A tool used by eye care professionals helps determine the appropriate contact lens power based on the refractive error of the eye and the distance between the back surface of the contact lens and the front surface of the cornea. This distance is known as the vertex distance. For example, a patient with a high prescription might require a different contact lens power than what their glasses prescription indicates due to this distance. The tool accounts for this difference, ensuring the patient receives optimal vision correction.
Accurate vision correction with contact lenses relies on precise power calculations. This process becomes particularly critical for individuals with moderate to high refractive errors, where small discrepancies in lens power can significantly impact visual acuity. Historically, accounting for vertex distance required manual calculations. Modern digital tools simplify and streamline this process, improving accuracy and efficiency in contact lens fitting. This ensures patients receive the most appropriate prescription, minimizing the risk of visual distortions and discomfort.