Yehorov S. Distortions compensation and parameters measuring of atomic emission spectra recorded by multi-element optical sensors

The purpose of the work is to investigate the mechanisms of distortions in image registration by multi-element sensors, develop methods for compensating errors in the registration of atomic emission spectra images, and propose methods for determining the parameters of spectral lines under conditions of signal noise and spectral line overlap. The object of research is the process of atomic emission analysis of elemental composition of substances and methods for its enhancement. Theoretical and practical results. An experimental setup has been developed and created for testing CCD (Charge-coupled device) sensors from Toshiba model TCD1304AP/DG under various temperature conditions, which are the most widely used in atomic emission spectrometers. The ISP-51 spectrograph has been equipped with an image shift system to finely shift the spectrum image by a fractional part of a pixel. A registration system has been established to capture the same spectral region, but charge shifting in the sensors occurs in the opposite direction. Additionally, software (SW) has been developed for spectrum registration, equipment control, results storage, data processing, and data output. Novelty of scientific results. The idea of using the features of the CCD sensor signal to measure temperature without the use of separate temperature sensors was developed, and this possibility was tested using the example of CCD sensors TCD1304AP/DG. Author's methodology for comprehensive compensation of CCD sensor non-linearities using temperature measurement without a sensor was proposed. The practical feasibility of expanding the dynamic range several times by utilizing the blooming effect, which was previously considered a negative phenomenon, was shown for the first time. An original approach to addressing the data incompleteness problem in increasing the resolution of multi-element sensors by shifting the image to a fractional part of a pixel using the characteristics of atomic emission spectra were proposed. A novel method for measuring the amplitude of spectral atomic emission lines using prior knowledge of the spectrometer's hardware function and emission frequencies, employing the maximum likelihood method, was proposed. Research methods are based on the general theory of mathematical result processing, while electronic and optical devices are designed using theoretical calculation methods and computer-aided and experimental modeling. Statistical methods for noise parameter estimation were also employed. Empirical Bunsen-Roscoe reciprocity principle was used to assess the linearity of photosensitive sensors, involving the interchangeability of exposure and irradiation intensity. Degree of implementation. The results of the work have been implemented in numerous Ukrainian enterprises. Scope of use. The developed processing methodology can be utilized in spectral line intensity analysis.