To provide a vascular pulse wave measuring system capable of obtaining respiratory fluctuation with large amplitude and high accuracy as compared with the conventional art.An optical probe including a light emitting element and a light receiving element for receiving reflected light from a blood vessel or light transmitted through a blood vessel through the skin, and a light emitting element is driven based on an input drive signal What is claimed is: 1. A vascular pulse wave measurement system for performing a vascular pulse wave measurement using an optical transducer circuit including a drive circuit and a detection circuit for converting the light received by the light receiving element into an electric signal and outputting the electric signal, Measuring means for generating a self-oscillating signal from the detecting circuit by synchronously feeding back the signal as a driving signal to the driving circuit and measuring the self-oscillating signal as a blood vessel pulse wave signal And control means for controlling at least one operating point of at least one of the detection circuit and the drive circuit so that the level is substantially maximized, characterized in that the vascular pulse wave signal measured by the measuring means is subjected to amplitude demodulation by doing To detect the absorption change.(FIG.【課題】呼吸変動を従来技術に比較して大きな振幅でかつ高い精度で得ることができる血管脈波測定システムを提供する。【解決手段】発光素子と血管からの反射光又は血管を介した透過光を皮膚を介して受光する受光素子とを含む光探触子と、入力される駆動信号に基づいて発光素子を駆動する駆動回路と、受光素子により受光された光を電気信号に変換して出力する検出回路とを備えた光探触子回路を用いて血管脈波測定を行う血管脈波測定システムであって、電気信号を駆動信号として駆動回路に直接に同期帰還することで、検出回路から自励発振信号を発生して、当該自励発振信号を血管脈波信号として測定する測定手段と、自励発振信号のレベルが実質的に最大となるように、検出回路及び駆動回路の少なくとも一方の動作点を制御する制御手段とを備える血管脈波測定システムにおいて、測定手段により測定された血管脈波信号を振幅復調することで呼吸変動を検出する。【選択図】図22
