FIELD: medical engineering; stomatology, otorhinolaryngology. SUBSTANCE: device has light-emitting diode 1, carrier-frequency power supply generator 2, photodiode 3, photocurrent amplifier 4, selective amplifier 5, envelope detector 6, DC amplifier 7, measuring instrument 8 and recorder 9. Light emitted by light-emitting diode 1 supplied from carrier-frequency generator 2 and positioned on one side of palate-throat valve, for example in oral cavity, passes through palate-throat valve repeatedly and while reflecting from its walls gets on photodiode 3, thus causing photocurrent in the latter proportional to integral illumination. After photocurrent is amplified by amplifier 4 variable electric signal arrives at selective amplifier 5 tuned to frequency of generator 2 which separates main harmonic of signal. Then signal is detected by envelope detector 7 and registered by recorder 9. Measuring instrument 8 is designed to check and adjust amplification. Multiple reflection makes photocurrent independent from individual features of route. When pronouncing phonetic sequence, palate screen rises, thereby limiting the light passage. In this case recorder indicates envelope the amplitude of which is proportional to value of area of palate-throat valve. Time of rise and fall of soft palate, when pronouncing different sounds and their combinations, can be judged by duration of envelope front. EFFECT: higher accuracy of measurements. 1 dwg
