Sleep state estimation method using pulse wave and its application

Abstract

At present, 1 out of every s people in Japan experiences anxiety concerning sleep. We consider there are many people find it difficult to get up on time or find the experience of awaking unpleasant. We have developed a method of measuring variable indexes of pulse-to-pulse interval using pulse wave sensor, and a method of estimating the sleep states to reduce the influence of variation in the variable indexes to obtain frequency analysis of pulse-to-pulse interval due to circadian rhythm and the subject's condition. In this study, we describe a method for detecting change in sleep stage of a sleeping subject in real time, which uses variable indexes of pulse-to-pulse interval by pulse wave sensor, and we introduce a wake-up alarm application that is activated during change in sleep.