Cargille Optical Gel, Code 0608, 1 oz.:
Optical coupling aid for optical fibers and optical components:
The gels reduce or eliminate internal reflectance thereby increasing the transmittance of light. This is accomplished by having a refractive index and dispersion that is similar to many glasses and optical plastics, and closely matches the refractive index and dispersion of fused silica.
Mode stripping gel:
When one of the gels is coated onto a silica fiber that has cladding, it will remove the signal from the cladding. This is useful when evaluating fiber systems using only short fiber lengths, in that the signal that is carried for a short distance in the cladding can be eliminated from the system and detectors will record only the signal propagated by the fiber core. This is quicker and easier than mechanically stripping away the cladding and is non-destructive.
Optical gels are available in two refractive indices. n=d 1.46 and 1.52
Comparing the different products:
Optical Gel Codes 0607 and 0608 are optically and chemically nearly identical, and both are used for coupling optical fibers and other optical components, and for mode stripping. Optical Gel Code 0607 is a thinner gel than 0608 and, upon standing, the surface of 0607 is a thinner gel than 0608 and the surface of 0607 will normally appear to be fluid. Code 0608 appears to be much less fluid.
Optical Gel Code 0607, although not water soluble, is made to "disperse" when immersed in water to facilitate cleaning.
Optical Gel Code 0608 was specially made not to "disperse" in water, for applications where water immersion without dispersing or changing is required.