**5. Patents**

PL423097 (A1) PL233603 (B1), K. Olesko, A. Sobczyk-Guzenda, H. Szymanowski, S. Owczarek, Method for producing one-layered optical filters with the light refractive index gradient, 23 April 2019.

PL424592 (A1), K. Olesko, A. Sobczyk-Guzenda, A. Nosal, Method for supplying with vapours of the precursor of reactors intended for applying coatings by vacuum methods and the system for supplying with vapours of the precursor of reactors intended for applying coatings by vacuum methods, 26 August 2019.

**Author Contributions:** Conceptualization, H.S. and A.S.-G., methodology, H.S., K.O., and A.S.-G.; validation, K.O. and A.S.-G.; formal analysis, K.O. and A.S.-G.; investigation, K.O., H.S., M.F., A.S.-G., and J.K.; resources, H.S., K.O., and A.S.-G.; data curation, K.O. and J.K.; writing—original draft preparation, H.S. and A.S.-G.; writing—review and editing, H.S., A.S.-G., and M.G.-L.; visualization, H.S. and A.S.-G.; supervision, H.S. and A.S.-G.; project management, A.S.-G. All authors have read and agreed to the published version of the manuscript.

**Funding:** The research was founded by the National Science Centre (NCN), Poland, Grant No 2014/13/B/ST8/04293.

**Conflicts of Interest:** The authors declare no conflict of interest.
