Optopalatograph (OPG): a new apparatus for speech production analysis

Describes the early development of a device for measuring tongue-palate distance, contact and pressure across the whole of the hard palate. The optopalatograph (OPG) is similar in principle to the glossometer and similar in configuration to the electropalatograph. It uses optical fibres to relay light to and from the palate and distance sensing is achieved by measuring the amount of light reflected from the surface of the tongue. This paper compares the performance of an optical-fibre-based OPG sensor with that of the direct glossometer configuration and demonstrates improvements in accuracy and sensitivity