PRODUCTION OF AIR CLAD OPTICAL FIBER

摘要

PROBLEM TO BE SOLVED: To produce an air clad optical fiber having a large light accepting angle which can transmit a larger quantity of light without decreasing the optical transmission efficiency due to scratches on the core material. SOLUTION: By this method, an air clad optical fiber consisting of a core material 1, a protective tube 2 covering the outer face of the core material 1, and an air layer 3 between the core material 1 and the protective tube 2 is produced. By expanding the protective tube 2 around the core material 1, the air layer 3 is formed between the core material 1 and the protective tube 2. This method avoids such a problem that the protective tube 2 and the core material 1 rub each other to give flaws to the outer face of the core material 1 in the production of an air clad optical fiber by inserting the core material 1 into the protective tube 2.