Determining clinical refraction of eye

Abstract

Eye refraction is measured to achieve desired quality via a selected vision characteristics. A characteristic of vision is selected to correlate to the desired quality of vision from a group of vision characteristics comprising acuity, Strehl ratio, contrast sensitivity, night vision, day vision, and depth of focus, dynamic refraction over a period of time during focus accommodation, and dynamic refraction over a period of time during pupil constriction and dilation. Wavefront aberration measurements are used to objectively measure the state of the eye refraction that defines the desired vision characteristic. The measured state of refraction is expressed with a mathematical function enabling correction of the pre-selected vision characteristic to achieve the desired quality of vision. The mathematical expression function may be a Zernike polynomial having both second order and higher order terms or a function determined by spline mathematical calculations. Pre-selected vision characteristics may be determined using ray tracing technology.