Prescription Glasses

An eyeglass prescription is an order written by an eyewear prescriber, such as an optometrist or ophthalmologist, that specifies the value of all parameters the prescriber has deemed necessary to construct and/or dispense corrective lenses appropriate for a patient.

If an examination indicates that corrective lenses are appropriate, the prescriber generally provides the patient with an eyewear prescription at the conclusion of the exam. In the United States, the FTC (Federal Trade Commission) requires eyewear prescribers to give each patient a copy of their prescription, immediately following an exam, even if the patient doesn't ask for a copy.

The parameters specified on spectacle prescriptions vary, but typically include the power to which each lens should be made in order to correct blurred vision due to refractive errors, including myopia, hyperopia, astigmatism, and presbyopia. It is typically determined using a phoropter and asking the patient which of two lenses is better, or by computer automated refractor, or through the technique of retinoscopy. A dispensing optician will take a prescription written by an optometrist or ophthalmologist and order and/or assemble the frames and lenses to then be dispensed and sold to the patient.