optometry, eye-care specialty concerned with eye examination, determination of visual abilities, diagnosis of eye diseases and conditions, and the prescription of lenses and other corrective measures. In most states optometrists may prescribe drugs for the treatment of eye diseases. The principal concern of early optometrists was the prescription of corrective lenses for defects of vision due to refractive error. Modern optometry also includes the fitting of contact lenses and of telescopic eyeglasses as an aid to the near-blind, as well as the field of orthoptics, i.e., the practice of strengthening the eye muscles and improving their coordination by eye exercises. Prescriptions for corrective lenses provided by an optometrist are often brought to an optician, who grinds and fits the lenses.

The word optometry came into use in 1904 with the organization of the American Optometric Association. Until this time people bought eyeglasses from traveling vendors whose activities were not supervised. With the passage of optometry laws, this method of dispensing glasses was prohibited. Optometrists must now fulfill certain educational requirements and be examined and licensed by the state. Some of the schools of optometry in the United States are affiliated with colleges or universities. Optometry is a specialty requiring a four-year postgraduate professional degree. See also ophthalmology).

Profession concerned with examining the eyes for defects or faults of refraction. Optometrists prescribe optical aids (e.g., eyeglasses, contact lenses), supervise eye exercise programs to treat vision problems, and examine the eyes for disorders such as glaucoma and cataracts. They are generally not licensed to prescribe drugs or trained to perform surgery. Seealso ophthalmology.

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