The document discusses the functions of an industrial yarn quality monitoring system, including: 1) Indicating faulty spinning units on a machine to enable quick technical examination and improve production quality. 2) Measuring yarn count, unevenness, and imperfections to provide quick and detailed quality information. 3) Analyzing yarn through additional metrics like spectral analysis to further characterize quality and defects. 4) Exporting data files for additional off-line analysis and processing of results.