PROBLEM TO BE SOLVED: To judge stability regarding pulse wave measurement for each waveform by a smaller operation amount.SOLUTION: The pulse wave of a subject is detected, and the maximum value and the minimum value within a predetermined period of the pulse wave are detected. One or more reference values between the maximum value and the minimum value within the predetermined period are calculated conforming to one or more internally dividing ratios common to a plurality of predetermined periods of the pulse wave. Two or more times within the predetermined period at which the pulse wave intersects with either one of the one or more reference values are calculated. A time period between each calculated time in the predetermined period and a corresponding calculated time in a last period before the predetermined period is calculated as a pulse wave period of the pulse wave. A variation of the pulse wave periods is calculated for two or more pulse wave periods calculated between the predetermined period and the last period before the predetermined period. Then, stability of the measurement for the pulse wave period is judged based on the variation of the pulse wave periods by this pulse wave period measuring apparatus.COPYRIGHT: (C)2009,JPO&INPIT【課題】脈波計測に関する安定性をより少ない演算量にて各波形毎に判断すること。【解決手段】被験者の脈波を検出し、前記脈波の所定区間内における最大値及び最小値を検出し、前記脈波の複数の区間に共通の1つ以上の内分比に基づいて、前記所定区間内における前記最大値と前記最小値との間の1つ以上の基準値を算出し、前記脈波と前記1つ以上の基準値のいずれかとが交差するような、前記所定区間内における2つ以上の時刻を算出し、前記所定区間内における各算出時刻と前記所定区間の前の区間内における対応する算出時刻との時間間隔を、前記脈波の脈波間隔として算出し、前記所定区間と前記所定区間の前の区間との間で算出された2つ以上の脈波間隔について、脈波間隔のばらつきを算出し、前記脈波間隔のばらつきに基づいて、前記脈波間隔の計測の安定性を判断することを特徴とする脈波間隔計測装置。【選択図】図6
