NUMERICAL SIMULATION OF THIN FILM CONDENSATION PROCESSES AND PRE-PRODUCTION ANALYSIS OF LINEAR VARIABLE FILTERS

Linear variable filters are one of the promising types of optical elements for creating multipurpose spectrometers. Application of this type of elements allows simplifying the optical scheme of the device significantly without great reduction of its characteristics. Using classical optical systems, linear variable filters improve the performance of optical devices. From the technology point of view, making this type of bandpass filter is a rather complex task. Current results of technology development of linear variable filters are considered in the article. In the course of work, a software was developed to calculate the distribution of condensed material on the substrate surface, taking into account the geometry of the source, substrate, masks and the whole system. Calculation of optical characteristics and analysis of the physical thicknesses of a linear variable filter were performed, and the dependence of the thickness of the coating on the coordinate of the substrate was obtained. The geometrical model for calculation was based on the geometry of the vacuum technological equipment – Advanced Optical Coater (VTE AOC), manufactured by IZOVAC Ltd. (Republic of Belarus). Based on the data obtained by using the software, the optimal geometry of the vacuum mask was proposed to obtain the required spectral gradient.

optics, filters, spectrometry, deposition, magnetrons, plasma, vacuum mask, numerical simulation

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