This paper presents an experimental research in the areas of knitting technology and optical fibres. The aim is to explore the possibilities to knit stiff monofilament optical fibres in flat knitting machines. The yarns used were transparent monofilament of polyester and optical fibres of PMMA (Polymethyl Metacrylate). Result shows that a hexagon shaped flat knitted prototype can be produced but also difficulties to knit monofilament yarn with optical fibres. The optical fibres was put into the structure in straight angles as weft insertion, to avoid bending and breakage of the monofilaments. Another problem was the take down device on the knitting machine but a solution of this is presented in the paper.