Inter-laboratory reproducibility of power measurement of toric hydrogel lenses using the focimeter and the Moiré deflectometer

Two separate international ring tests were carried out to assess the measurement capability of the focimeter and the Moiré deflectometer as applied to the power-related parameters of toric soft contact lenses. The results show that in order to measure the sphere and cylinder powers and axis direction using the focimeter a high number of replicate measurements are required to be confident of the test to within reasonable tolerance limits. The availability of the deflectometer provides lens manufacturers with measurement technology which is objective and reproducible and can be used to measure the power-related parameters of toric soft lenses with increased reproducibility using relatively few replicate measurements.