fibreglass vs optical fibre

fibreglass

noun
  • A composite material made from fine fibres of spun glass held together with resin. 

  • Silica based glass extruded into fibers that possess a length at least 1000 times greater than their width. 

verb
  • To apply fibreglass to. 

optical fibre

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

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