指輪型バイタルサインモニタの試作

抄録

A telemetry system was developed to monitor a vital sign of the person who needs continuous monitoring. To make a long-term monitoring possible, a transmitter was made small and wearable as a finger-ring. As a vital sign, a photoplethysmographic signal is detected at the finger on which a ring-type telemeter is worn. The signal is sampled, and is transmitted to a receiver using a radio wave. At the receiver, the signal is demodulated into cardiac pulses. Then, the rate and the amplitude of the pulses are monitored continuously. If the pulse interval falls out of a predetermined range, or becomes undetectable, an alarm system is activated. The alarm system informs the emergency by an alarm sound or by automatic emergency call. A test-system was manufactured. It was as small as an ordinary ring, and easy to be worn all day long. The fundamental functions of this system were examined, and its performances were satisfactory.