circle lens vs contact lens

circle lens

noun
  • Circle contact lens. 

contact lens

noun
  • A thin lens, made of flexible or rigid plastic, that is placed directly on to the eye to correct vision, used as an alternative to spectacles, or, if coloured, to change one's eye color cosmetically. 

How often have the words circle lens and contact lens occurred in a corpus of books? (source: Google Ngram Viewer )