PRODUCTION OF OPTICAL FIBER PREFORM

摘要

PURPOSE:To provide the title matrix with accurate reproducibility. CONSTITUTION:Parallel beams 10 transmitted through the flame 6 of a burner 2 are passed through the first and second gratings 12, 13 and projected onto a screen 17. The shift level of moire fringes developed on the screen 17 is catched with a CCD camera 18, analyzed using a computer 19, thereby detecting the change in the temperature and/or density within the flame 6. With the resulting signals, the feed of a gas to the burner 2 is controlled.