“…Tapered fibres are known to be compact and effective beam converters [1,2]. When used in fibre-fed spectrographs, they present a low-loss and compact alternative to other converters [2,3]. It is possible to heat and permanently stretch any fibre to narrow it down over a defined short length; thus, single mode (SM) fibres or multimode (MM) fibres can be tapered to meet the needs of a given application.…”