A vision quality metric is an algorithm which interprets the complex wavefront measurements of the aberrations in a human eye in a way which reflects the subjective perception of vision quality. ApplicationsThe vision quality metric is to be used with a wavefront aberrometer to calculate a description of the quality of vision. This metric can serve as the merit function (or optimization parameter) to compute an objective prescription of vision correction. As such, it can be used in an auto-refractor device to provide the defocus and astigmatism descriptors normally used to prescribe spectacles and contact lenses.AdvantagesAn objective refraction, computed from the metric, can have a greater accuracy and reproducibility than a conventional examination done subjectively by an optometrist using a conventional eye chart. It enables the building of a device which could be a more accurate and reproducible alternative to a conventional ?subjective? refraction assessment in which an optometrist examines a patient by trying several lenses to see which seems best. Technology StatusThis technology describes a set of 29 candidate metrics for analyzing wavefront data and the principles for constructing a metric for vision quality. This extends the earlier work at Rochester on the Sharpness Metric (see UR Technology 1-11030-1161).