Keratometer with two circular LED arrays: Design, characterization and testing

摘要

The measurement of corneal radius of curvature is of great importance for clinical studies of patients with both healthy eyes and keratometric issues. We present here a simple design for a keratometer formed by two circular LED arrays. Based on basic geometrical ray trace, we obtain the average anterior corneal radius of curvature, the cylinder power for astigmatic correction as well as the axis of astigmatism. Our statistical results denote a 95% of confidence in the measurements obtained with calibrated steel balls, healthy eyes and astigmatic eyes. These results show that this instrument has as good precision as other more complex and expensive keratometers already in the market.