adumbration vs optics

adumbration

noun
  • The form of an object as seen by an observer. 

  • The state of being in shadow or shade; (countable) a shadow. 

  • The outline of a charge (“image displayed on an escutcheon”), sometimes filled in with a darker shade than the field. 

  • A rough or symbolic representation; a vague indication of what is to come, a foreshadowing. 

  • A faint sketch; a brief representation, an outline. 

optics

noun
  • The physics of light and vision. 

  • Perception, image, public relations, especially in politics. 

  • The light-related aspects of a device. 

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