Preparation Of Sulfur Based Chalcohalide Multispectral Glasses And Controllable Crystallization Treatment

In comparison with other infrared optical materials,chalcogenide glasses have wider infrared transmission waveband,well mechanical properties,higher nonlinearity,excellent thermochemical stability and capability of molding.Furthermore,their performances can be adjusted with the change of glass components.Therefore,chalcogenide glasses are of great application values in the fields of scientific research,industry,medicine and national defense.Multispectral glasses based on chalcohalide glasses are incorporated with the properties of chalcogenide and halide glasses,broadening their transmitted spectral into the visible waveband.In this thesis,based on before research results of chalcogenide and halide glasses,a new method has been developed to improve the properties of glasses through optimizing the compositions of chalcohalide glasses.Because of strong absorption displayed in the transmission spectra of the glass samples the appropriate purification schemes are designed for reducing the absorption bands.Through adjusting the technological parameters of thermal treatment the glasses with 30 centimeters in diameter are fabricated successfully.The crystallization properties of the glasses are also investigated in this work.In the first chapter,the background and significance of multispectral glasses are elaborated.The definition,classification,application,merits and drawbacks and research progress to date of multispectral glasses are introduced briefly.The properties of chalcogenide and chalcohalide glasses are compared.The contents and research methods of the thesis are also presented in the end of this chapter.The theories and methods used in this thesis are briefly reviewed in the second chaptersChapter 3 will set forth the novel dual halides co-doped chalcohalide methods for adjusting the properties of multispectral glasses.In chapter 4,the design and implement of new purification schemes are introduced.Chapter 5 discusses the fabrication of larger multispectral glasses.Through carefully exploring the technics parameters of fabrication,the glasses with 30 centimeters in diameter are fabricated with high optical quality.The multispectral glass samples are further heat treated in different temperature and time.The properties of glasses after crystallization are investigated in chapter 6.The conclusions of this thesis are presented in the last chapter.Some improving suggestions are also listed for the future research work.