PULSE PHOTOMETER

摘要

A pulse photometer includes a light emitter, a light detector, a first signal separator that separates a first signal component and a first noise component, a second signal separator that separates a second signal component and a second noise component, a first determining section, a second determining section, and a concentration calculating section that calculates a concentration of a light absorption material in blood of the subject based on a fundamental frequency of the first signal component or a fundamental frequency of the second signal component.

主权项

1. A pulse photometer comprising:
an emitter that emits at least three kinds of light beams at different wavelengths; a detector that outputs at least three kinds of intensity signals in accordance with intensities of the at least three kinds of light beams that are transmitted through or reflected from a living tissue of a subject; a first signal separator that separates a first signal component and a first noise component based on intensity signals of two kinds of light beams in a first combination selected from the at least three kinds of light beams; a second signal separator that separates a second signal component and a second noise component based on intensity signals of two kinds of light beams in a second combination selected from the at least three kinds of light beams; a first determining section that determines whether a first difference between a first signal absorbance ratio of the first signal component and a first noise absorbance ratio of the first noise component is smaller than a first predetermined value or not; a second determining section that, when it is determined that the first difference is smaller than the first predetermined value, determines whether a second difference between a second signal absorbance ratio of the second signal component and a second noise absorbance ratio of the second noise component is smaller than a second predetermined value or not; and a concentration calculating section that, when it is determined that the first difference is equal to or larger than the first predetermined value, calculates a concentration of a light absorption material in blood of the subject based on a fundamental frequency of the first signal component, and, when it is determined that the second difference is equal to or larger than the second predetermined value, calculates the concentration of the light absorption material in blood based on a fundamental frequency of the second signal component.