Pulse photometer and method for calculating concentration of light absorber in blood

A pulse photometer comprising:

• a first variation acquirer which is configured to acquire a first variation corresponding to a light attenuation variation of a first light beam due to pulsation of blood in a subject, based on a first intensity signal corresponding to an intensity of the first light beam that is transmitted through or reflected from a body of the subject, and that has a first wavelength;
• a second variation acquirer which is configured to acquire a second variation corresponding to a light attenuation variation of a second light beam due to the pulsation of the blood in the subject, based on a second intensity signal corresponding to an intensity of the second light beam that is transmitted through or reflected from the body of the subject, and that has a second wavelength;
• and
• a concentration calculator which is configured to calculate a blood light absorber concentration, based on the first variation and the second variation,
• the second variation containing a first offset which is based on an inverse of the light attenuation variation of the first light beam.

A method for calculating a blood light absorber concentration, the method comprising:

• causing a pulse photometer to acquire a first variation corresponding to a light attenuation variation of a first light beam due to pulsation of blood in a subject, based on a first intensity signal corresponding to an intensity of the first light beam that is transmitted through or reflected from a body of the subject, and that has a first wavelength;
• causing the pulse photometer to acquire a second variation corresponding to a light attenuation variation of a second light beam due to the pulsation of the blood in the subject, based on a second intensity signal corresponding to an intensity of the second light beam that is transmitted through or reflected from the body of the subject, and that has a second wavelength;
• and
• causing the pulse photometer to calculate the blood light to absorber concentration, based on the first variation and the second variation,
• the second variation containing a first offset which is based on an inverse of the light attenuation variation of the first light beam.