The results of a study of a pulsed short-arc unlimited high-pressure xenon discharge as a source of UV radiation are presented. A theoretical analysis of the possibility of increasing the efficiency of xenon discharge radiation in the UV region of the spectrum is performed, the design of a three-electrode flash lamp is described, and the electrical, brightness and spectral characteristics of the source being developed are studied.

The paper presents results of research aimed at improving the serial pulsed sources of the IR-radiation based on a discharge in the cesium-mercury-xenon vapor mixture. To create the environmentally friendly gas-discharge source and increase the peak radiation strength, it proposes to replace the mercury buffer in a serial lamp with the rubidium vapor. Based on the thermodynamic analysis, necessity of using cesium as the main component in the plasma-forming medium of IR-radiation pulsed sources was proved. It was established that introduction into the cesium discharge of less than the 25 % (wt.) rubidium provided the required cesium vapor pressure and the plasma thermal conductivity. It was shown that the mass of the alloy with cesium played an important role in the discharge transition from unsaturated to the saturated vapors. Comparison results are presented in peak intensity of the studied IR-radiation gas-discharge lamps depending on amplitude and duration of the supply voltages in the repeated pulsed mode. A technique was developed to compare energy efficiency of the discharges under study, and the spectral research was performed confirming advantages of the IR-radiation pulsed source based on the cesium-rubidium-xenon discharge by the serial gas-discharge lamps

Based on the results of computational and experimental studies, it is shown that the use of a cesium–rubidium alloy as a plasma-forming medium in serial pulsed sources of IR radiation is promising. It was found that at a 25

The paper presents main results of investigating electrical parameters and characteristics of the pulsed xenon lamp ultraviolet radiation with a U-shaped plasma channel and caprod current leads. The gas-discharge lamp design feature suggests presence of the ballast transelectrode volumes contributing to the xenon escape from the discharge and the radiation acting from one part of the U-shaped plasma channel on the other. Literature sources devoted to the specified phenomena were analyzed. Factors influencing the xenon plasma thermophysical state were established. Due to the lack of techniques for registering the pulsed radiation in a narrow spectral range of 200--300 nm, measurement techniques and investigation hardware were considered in detail. The time interval for establishing the gas-dynamic equilibrium in a pulsed xenon lamp in the process of its entry into the nominal operating mode was determined by calculation and experiment. Studies of the Vt transelectrode volume effect on characteristics of the pulsed xenon plasma were carried out in the range of 0.16 < Vt /Vi < 0.3. It was established that the possible factors leading to a decrease in the current density and intensity of the UV radiation included the modes of electrical supply and evaporation of the quartz shell limiting the discharge. It was shown that self-radiation return in plasma contributed to an increase in the current density of the pulsed xenon lamp

The paper is dedicated to the study of the formation of a high-current stage of a pulsed discharge in cesium vapor from a continuously burning auxiliary plasma channel. The comparison of the electrophysical parameters and the radiation characteristics of a pulsed discharge in the presence and absence of an auxiliary discharge was carried out. Recommendations for choosing the parameters of the auxiliary discharge power supply to ensure the stability of radiation pulses in the pulse-periodic structure of output signals of optoelectronic systems were given.

The аrticle is devoted to the study of the possibility of creating an environmentally friendly source of radiation in the mid-infrared range of the spectrum. Chemical elements suitable for replacing mercury in the pulsed gas-discharge lamps plasma channel were theoretically analyzed. On the basis of a mathematical model, the effect of an additionally introduced component on the cesium vapor pressure and the thermal conductivity of the plasma-forming medium was revealed. In the paper, experimental studies confirming the technical solution validity for replacing mercury with rubidium were carried out, and practical recommendations were given on the weight ratios of the components introduced into the discharge.

An analysis of the radiation from cesium lamps has shown that the spectrum of such lamps is determined by the recombination continuum. This spectrum is close to the spectrum of the Sun not only in the visible, but also in the ultraviolet in the A and B ranges. This makes it possible to create environmentally friendly energy-efficient lighting systems with constant UV radiation based on these lamps to compensate for the lack of ultraviolet radiation at high latitudes and when working indoors without natural light. The advantages of such systems are considered in comparison with existing dual systems using conventional visible light sources and special erythemic fluorescent mercury lamps.

The paper presents the results of studies of the influence on the optical transmission of defects in the structure of a sapphire tube grown by the method of A.V. Stepanov, changes in the transparency of a single crystal after mechanical surface treatment, and ultraviolet and radiation exposure.

The article considers the design and technology features of cylindrical soldering of sapphire (corundum) with niobium and kovar alloy (alloy 29NK), developed for use in flash lamps with a discharge in alkali metal vapors. The performance of a gas-discharge lamp is analyzed and the basic requirements for the junctions are determined. The main types of defects determining the optical transparency and mechanical strength of a corundum monocrystal grown by directional crystallization the Stepanov method are shown, and the main requirements for a profiled sapphire tube are formulated. The results of internal stresses reduction studies during heat treatment of a corundum pipe before soldering are presented. The special attention is paid to the study of physicochemical phenomena occurring in the process of soldering sapphire with niobium using glass-ceramic solder and with kovar copper. It is proved that for the soldering corundum with niobium it is necessary to introduce up to 1 % zirconium impurity into the metal structure, which allows reducing the recrystallization of the alloy and decreasing the migration rate of the formed grains. In the case of active soldering sapphire with kovar, the importance of observing the recommended temperature regimes for melting solder to prevent the formation of titanium intermetallic compounds is shown. The main design solutions of sapphire soldered joints and the results of their tests for resistance to mechanical and climatic factors are given

The paper presents the results of a study of pulse-periodic discharge cesium lighting lamps with discharge tubes 5 mm in diameter and an interelectrode distance of 55 and 22 mm. The cesium pressure varied from 10 to 750 Torr at a constant triangular current pulse with an amplitude of 80 A. It is shown that the maximum of the luminous efficacy (~ 65 lm/W) corresponds to a pressure of ~ 130 Torr. It was found that a discharge column in the long tube at a pressure of ~ 300 Torr contracted into a bright pinch with a diameter close to that of the electrodes (2 mm). The pinch was localized along the surface of the tube and moves randomly on it. Contraction leads to a repeated increase in the luminous efficacy with pressure up to ~ 70 lm/W. Wall stabilization limits the plasma temperature on the axis of the pinch (it was found from the recombination continuum) to the level of 6000 – 6500 K. The column in short tube is localized along the axis of the tube over the entire power range. The temperature in it quickly rises to 13000-– 14000 K after the maximum of the luminous efficacy.

A pulse-periodic cesium discharge is studied in a wide range of its parameters in two lamps with burners of the same diameter (5 mm), but with different interelectrode spacings (55 and 22 mm). It is found that such a decrease in the length of the plasma column leads to a significant change in the properties of the discharge. In the longer burner, contraction of the discharge column occurs as the pressure increases with the localization of the plasma column at the wall of the discharge tube, and a significant increase in lamp efficacy is observed with a further increase in pressure. In the shorter burner, contraction occurs at lower pressures (specific powers) with the localization of the plasma column along the tube axis, and there is no increase in lamp efficacy with a subsequent increase in pressure.

The work is devoted to the study of thermophysical and radiation processes during the formation of a plasma channel under the passage of a series of current pulses of pulsed-periodic cesium–xenon–mercury discharge. The influence of the auxiliary discharge mode, temperature, and vapor pressure of metals on the development and relaxation of the plasma channel is shown. The spectral characteristics of the passage of each of the current pulses are studied.

ABSTRACT In the present work, the results of the research gas discharge lamp constructive elements those made from niobium and zirconium alloy, sealing by means of melting titanium with its alloy with nickel are presented. It is performed construction peculiarities analysis of gas discharge lamp with sapphire shell. The requirements to sealing materials are formed. It is studied physical and chemical processes occurring in materials during lamp sealing and lifetime.

The processes occurring in glass-ceramic solders of sapphire-niobium seals, used as current lead-ins in gas-discharge lamps with a discharge in alkali-metal vapor, were studied. The structural changes occurring in the glass-ceramic solder, based on the system of oxides CaO–Al2O3 and CaO–MgO–Al2O3, upon heating to 1600°C with niobium diffusing into the melt, are analyzed on the basis of x-ray phase analysis of the composition and a study of the microhardness.

This article describes the major development results of the first Russian sample of a UHP xenon discharge lamp with sapphire envelope. The article proposes a method of monitoring of thermal fields of semi-transparent materials and studies the thermal distribution of quartz and sapphire envelopes of UHP discharge lamps. Mechanical strength of sapphire tubes depending on the temperature is studied, the thickness of the discharge envelope wall is calculated, and distinctions of the design of a UHP xenon lamp with the sapphire envelope are considered.

The factors that determine the two most important characteristics of powerful infrared radiation sources, peak power and the depth of the radiation modulation in the spectral regions 1.8-4.2m and 3.0-5.0m, are investigated.The distributions of temperature fields in the discharge channel and in the system of two sapphire shells separated by a gap with the gas are given.It is shown that in the pulsed-periodic mode of operation with a pulse repetition rate of 450 Hz, the temperature field in the heated shells is practically stationary and causes, at high electric powers, the appearance of a constant radiation of the material of shells.As a result, the fraction of the discharge radiation in the total radiation of the source decreases, which negatively affects the depth of modulation.The temperature drop over the wall thickness is much smaller than the temperature difference in the gas gap.Data on the time dependence and the structure of heat losses on the inner shell are given.The spectral dependence of the depth of modulation is obtained under conditions of different cooling intensities, it is established that starting from about 4.9-5.2m, the lamp practically loses modulation properties in the infrared region.In this case, a sharp decrease in the depth of modulation begins from wavelengths of about 3.5 μm.The methods and design solutions that contribute to the increase of the modulation depth due to the reduction of the constant component of the radiation and the increase in the peak power of the radiation are considered in detail.The results obtained make it possible to reduce the laboriousness of experimental work in designing devices of this type Radiation source shell, temperature field, modulation depth

The paper is devoted to the study of changes in characteristics of ultra-high pressure short-arc xenon lamps when a tungsten layer is sprayed onto the quartz shell, as a result of heating and local electrode erosion. The paper analyzes the mechanisms of phenomena occurring in the super-high pressure xenon discharge and the cathode spot, which affect the sputtering of the electrode material. The main negative effects of tungsten deposits appearing on the lamp shell inner surface are considered: a decrease in the optical transparency and mechanical strength of quartz glass, an increase of the bulb temperature, a change in spectral characteristics and spatial distribution of radiation of a gas-discharge lamp. The original method developed for studying the parameters of radiation of a gas-discharge lamp and based on the superposition of the optical axis of the photometer with the axis of the lamp passing through the cathode spot and the considered shell segment, transparent or sprayed, allowed us to compare radiation characteristics of the lamp without changing the plasma parameters. The thermodynamic analysis carried out within the research confirmed the absence of chemical interaction of tungsten layer with quartz glass. Spectral distribution of xenon discharge radiation in the visible and IR ranges is different for a transparent bulb and the bulb with a tungsten spot, which is due to the size of tungsten layer particles on the lamp bulb. A study of spatial distribution of radiation from a gas-discharge lamp showed a decrease in the intensity of radiation in a solid angle bounded by a tungsten spot. At the same time, in this region, there was observed an increase in the temperature of the quartz shell, leading to the appearance of a longitudinal gradient of the temperature field of the gas-discharge lamp.