摘要 |
A light beam is directed through the deposited layer in an optical fiber preform during sintering of the deposited material. The degree of transmission of the light indicates the degree of sintering of the deposit that has occurred due to the moving hot zone. The speed of traversal of the hot zone can thereby be maximized. This technique is especially desirable for use with the tandem hot zone process utilizing a plasma fireball for high-speed preform manufacture. |