## 5 Conclusions
This also allows reducing by many times the average laser power for the LFC of thick plates with a thickness of several millimetres. Thus, it enables reducing the depth of the heat-affected zone along the sidewalls of the separation. It is worth to note that the considered process of LFC of transparent materials is environmentally friendly since it occurs without the use of any technical liquids, abrasives, liquid or gaseous chemical etchants. Besides, when the filaments created in the material do not reach the front and/or back surfaces of the plate to be processed, there is practically no release of the material into the surrounding space in the form of vapours, droplets or solid fragments during the process. Conceptualization, V.N.T. and I.V.M. ; Formal analysis, V.N.T. and I.V.M. ; Investigation, V.N.T. and I.V.M. ; Methodology, V.N.T. ; Visualization, V.N.T. ; Writing--original draft, V.N.T. ; Writing--review & editing, V.N.T. and I.V.M. All authors have read and agreed to the published version of the manuscript. This research received no external funding. The data presented in this study  
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