Refraction during an eye examination is a meticulous process essential for accurately assessing and correcting vision problems. It involves several steps:

1. Objective Refraction: This initial assessment uses an autorefractor or retinoscope to measure how light is focused in your eyes without requiring your feedback. It provides a starting point for refining the prescription.

2. Subjective Refraction: This phase involves the optometrist or ophthalmologist using a phoropter and asking you to compare different lens options to determine the sharpest and clearest vision possible. You'll provide feedback on which lenses improve your vision and which do not.

3. Determining Refractive Error: The results of these tests help determine your refractive error, which may include myopia (difficulty seeing distant objects clearly), hyperopia (difficulty seeing close-up objects clearly), astigmatism (blurred vision due to irregular curvature of the cornea or lens), and presbyopia (age-related difficulty focusing up close).

4. Prescription Determination: Based on the findings, a prescription for glasses or contact lenses is generated. This prescription specifies the exact power and type of lenses needed to correct your vision to its optimal level.

Refraction is critical not only for improving visual acuity but also for detecting underlying eye conditions that may affect vision. Regular refraction tests, typically recommended every 1-2 years or as advised by your eye care professional, are crucial for maintaining eye health and ensuring clear, comfortable vision throughout life.