Proceedings Article | 6 March 2009
KEYWORDS: Reflectivity, Tissues, Integrating spheres, Medicine, Semiconductor lasers, Optical fibers, In vivo imaging, Spectroscopy, Laser applications, Life sciences
Reflection spectra of human Laogong acupoint (PC8) and non-acupoint tissue which irradiated by different power were
studied in the spectral range from 400 nm to 1000 nm in vivo. A wavelength of 808 nm semiconductor laser was used for
irradiation at the power of 0 mw (empty irradiation), 20 mw, 50 mw and 100 mw for ten minutes. Reflection spectra
were measured with an AvaSpec-2048 optical fiber spectroscopy with an integrating sphere attachment. The result shows
that when empty irradiated, the shape of the reflectance spectra of Laogong acupoint and non-acupoint are similar, they
have the same troughs at 423 nm, 544 nm, 577 nm and 980 nm, the reflectance at these wavelengths for Laogong
acupoint are 17.1%, 26.1%, 25.9%, 35.0%, and for non-acupoint are 17.1%, 27.6%, 28.1%, 36.5%. But from 475 nm to
1000 nm, the reflectance of Laogong acupoint is smaller than that of non-acoupoint. After irradiated by laser at the
power of 20 mw, 50 mw, and 100 mw, there is a very significant decrease in the reflectance spectra of Laogong acupoint
comparing to that of empty irradiated, and the higher power, the lower reflectance. But there is just a small decrease in
the reflectance spectra of non-acupoint comparing to that of empty irradiated. From the above results, it is clearly to see
that Laogong acupoint is more sensitive than non-acupoint when irradiated by semiconductor laser.
