Chalcogenide glass with good thermal stability for the application of molded infrared lens

Abstract

An interest of chalcogenide glass has been increased because of their use in preparing optical lenses in range of 3-12 μm.With recent advance in less costly uncooled detector technology, moldable lens using chalcogenide glass has drawn a great deal of attention. In this study, amorphous Ge-Sb-Se chalcogenide was prepared by a standard melt-quenching technique. Melted chalcogenide glass for moldable lens should have unique thermal and mechanic properties in order to be applied to molding process. Specifically, the Ge:Sb ratio were controlled in order to find out the most stable glass forming area. Thus, the optical, thermal and thermomechanical properties to find out the specific composition were characterized by FT-IR spectroscopy, Differential Scanning Calorimeter and Thermo Mechanical Analysis, respectively. The moldability of chalcogenide glass was characterized through the surface condition of glass samples. Finally, the preferential Ge:Sb ratio in Ge-Sb-Se based chalcogenide glass system was selected to fabricate moldable lenses.

Comparison of Lateral Crystal Growth in Selenium Thin Films and Surface of Bulk Samples

“…Knowledge of the overall crystallization behavior and its subprocesses (nucleation and crystal growth) is very important for preparation, processing, storage, and application of amorphous materials. It is important to consider crystallization from two points of viewavoiding formation and subsequent growth of crystals leads to formation of an ideal and stable glass or to preparation of glass fibers. , On the contrary, some applications of modern materials are based on a controlled amorphous-to-crystalline transformation (e.g., modern phase-change materials, , preparation of glass-ceramics , ). Description of crystal growth and nucleation over a wide temperature range as well as comparison of these processes in different forms of the material (bulk, fiber, thin film) can then provide important information for tailoring and optimization of new high-tech materials or for prediction of crystallization behavior in materials with similar physical properties.…”

“…Knowledge of the overall crystallization behavior and its subprocesses (nucleation and crystal growth) is very important for preparation, processing, storage, and application of amorphous materials. It is important to consider crystallization from two points of viewavoiding formation and subsequent growth of crystals leads to formation of an ideal and stable glass 1 or to preparation of glass fibers. 2, 3 On the contrary, some applications of modern materials are based on a controlled amorphous-to-crystalline transformation (e.g., modern phasechange materials, 4,5 preparation of glass-ceramics 6,7 ).…”

Stress Relaxation and Refractive Index Change of As2S3 in Compression Molding

“…Chalcogenide glasses have seen increasing applications in infrared detectors, moldable optics, and optical fibers, because of their wide range infrared transmission, high refractive index, high nonlinearity, and low phonon energy. In addition, chalcogenide glasses can be readily molded into precision optics, therefore providing photonics industry with material candidates for low cost and high‐performance photonic devices. In compression molding process, a softened glass blank is compressed to the desired shape at temperature slightly above its glass transition temperature.…”