| 摘要 |
<p>A method and apparatus is disclosed to determine a concentration of dopant in soot that constitutes at least a portion of a soot preform (12) used to form an optical wave guide. The photon source (30) irradiates the soot preform on a mandrel (14). X-ray fluorescent emissions, from the irradiated soot are detected, and the concentration of dopant is determined based on the detected X-ray fluorescent emissions. Additionally, the concentration of dopant in layers of soot on the preform can be controlled by utilizing the detected X-ray fluorescent emissions to determine a deviation between a concentration of dopant in the soot and a predetermined concentration, and adjusting deposition conditions based on the deviation.</p> |
