Pronostic de défaillances basé l'nalyse vibratoire pour la maintenance des systémes mécaniques tournants

Abstract

Optical filters play an important role in all fields of science and technology. Optical filters are used to transmit spectral bands of determined width in a continuous spectrum or to isolate certain radiations in a line spectrum. In this work, we have simulated interference filters for a stack of several layers. These filters have been widely developed thanks to advances in thin film technology by vacuum evaporation on one side of the substrate or on both sides. We will limit our study to filters of schematic form (air/thin layer/sub). It is possible to obtain filters with wide or narrow band widths, in any region of the spectrum, with good transmittance and excellent optical quality. Use of a mathematical model based on the transmission of electromagnetic waves for interferential filters of schematic form (air/thin layers/substrate) allows to analyze the spectra of transmittance in a more rigorous way and to know what are the optimal conditions to build spectral functions such as: low pass, high pass, band pass