| 摘要 |
PURPOSE:To prepare image fiber permitting easy preparation of satisfactory perform by packing quartz optical fiber in a quartz cylindrical vessel deposited with porous quartz material, and discharging gas being present in a space part in the cylinder by heating. CONSTITUTION:Optical fibers providing a picture element are packed in a quartz cylindrical vessel 2 having a porous quartz material 5 to the outside or inside thereof, and the cylindrical vessel 2 is heated by an external heating source 6 and the gas contained in the space part of the cylindrical vessel 2 is exhausted. During the while, the diameter of the cylindrical vessel 2 is reduced to eliminate the space part and an image fiber is prepared thereafter. By this process, the reduction of the diameter can be executed quite slowly, therefore uniformly. As the result, a preform of superior image fiber having small deforma tion of the sectional shape is obtd. |
