Since the beginning of the 1970s the scale of productio […]
Since the beginning of the 1970s the scale of production of optical fiber since the optical fiber preform manufacturing technology research and improvement has never been interrupted. AT & T (Lucent) invented the improved chemical vapor deposition (MCVD, Modified Chemical Vapor Deposition) process, the United States Corning subsequently developed for large-scale production of fiber tube outside the vapor deposition method (OVD, Outside Vapor Deposition ) Process, followed by OVD process has been improved, has issued a seventh generation of technology, so that production efficiency and production costs significantly reduced; and Japan NT & T on the basis of OVD to improve the introduction of the vapor phase axial deposition method VAD, Vapor Axial Deposition); Alcatel of France developed high-frequency plasma technology to produce advanced plasma vapor deposition (APVD) preform production technology; the Netherlands Philips has developed a plasma chemistry (PCVD , Plasma Chemical Vapor Deposition) Successfully applied in the production.
Early optical fiber preform manufacturing technology using one-step method, in early 1980 began to use the casing method of preparation of optical fiber preforms, so that the optical fiber preform manufacturing process to achieve a one-step to two-step method of change, that is, the first preform rods, In the mandrel outside the use of different technologies to create outer cladding, increase the number of single preforms can be drawn to increase the number of kilometers to improve production efficiency. It is generally believed that the manufacture of mandrel determines the transmission performance of the fiber, while the outer layer determines the manufacturing cost of the fiber. OVD and VAD belong to the outer deposition process. In the outer cladding process, the external deposition technique refers to OVD and VAD. The external spray technology mainly refers to the use of plasma sprayed quartz sand. In the process of manufacturing the mandrel, MCVD and PCVD are called tube deposition process. Process. Today's optical fiber outer cladding manufacturing techniques include casing method, plasma spraying method (Alcoa) manufactured by Alcatel Corporation, flame hydrolysis method (SOOT), and sol-gel method (Sol-gel method) ), Which SOOT method is generally refers to OVD and VAD flame hydrolysis outside the deposition process.
MCVD method is the use of external deposition technology to replace the casing method of making large preforms, the formation of MCVD external deposition process combined with the process, thus changing the traditional MCVD process deposition rate is low, the accuracy of poor geometric accuracy, reducing production costs, The quality of the preform. Since then, some companies have developed low-cost large-size casing process, casing preparation process for the Sol-gel and OVD method.
Preform preparation process OVD method has been developed from a single torch deposition to a multi-burner for the past two decades. The deposition rate has increased exponentially and a device has been deposited with multiple rods at the same time and a preform The first step to the development of two-step method, that is, the first preparation of large diameter mandrel, and then pull into a small diameter mandrel or not thinning, and then use the outer layer technology to prepare fiber preform, improve production efficiency, Cost of production. In addition, the MCVD method, especially the PCVD method, the OVD and VAD methods, makes it easier to precisely control the radial refractive index distribution of the mandrel, thus making it more effective for preparing multimode fiber MMF and non-zero dispersion fiber DZDF core preforms.
Over the past 20 years, fiber optic preform technology has been a lot of development, the United States CORNING company first use SOOT outsourcing technology instead of casing applied to industrial production. In 1990, Alcatel Alcatel plasma spraying technology and the United States Lucent developed Sol-gel outsourcing technology to replace the casing technology, and thus the use of casing preparation of optical fiber prefabricated VAD manufacturing fiber core rod manufacturers are using SOOT outsourcing technology.log on to our official website for more details :http://www.fuucable.com/