Visible Speech Translators with External Phosphors
Homer Dudley, Otto O. Gruenz · The Journal of the Acoustical Society of America · 1946
This paper describes some experimental apparatus built to give a passing display of visible speech patterns. These patterns show the analysis of speech on an intensity-frequency-time basis and move past the reader like a printed line. The apparatus has been called a translator as it converts speech intended for aural perception into a form suitable for visual perception. The phosphor employed is not in a cathode-ray tube but in the open on a belt or drum.