Pulse-wave-characteristic-point determining apparatus, and pulse-wave-propagation-velocity-related-information obtaining apparatus employing the pulse-wave-characteristic-point determining apparatus

An apparatus for obtaining pulse-wave-propagation-velocity-related information that is related to a velocity at which a pulse wave propagates in a living subject, the apparatus comprising:

• a pulse-wave detecting device which detects, as a first heartbeat-synchronous signal, a first pulse wave from a first prescribed portion of the subject;
• a pulse-wave modifying means for modifying a waveform of the first pulse wave detected by the pulse-wave detecting device, according to a predetermined relationship between first pulse wave, and second pulse wave whose characteristic point is clear;
• a characteristic-point determining means for determining a characteristic point of the modified waveform of the first pulse wave;
• a heartbeat-synchronous-signal detecting device which detects, from a second prescribed portion of the subject that is different from the first prescribed portion, a second heartbeat-synchronous signal;
• and
• a pulse-wave-propagation-velocity-related-information obtaining means for obtaining the pulse-wave-propagation-velocity-related information, based on a time of occurrence of the determined characteristic point of the modified waveform of the first pulse wave and a time of occurrence of a prescribed point of the second heartbeat-synchronous signal detected by the heartbeat-synchronous-signal detecting device.