Cladding glass

Fig. 6. Double crucible configuration showing core glass (upper crucible) flowing through molten cladding glass in lower crucible to yield graded-index...

Blanks can also be made using Vapor Axial Deposition (VAD) (Fig. 21). The process involves simultaneous flame deposition of both core- and cladding-glass soots onto the end (ie, axially) of a rotating fused-siUca target rod. The finished perform is then consoHdated in a process similar to the OVD process. 

The angle a in practice is of the order of few degrees and consequently the SH wave will be guided in the cladding glass. 

Cladding glass with a lower refractive index... 

Step-index fibers are manufactured using the rod/tube or the double crucible process, in which the core and cladding glasses are melted separately from ultrapure powders and transferred into two crucibles with concentric orifices at the bottom and drawn into a fiber. To obtain a semi graded refractive index profile, a diffusion process can be applied in a curing furnace. Step index fibers with a transmission loss of < 10 dB/km at a wavelength of 0.8. pm can be obtained. 

To prepare 3-g batches, a solution of 3.42 g silver nitrate (slight excess) in 100 ml water is placed in a 500-ml beaker and heated to 60-70°C. The solution is stirred with a rubber-clad glass rod, and a solution of 1.3 g sodium azide in 100 ml water (60-70 C) is added within 3-4 min. The precipitate is stirred until well coagulated and then transferred to a Buchner funnel. To avoid contact with the hard funnel material, both the bottom and walls are covered with filter... 

AgClad, Silver-clad glass filaments and platelets, PQ Corp. 

E. Simiu and E. M. Hendrickson, Wind Tunnel Data and Equivalent 1-Minute Loads for the Design of Cladding Glass, Proceedings. Seventh International Conference on Wind Engineering. Aachen, West Germany, July 1987. 

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