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Abrasion Testing Of Vacuum Coated Plastic Lenses

The tumble abrasion test [J.D. Masso, SPIE-Proc., Vol.601] has been successfully applied to a variety of uncoated, organosilica coated, and vacuum deposition coated plastic ophthalmic lenses. The vacuum deposited coatings were predominantly antireflection coatings of various spectral types, as well as a few hard coatings. Light scattering measurements were used to quantify the test results. Accelerated lifetime characteristics were obtained by tumbling the lenses for 60 minutes. The results indicate that the thicker a vacuum deposited coating is, the more susceptible it is to abrasion. This observation has been supported by ultramicrohardness measurements which indicate that the brittleness of vacuum deposited coatings increases with thickness.