Application of the spectral selection method for analyzing spatial inhomogeneities in scattering and luminescent materials

   Purpose of research. Testing of the spectral selection method using narrow-band interference filters for the analysis of spatial inhomogeneities in light-scattering and luminescent media using the example of astrophysical objects of various nature.

   Methods. The studies were carried out using a specialized optical complex based on a cooled color CCD camera QHY 533c and selective interference filter Svbony SV220 (Hα and OIII lines). Two optical schemes were used: a wide-field configuration with a 200 mm f/4 telephoto lens for studying large-scale structure, and a high-resolution configuration with an Askar FRA 500 astrograph (500 mm f/5.6) for detailed morphology analysis. Specialized software with implemented algorithms for photometric calibration and mosaic composition was used for data processing.

   Results. For the luminescent medium (IC 1805), a spatial resolution of ~0.04 pc/pixel was obtained, which made it possible to identify structures tens of thousands of AU long and estimate the dynamic pressure of the stellar wind (~10^-11 Pa). For the light-scattering medium (LBN 667), a resolution of ~600 AU/pixel was achieved, which ensured the identification of fibrous structures of substellar scale (< 0.1 pc). The method's capability for selective mapping of various environment components with contrast > 90 % has been demonstrated.

   Conclusion. The spectral selection method demonstrates high efficiency for diagnosing spatial inhomogeneities and can be adapted for solving materials science problems, including the analysis of luminescent coatings, defect control in transparent media, and non-destructive testing of multilayer structures. The development of specialized interference filters for specific technological applications is a promising direction.

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