| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily analyze the blood flow state on a skin surface such as gingiva by detecting the reflected light in which a light emitted from a laser beam source is reflected near the surface of a living being, converting it into electric signal, and computing and displaying the cross correlation between the time change of a plurality of frequency components of this signal and the heartbeat of a subject. SOLUTION: When the output light 2 from a laser beam source 3 is emitted toward the gingiva surface 1 of a subject, the output light 2 is reflected as a scattered light 4. This scattered light 4 is received by a photoelectric converting element 5 and converted into electric signal, and this signal is transmitted to the arithmetic part 14 of a processing means 11 through an amplifier 5, a band pass filter 7, and an A/D converter 8. The heartbeat signal of the subject is detected by a heartbeat signal detecting part 9, and transmitted to the arithmetic part 14. In the arithmetic part 14, time-frequency analysis is performed for an optional frequency component of f1 , f2 ,... to compute the intensity time fluctuation, and the cross correlation coefficient with the heartbeat signal is also computed for the optional frequency accompanied by time fluctuation, and displayed on a display means 12.</p> |
