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We explore and discuss the process of PVA/AA fabrication and the doping of the material with a photosensitive dye creating a photosensitive polymer. The dye used is Erythrosine B (EB), which is sensitive to wavelength of λ = 532nm. We expose the photopolymer with the donor wavelength and initiate the self-writing waveguide (SWW) process and polymerization, creating a single homogenous SWW. We investigate the progress of the SWW as it propagates within the photopolymer and map its change in refractive index relative to its surroundings. When the SWW has been completed we then use a multi-mode Y-Coupler to combine two wavelengths λ = 532nm and λ = 625nm. These two light-waves are injected into the SWW via a Y-Coupler test bed. When the combined light-waves beam exits the photo-sensitive polymer it is directed into another MM fiber. Here it is then measured by an optical analyser that investigates the combined optical wavelengths for interference, coherence, wavelength differential group delay (WDRG), non-linear effects and optical loss. We examine the light-waves for modal interference and birefringence and calculate the combined optical power. The optical insertion testing is now revered and a single wavelength is used. The light-wave enters the MM fiber and then the SWW. It then exists and enters the Y-Coupler. Here the wavelength is captured and the coherence testing is undertaken and the optical properties of the wavelength are analysed and a comparison is carried out to investigate the coherence of the light-wave under test.
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