3^ Base In / 12^ Base Out Vergence Facility prism flipper
Our prism flippers are clearly marked with the power and base orientation. All prism lenses are chemically hardened glass (plano base curve). The frame has an indicator on each side to show prismatic power and position.
Night myopia is often difficult to assess in routine refraction. The myopic shift under scotopic conditions is often bothersome to many of our patients. Since the extent of the shift is variable from one person to another we have put together flippers to establish an over correction for each individual.
Loan patients a set of flippers to determine if more minus is needed while driving or star gazing before making a second pair of glasses for use at night.
Flipper lenses: either -0.25/-0.50 or -0.75/-1.00