Abstract: A method and associated system improve accuracy in objective refraction measurements by including the measured distance between the photoreceptors of a subject's eye and the scattering location of light during the objective refraction measurements. Chromatic aberrations in the objective measurements are also compensated. The distance between the photoreceptors and the scattering location may be determined by adjusting a distance between a rotating speckled light pattern and an eye until the speckled light pattern appears to be stationary, or by employing a Scheiner disk.

Abstract: A system for mapping a three-dimensional structure includes a projecting optical system adapted to project light onto an object, a correction system adapted to compensate the light for at least one aberration in the object, an imaging system adapted to collect light scattered by the object and a wavefront sensor adapted to receive the light collected by the imaging system and to sense a wavefront of the received light. For highly aberrated structures, a number of wavefront measurements are made which are valid over different portions of the structure, and the valid wavefront data is stitched together to yield a characterization of the total structure.

Abstract: A system and method of measuring the curvature of a surface of a object operate by illuminating the object surface with a light pattern having a known size to produce a virtual reflected image from the object surface; measuring a size of the virtual reflected image produced by the object surface from the light pattern; and calculating a curvature of the object surface from the known size of the light pattern and the size of the virtual reflected image.