Study of the tear topography dynamics using a lateral shearing interferometer

The dynamics of the pre-corneal tear film topography are studied on 21 subjects with a purpose-built lateral shearing interferometer. It was found that in most of the recorded data the tear surface is continuous and smooth. Eye movement is identified as a major problem in quantitative tear topography estimation. Based on the reconstructed tear topography maps, the effects of tear dynamics in visual performance, wavefront sensing for refractive surgery and ophthalmic adaptive optics are discussed in terms of wavefront RMS. The potential of lateral shearing interferometry for clinical applications such as dry eye diagnosis and contact lens performance studies is illustrated by the recorded topography features such as post-blink undulation, break-up, eyelid-produced bumps/ridges, bubbles and rough tear surfaces in front of contact lenses.