An ophthalmic instrument determines the distance between the back surface of an eyeglass lens and the front of the cornea. This measurement is crucial for optimizing the optical performance of corrective lenses, particularly for high-power prescriptions. For example, it ensures the prescribed power is delivered effectively to the eye, minimizing distortion and maximizing visual acuity.
Accurate measurement is essential for achieving optimal vision correction and comfort. Historically, this process relied on manual instruments and calculations, potentially introducing errors. Modern automated instruments offer greater precision and speed, improving patient care and reducing the risk of inaccurate measurements. This advancement has significantly impacted the field of optometry, allowing for more personalized and effective lens fitting.