PROBLEM TO BE SOLVED: To optimize light emission intensity for pulse wave detection in a photoelectric pulse wave sensor.SOLUTION: A light emitting part 11A radiates light to a living body, and the light having passed through the living body 2 of the radiated light is received by a light receiving part 11B. An operation part 32 derives pulse wave information (cardiac rate, etc.) on the basis of a pulse wave signal (V) according to intensity of the received light. When a pulse wave sensor is started, a light emission control part 34 causes the light emitting part 11A to emit light with test light emission intensity, and sets actual light emission intensity in the detection of a pulse wave using the detected intensity of the received light based on the light emission and predetermined reference intensity of received light. For example, the test light emission intensity is gradually increased until the detected intensity of the received light reaches the reference intensity of received light or higher, and the test light emission intensity at the time when the detected intensity of the received light has just reached the reference intensity of received light or higher is set to the actual light emission intensity.【課題】光電式の脈波センサにおいて、脈波検出用の発光強度を適正化する。【解決手段】発光部１１Ａは生体に光を照射し、照射した光の内、生体２を透過した光が受光部１１Ｂにて受光される。演算部３２は、受光強度に応じた脈波信号（ＶＢ）に基づき脈波情報（心拍数等）を導出する。脈波センサの起動時、発光制御部３４は、テスト発光強度で発光部１１Ａを発光させ、その発光に基づく検出受光強度と所定の基準受光強度とを用いて、脈波検出時における本発光強度を設定する。例えば、検出受光強度が基準受光強度以上となるまでテスト発光強度を段階的に増加させ、検出受光強度がちょうど基準受光強度以上となったときのテスト発光強度を本発光強度に設定する。【選択図】図４
