Zinc sulfide window

Anti-reflection (AR) coating with an adjustable index of refiactionfor germanium and zinc sulfide infiured windows. 

Abrasion and corrosion protection for germanium, magnesium fluoride, cadmium telluride, zinc sulfide, and zinc selenide IR windows. 

The most common IR window materials are zinc sulfide, which is translucent, and zinc selenide, which is transparent. Both of these materials are made by low-pressure CVD by the reaction of vaporized zinc and hydrogen sulfide or selenide (see Ch. 12). Germanium, another common IR window material, is also produced by CVD (see Ch. 8). 

Zinc Sulfide (ZnS, Irtran-2) 0.5-18 2.3 0,5 pm 2,0 18 pm ATR crystals, windows soluble in acids, slightly soluble in water... 

Be aware that cells made from nontraditional window materials, such as zinc selenide, zinc sulfide, germanium, or other medium to high refractive index materials, will usually result in the production of interference fringes, even in the presence of the sample. 

DLC coatings also have an opto-protective function, infrared window materials such as germanium, magnesium fluoride, cadmium telluride, zinc sulfide, and zinc selenide are rel h/ely soft and easily damaged and eroded by wind, rain, or particle impact. They have also poor resistance to corrosive environments. DLC coatings offer good protection with adequate optical properties. However, their narrow IR bandpass may limit the range of applications. 

Zinc sulfide is an important optoelectronic material which is useful as an infrared window and, when doped, as a phosphor, or as the basis for light emitting diodes (LEDs). Several works were carried out related to the preparation of zinc sulfide powder and films via sol-gel processing (Guiton, 1990 Donahue, 1998 Kavanagh, 2001 O Brian, 1998). Except for Route A, all other three routes were employed for the fabrication of zinc sulfide. 

Choice of Material for the Window. The material used for the window has to meet certain criteria. First, the wavelength range over which the transmission is satisfactory is important. The stability of the material in contact with the solution is also of importance (particularly for aqueous acid or alkaline electrolyte solutions). However, other parameters such as the refractive index, the hardness, the thermal expansion coefficient, the standard form in which the material is available, and even the price also influence its choice. Practically, for aqueous solutions, the selection is restricted to a few materials, including silicon, calcium fluoride, zinc sulfide, and zinc selenide. The main properties of these materials, together with those of KRS-5, KRS-6, and CdTe, are gathered in Table VI. Various examples of transmission curves are given also in Figure 21. 

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