfine spectrum str uctur e , narr ow 1 i newi dths C E=O. 02—0. 04 cm1)

The results of experiments on the nonlinear optical confinement of a pulsed 3.8–4.2 μm laser radiation in a composite comprising a silver-halide-based dielectric matrix containing dispersed silver nanoparticles are presented. It is shown that, for a laser pulse duration of 250 ns, the energy threshold for the laser radiation confinement is 5 mJ/cm2 and the dynamic confinement range exceeds 10.

We present results of R & D of an iodine photodissociative pulse-repetitive flash-lamp pumped laser with average power approximately 500 W and discuss some problems of its efficiency and scaling. The main problems are follow efficiency of lamp pumping, energetic efficiency of iodine laser, energetic possibilities of active medium and its optical quality, and the closed loop of active medium. In conclusion, the energetic possibilities of developed pulse repetitive laser are discussed, as are some prospects for the near future.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

When investigating the nonlinear transmission of fullerene-doped π-conjugate organic structures, it has been found for the first time that the broad-band light of a flashlamp has considerable impact on the optical limiting of infrared laser emission (λ=1315 nm).

Experimental data on the nano-and microsecond pulsed laser radiation (λ=1.315 μm) confinement in compensated GaAs are reported. There are three regions of confinement, which are controlled by radiation selfdefocusing due to single-photon absorption by deep impurity levels, self-defocusing due to two-photon absorption, and self-focusing caused by thermal dynamic lens formation.