Uncertainty evaluation method of reflectivity measurement by cavity ring-down spectroscopy

摘要

According to the principle of reflectivity measurement using cavity ring-down spectroscopy, the origin of reflectivity measurement uncertainty was analyzed, we particularly discussed the origin of ring-down time measurement uncertainty, and concluded that the maximum amplitude selection of ring-down curve, the fitting of curve, the time delay of detector, and the dispersity of measurement results were the reasons why. Based on the cavity ring-down spectroscopy method, we built a reflectivity measurement system with the wavelength of 1.319 micron, and obtained the ring-down times of straight and folded cavity respectively. According to the origin of uncertainty, the extensional uncertainty of system was obtained. The result showed the high precision of reflectivity measurement using cavity ring-down spectroscopy.