Your optometrist determines the type and degree of refractive error you have by performing a refraction test. This can be done with a computerized instrument (automated refraction) or with a mechanical instrument called a phoropter that lets your eye doctor to show you one lens at a time.

Often, an automated refraction test will be performed by a member of the doctor’s staff, and then the eye doctor will refine and verify the results. Your refraction may reveal that you have more than one type of refractive error. For example, your blurred vision may be due to both nearsighted and astigmatism.

Your optometrist will use the results of your refraction test to determine your eyeglasses prescription. A refraction test, however, does not provide sufficient information to write a contact lens prescription, which requires a contact lens fitting.

Eyeglass (spectacle) lenses and contact lenses are fabricated with precise curves to refract light to the necessary degree to compensate for refractive errors and bring light to a sharp focus on the retina.

Vision correction surgeries such as LASIK aim to correct refractive errors by changing the shape of the cornea, so that light rays are bent into a more accurate point of focus.

Please feel free to contact us if you have any questions

Very important: Always make sure you discuss and make decisions about your eye care based upon a formal appointment with your optician or doctor.

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