fibre optics vs optical fibre

fibre optics

noun
  • The transmission of light through fine flexible glass or plastic fibres, especially as a medium for communications networks. 

optical fibre

noun
  • A thin, transparent, flexible fibre, made of glass or plastic, used for transmitting light. 

How often have the words fibre optics and optical fibre occurred in a corpus of books? (source: Google Ngram Viewer )