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Auto Refractor/Keratometer

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An autorefractor is a machine used to quickly measure a person's refractive error and prescription for eyeglasses or contact lenses. This is achieved by measuring how light is changed as it bounces off the back of a person's eye. The automated refraction technique is quick, simple and painless. The patient takes a seat and places their chin on a rest. Using one eye, they look into the machine at a picture of a balloon. The picture moves in and out of focus as the machine takes readings to determine when the image is on the retina. Several readings are taken which the machine averages to form a prescription. No feedback is required from the patient during this process. 

 
The keratometer is used to determine the shape of the cornea. It does this by looking at the reflection of light off of the cornea at sixteen different points. These measurements are used to diagnose conditions such as astigmatism , Keratoconus, corneal scarring and corneal distortion. A keratometer is commonly used to fit contact lenses as well.
 
The accuracy of this combined instrument allows us to have a viable starting point in determining your spectacle and contact lens prescription.