Etsunori Fujita,Yumi Ogura,Shinichiro Maeda,Shigeyuki Kojima
申请号:
US13266188
公开号:
US20120101395A1
申请日:
2010.04.24
申请国别(地区):
US
年份:
2012
代理人:
摘要:
A state change of a person is captured with timing closer to consciousness of the person. A frequency slope waveform of a time series signal of a pulse wave of a body of a person detected by an air pack is obtained by a frequency slope time-series analyzing and a computing device and a frequency fluctuation time-series waveform is obtained by a frequency fluctuation time-series analyzing and computing device. By comparing changes of two waveforms with each other in a waveform determining device, a state change of a person can be captured with timing closer to consciousness of the person. A sleep-onset point can be specified clearly based upon the case where a fluctuation waveform steep gradient portion indicating a steep gradient change emerges in the frequency fluctuation waveform, and amplitude and a base line position of the frequency fluctuation waveform or the frequency slope waveform are in predetermined ranges. Further, when a mean slope line of the fluctuation waveform steep gradient portion is approximately parallel to a mean slope line of the slope waveform steep gradient portion in the frequency slope waveform before emergence of the fluctuation waveform steep gradient portion, a sleepiness waveform is determined, so that a sleepiness state leading to sleep onset can be detected.