PROBLEM TO BE SOLVED: To enable blood pressure measurement based on a pulse wave signal having suppressed distortion.SOLUTION: A blood pressure measuring method includes: first differentiating a pressure signal showing pressure including a variation caused by a pulse wave to generate a differential waveform； generating an integral waveform by starting integration of the differential waveform by detecting change of a sign of a value of the differential waveform at each of peaks of the differential waveform and ending the integration of the differential waveform by detecting re-change of the sign of the value of the differentiated waveform； detecting time T1 at which an increased value of the integral waveform reaches a first value and time T2 at which the value of the integral waveform decreased after the time T1 reaches a second value； and calculating pressure corresponding to strength of the pressure signal at the time T1 as first blood pressure and calculating pressure corresponding to strength of the pressure signal at the time T2 as second blood pressure.SELECTED DRAWING: Figure 4COPYRIGHT: (C)2019,JPO&INPIT【課題】歪みが抑制された脈波信号に基づいて血圧測定を行うことができる。【解決手段】まず、脈波による変動を含む圧力を示す圧力信号を微分して微分波形を生成する。微分波形のピークのそれぞれについて、微分波形の値の符号が変化したことを検出して微分波形の積分を開始し、微分波形の値の符号が再度変化したことを検出して微分波形の積分を終了することで積分波形を生成する。積分波形の値が増加して第１の値となる時刻Ｔ１と、時刻Ｔ１の後に積分波形の値が減少して第２の値となる時刻Ｔ２と、を検出する。時刻Ｔ１における圧力信号の強度に対応する圧力を第１の血圧として算出し、時刻Ｔ２における圧力信号の強度に対応する圧力を第２の血圧として算出する。【選択図】図４
