Critical Values Determination of Parameters of Fixed Electron Flows System in the Processing of Oxide Coatings on Extended Optical Elements.

A mathematical model has been developed for the external uniformly distributed thermal effect on the surface of a flat bilayer element made of optical glass K108 and oxide coating with Al₂O₃, MgO, taking into account the temperature dependencies of their thermophysical properties (volumetric heat capacity and thermal conductivity). Critical values of external thermal impact parameters (heat flows and durations of their action) leading to the destruction of coatings (crack formation, detachment, delamination, etc.) have been determined. The problem of implementing a uniformly distributed thermal effect along the surface of the oxide coating using a system of fixed ribbon electron flows (REF) has been solved. These REFs are incorporated as a programmatically controlled module into the equipment of modern electron-beam devices. Permissible processing regimes for coating surfaces have been defined (the number of REFs, controlled parameters for each REF such as current, accelerating voltage, and distance to the processed surface). These regimes allow to improve their operational characteristics and prevent potential damage under extreme operating conditions of devices (elevated heating temperatures, thermal shock effects, etc.). Electron-beam processing of extended elements made of optical glass and ceramics, piezoceramic elements, as well as optical elements with coatings of metal oxides, is considered potentially capable of qualitatively processing their surfaces using a system of fixed REF. These REF can serve as the elemental basis in microoptics, integrated and fiber optics, functional electronics, and other fields of precision instrument engineering. [ABSTRACT FROM AUTHOR]