Contact lens and methods of manufacture and fitting such lenses and computer program product

摘要

The invention is directed to a contact lens design and methods of manufacturing, fitting and using such lenses. The contact lens may be designed for use in a corneal refractive therapy (CRT) program. The lens provides a design which allows proper fitting of a patient, whether for corrective contact lenses or for a CRT program. Due to the rational design of the lenses according to the present invention, a minimal number of lens parameter increments can be identified to cover the range of common corneas. It is therefore possible to provide pre-formed lens buttons or blanks which are easily formed into a final design, thereby simplifying and speeding up the treatment process. Further, any adjustment of the lens design which may be required based upon trial fitting or the like, is easily envisioned and implemented by the fitter.

主权项

1. A computer program product for designing a contact lens comprising:
a computer usable storage medium, a computer readable program code, responsive to user inputs, for modeling a contact lens to have a central zone having a posterior surface curvature selected according to characteristics of a patient's cornea, and a first and at least one second annular zone wherein the at least one second annular zone is positioned and shaped to engage said cornea upon alteration of its shape a predetermined amount, and the first annular zone formed as a sigmoidal curve connecting the central zone and the at least one second annular zone, and computer readable program code for calculating cutting parameters for a lathe used to produce said lens from a blank of material.