| The band of near,middle and far infrared light includes 1-3?m,3-5?m,8-14?m atmospheric windows,covering many important characteristic spectra.Therefore,the band of light-emitting materials has a wide application prospect in biomedical,satellite remote sensing,weapon guidance,industrial processing,weapon penetration and other fields.As the key material of fiber communication and fiber laser,the near mid infrared light-emitting materials are mainly produced by rare earth ion doped light-emitting,semiconductor light-emitting and non-linear light-emitting,among which rare earth ion doped light-emitting has been playing a leading role in the field of near mid infrared light-emitting.The rare earth ion doped luminescence is a kind of non-equilibrium radiation.The matter needs to be stimulated outside and deviated from the original thermal equilibrium state,and finally released in the form of light.In the near mid infrared luminescent materials,the doping of Ho3+,Er3+,Tm3+rare earth ions has been studied more.Through its energy level transition,Ho3+ions can emit at 1.2?m,2.0?m,2.85?m,Er3+ions at 1.55?m,2.7?m,Tm3+ions at 1.8?m and2.3?m.It can be seen that all the three rare earth ions emit light near 3?m,but the area near 3?m belongs to the strong absorption range of water vapor,so the water in the form of hydroxyl in the glass will have a certain impact on the luminous efficiency of this band.Therefore,it is of great significance to study the reduction of hydroxyl content in glass matrix for the realization of rare earth ion doped near and mid infrared radiation.In addition,as the key material of weapon infrared countermeasure,the medium and far infrared band luminescent materials radiate mainly in the way of heat balance,mainly in the way of chemical reaction heat and electric heating.At present,the research on this field is mainly focused on the chemical reaction heat.The combustion and explosion of lighting agent,thermite,magnesium polytetrafluoroethylene,yellow phosphorus,condensed solid gasoline and other combustion agents are used to release strong mid far infrared radiation.However,this radiation mode always has uncontrollable radiation spectrum characteristics,uneven radiation intensity,uncontrollable duration,and it is difficult to achieve profiling effect.With the maturity of infrared guidance technology,target characteristic spectrum has been identified.Therefore,it is very important to develop a kind of radiation material and device with high radiation intensity,stable and adjustable spectral characteristics,controllable duration and shape simulation in the middle and far infrared band for the construction of national defense weapons.Because the near mid infrared light-emitting belongs to non-equilibrium radiation and the mid far infrared light-emitting belongs to equilibrium radiation,this paper introduces the basic theory and related research progress of the two materials in the introduction part,and discusses the methods of enhancing the luminous efficiency.In Chapter 3,4 and 5,the preparation methods of enhanced near-and far-infrared light-emitting materials are introduced.In Chapter 6,the methods of enhanced mid-and far-infrared radiation and the characterization of infrared radiation spectrum of unit devices and Simulation prototype are introduced.The specific work is as follows:(1)In Ho3+ion doped tellurite glass(58Te O2-5Na2CO3-35Pb O-Ho2O3-Yb2O3),different content of halides(Pb Cl2?Pb Br2?Pb I2)were gradually replaced Pb O,in which chloride ions,bromine ions and iodine ions were chemically reacted with hydroxyl groups in glass matrix.By FT-IR and luminescence spectrum,it was found that introducing appropriate amount of halide can obviously increase the transmittance of glass in about 3?m,and the near-middle infrared luminescence intensity was also enhanced,which proved that halide has the effect of dehydroxylizing in glass matrix.The effect of halide introduction on the near-infrared luminescence properties of Ho3+tellurite glass was analyzed by absorption spectroscopy and J-O theoretical calculation.The gain bandwidth of the calculated Pb Cl2 substitution content of 35 mol%glass at1.2 and 2.0?m was about 36.661×10-27 cm3 and 185.6×10-27 cm3,indicated that the chlorine-doped tellurite glass has excellent gain effect for near-infrared and mid-infrared amplifiers.(2)In Er3+ion doped tellurite glass(67.5Te O2-10Pb F2-10Pb O-5YF3-5Na F-1Er F3-1.5Yb F3),different content of Pb(NO3)2 was used instead,in which nitrate ion acts as clarifier in glass melting process decomposition to produced bubbles could take away the water gas in the glass matrix,and decomposed nitrate ion could produce free active oxygen ion,the oxygen ion could reaction with hydroxyl group and produced water through chemical method,so the combination of physical method to dehydroxy group and chemical method to dehydroxy group finally made the content of hydroxyl group in glass matrix significantly reduced.The experiments shown that 0.6 mol%doped Pb(NO3)2 has the best optical properties,and its gain bandwidth was about 75.1×10-27cm3 and 79.1×10-27 cm3,respectively,in the 1.5 and 2.7?m band bands,indicating that the introduction of nitrate can made the glass matrix better used in the near-mid-infrared laser gain materials.(3)Using different contents of Ag NO3 to replace Pb O,nitrate ions in the glass matrix in Tm3+doped silicate glass(50Si O2-45Pb F2-5Pb O-2.5Tm F3),the effect of reducing hydroxyl concentration was achieved by chemical and physical methods.In addition,the nano-silver particles obtained by annealing the glass samples played an energy transfer effect in the glass matrix,which further enhanced its near-mid-infrared luminescence intensity.The results shown that the maximum emission cross-section values of the samples containing nano-silver particles at 1.8?m and 3.8?m were increased to varying degrees,and the values had reached 0.7831×10-20 cm2 and0.2774×10-20 cm2,and the positive gain appears when the particle population coefficient P>0.4.So the introduction of nano-silver particles made the glass system have good near-infrared and mid-infrared light gain performance.(4)In the aspect of mid far infrared ceramic materials,by adjusting the reaction time of hydrothermal method and introducing the active agent,the ceramic materials with regular morphology and uniform particle size distribution were finally prepared,and the emittance of the materials in the 3-5?m and 8-14?m bands were above 0.9.On this basis,the high emissivity infrared radiation material,flexible matrix material and heating source were fabricated by hot pressing method.The experimental results show that the spectral characteristics of all the unit devices were consistent with the infrared radiation materials,and the infrared radiation intensity can be controlled in real time by adjusting the input current.The assembly scheme of the assembly device was implemented according to the theoretical calculation.The results of the infrared thermal imaging test proved the effect of the full profiling,and got the infrared radiation intensity at different bands through calculation. |
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