Definition of optophone in US English:

optophone

noun

  • An instrument designed to enable a blind person to read, in which a photoelectric cell is used to scan a text and produce electric signals that are converted into audible ones corresponding to the different characters.

Origin

Early 20th century. From opto- + -phone, after German Optophon.

Pronunciation

optophone

/ˈɒptəfəʊn/