eyepiece vs visual

eyepiece

noun
  • The lens (or combination of lenses) at the eye end of a microscope or telescope by which the image is viewed. 

visual

noun
  • Any element of something that depends on sight. 

  • All the visual elements of a multimedia presentation or entertainment, usually in contrast with normal text or audio. 

  • An image; a picture; a graphic. 

  • A preliminary sketch. 

adj
  • Related to or affecting the vision. 

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