picturephone vs speakerphone

picturephone

noun
  • videophone 

speakerphone

noun
  • A telephone with a microphone and loudspeaker separate from those in the handset. 

  • A loudspeaker on a telephone that broadcasts the sound, to use handsfree. 

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