Surface refractive index of the eye lens determined with an optic fiber sensor.

The use of a fiber-optic sensor for measurement of the refractive index on the surface of eye lenses is described. The technique makes use of the fact that the amount of light reflected at the interface of two media (Fresnel reflectance) depends on the refractive-index difference between them. The sample is probed with a single-mode fiber, and the refractive index is calculated from the proportion of light reflected at the probe-sample interface.