atomizer vs vaporizer

atomizer

noun
  • An instrument for reducing a liquid to spray or vapor for disinfecting, cooling, medical use or perfume spraying. 

vaporizer

noun
  • A device with a heating element, used to vaporize a liquid. 

  • A device with a heating element, used to vaporize a liquid solution with medicine. The produced vapor condensates into fine aerosols, forming a mist inside the device, to be inhaled by the patient for delivery of the medicine into the lungs. 

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