laser vs optical maser

laser

verb
  • To cut with a laser. 

  • To throw or kick with laser-like precision. 

noun
  • A laser printer. 

  • A device that produces a monochromatic, coherent beam of light. 

  • Such a plant. 

  • A gum resin obtained from certain umbelliferous plants. 

  • A beam of light produced by such a device; a laser beam. 

optical maser

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