naked-eye vs visual

naked-eye

adj
  • Pertaining to the unaided eye, as in unaided sight. 

visual

adj
  • Related to or affecting the vision. 

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

  • Any element of something that depends on sight. 

  • An image; a picture; a graphic. 

  • A preliminary sketch. 

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