Double cladding structure

Figure 6.8 shows the DMA of a GI POF fabricated by interfacial-gel polymerization and another with double cladding fabricated by coextrusion (see Chapter 5). The attenuation of the GI POF fabricated by coextrusion increases rapidly as the launching position shifts from the core center to the core-cladding boundary, whereas a slight increment in the attenuation is observed in the GI POF fabricated by interfacial-gel polymerization. This is because the structural imperfections at the core-cladding interface that are formed during the coextrusion... 

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