PROBLEM TO BE SOLVED: To correctly determine a state of a circulatory system of a subject.SOLUTION: A first sensor 10 emits light to a first region of a subject, pressurizes the first region, and measures reflection light or transmitted light from the first region. A second sensor 11 emits light to a second region of a subject, pressurizes the second region, and measures reflection light or transmitted light from the second region. A first measurement value calculation section 212 calculates an index related to a blood oxygen saturation or a blood re-injection time on the basis of a change of an amount of light reception to be measured by the first sensor 10 (calculates a first measurement value). A second measurement value calculation section 213 calculates a blood oxygen saturation or a blood re-injection time on the basis of a change of light reception to be measured by the second sensor 11 (calculates a second measurement value). An evaluation section 214 evaluates a circulatory system of a subject on the basis of comparison processing using the first measurement value and the second measurement value.SELECTED DRAWING: Figure 4
