Laser Induced Refractive Index Change (LIRIC) uses femtosecond laser pulses to locally modify a material’s refractive index below material damage thresholds. This technique has been successfully applied to create refractive correctors in wet ophthalmic materials such as hydrated contact lenses. However, applying LIRIC in wet contact lens materials to mass produce refractive correctors would require drastic changes to the current manufacturing infrastructure. To integrate LIRIC in the production line in a cost-effective manner, applying this technique in a dry contact lens is necessary. Therefore, this study seeks to understand how the absence of water affects LIRIC writing mechanisms. Our experiments have shown that LIRIC writing using 400nm laser light produced rough, non-uniform regions of index change in dehydrated Hydroxyethyl Methyl Acrylate based hydrogels. However, in dehydrated silicone hydrogels, LIRIC successfully induced greater index changes than when the materials are in hydrated state.
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