Optical Multichannel Multispectral Radiation Monitoring Sensor System for Aircraft Engines

A scheme of an optoelectronic sensor is proposed that implements multichannel narrowband reception in those spectral regions that allow determining the presence of increased concentrations of iron, copper and carbon dioxide in the flame of aircraft engines. Two variants of the optical system design have been proposed, which implement spatial-frequency selection for electromagnetic waves emitted by a torch, allowing changes to be recorded only at frequencies that correspond to radiation peaks occurring in the presence of certain metals or gases. In the first scheme, each narrow-band optical reception channel consists of a lens and an additional optical system formed from narrow-band multilayer thin-film interference mirrors that implement frequency filtering of recorded signals for a given wavelength. In the second scheme, one input lens is used, and the separation of reception channels is carried out by a system of mirrors that specify different paths of optical radiation propagation for selected wavelengths, at which the radiation intensity changes most strongly when solid particles Fe or Cu are emitted from the surface of engine components, or when the concentration of CO2 changes. In the course of the study, interference narrowband selective systems were synthesized to isolate sub-bands in both the ultraviolet and infrared regions of the spectrum and their spectral optical characteristics were obtained.