Standards Development

Scope

This document defines the chalcogenide glass correctly from the perspective of chemical and specifies basic characterization and reporting method of chalcogenide glass used in the infrared spectral range from 0,78 m to 25 m.

Purpose

This document applies to the specification of the chalcogenide glass used in the infrared spectrum. The chalcogenide glass described in this document is transparent material in the infrared region. The chalcogenide glass has wide range of transparency from the visible to the infrared region depends on its chemical composition and variety of the refractive indices. This optical property can give flexibility or further capability to the IR optical system. And the machining easiness of the chalcogenide glass compared to IR crystals leads to not only high precision but also cost reduction. Furthermore, the chalcogenide glass can be applied to glass molding process taking advantage of its lower melting point Tm. It makes us to expect a high volume production with lower cost of infrared optical systems. For this process, the thermal mechanical properties such as lower glass transition temperature Tg, lower yielding point At and higher crystallization temperature Tc are preferred.

Nowadays, the chalcogenide glass is expected as a substitute material for the traditional infrared crystals like germanium, silicon or zinc selenide, and its markets are rapidly expanding. However, this new material is sometimes described with ambiguous words, and the unclear words confuse the user of optics market. In consideration of the rapid increasing of market for infrared application, the definition and standardization of the chalcogenide glass for infrared optics are necessary.

Because there are wide variety of items to be define and the standardization for the spectral bands in infrared region is in progress, the standardization of chalcogenide glass should be established step by step. In this document, important terms define what the chalcogenide glass and minimum required properties to report for optical design are specified as Part 1.