| 摘要 |
PROBLEM TO BE SOLVED: To provide a pulse photometer capable of improving accuracy in calculation of concentration of photoabsorption substance in blood.SOLUTION: A pulse photometer emits 3 kinds of light having different wavelengths and receives 3 kinds of light permeating through or reflected on subject's living body 20. A first signal separation part 13 separates first signal component S1 and first noise component N1 based on intensity signals I1, I3. A second signal separation part 14 separates second signal component S2 and second noise component N2 based on intensity signals I2, I3. It is determined first difference between absorbance spectrum ratio of the first signal component S1 and absorbance spectrum ratio of the first noise component N1 and second difference between absorbance spectrum ratio of the second signal component S2 and absorbance spectrum ratio of the second noise component N2. SpO2 calculation part 18 calculates SpO2 of the subject based on base frequency of the first signal component S1 when the first difference is determined as a first predetermined value or more, and calculates SpO2 based on base frequency of the second signal component S2 when the second difference is determined as a second predetermined value or more. |
