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Generally speaking, one should have their eyes examined once every two years, unless there is a health issue such as glaucoma, cataracts or retinal problems. In such cases, eye exams are more frequent. It is advisable that children have a complete eye exam prior to entering school.

The three O’s in optical consist of consist of Ophthalmologist, Optometrist and Optician.

An Ophthalmologist is a medical doctor, whose primary function is to treat eye disease, perform eye surgery and prescribe drugs.

An Optometrist is a Doctor of Optometry, whose primary function is to examine the eyes in order to determine the correct prescription for either glasses or contact lenses. The Optometrist can diagnose health issues, prescribe drugs related to eye health and fit contact lenses.

An Optician is similar to a pharmacist. The Optician fills the doctor’s prescription by fitting the patient with either eye glasses or contact lenses.

Standard sunglasses provide average protection from bright sunlight by absorbing approximately 80% of visible light and 100% of harmful ultraviolet light. A polarized sunglass is superior to a standard sunglass in that it filters out both visible and ultraviolet light, but also filters out reflected glare. Reflected glare is the glare that one experiences when driving into the rising sun or setting sun. Reflected glare is also obvious on the surface of water. Both standard sunglass lenses and polarized sunglass lenses are available in prescription and non-prescription form.

Cataracts are opacities, which develop within the natural crystalline lens of the eye. The natural crystalline lens is positioned behind the pupil. As the opacities develop and progress, they inhibit the amount of light passing through the eye and striking the retina. The less light striking the retina, the poorer the vision. As cataracts develop, vision becomes less clear. Glare at night also becomes more pronounced.

Cataract surgery greatly improves vision, but it does not necessarily eliminate the need for glasses. Directly after surgery, most patients experience excellent vision; however, as the eye heals, changes may occur, which require visual correction through eyeglasses. Age and health related issues, such as diabetes, may also contribute to the need for prescription eyeglasses in the post-cataract patient.

Anti-reflective coating is a lens treatment, which increases light transmission through an eyeglass lens. It reduces reflections and improves clarity of vision. Anti-reflective coatings may be single-layer coatings or multi-layer coatings. Single-layer coatings are adequate, but multi-layer AR coatings tend to be more clear, more durable, more scratch resistant, more hydrophobic (easier to clean) and longer lasting.

Computer lenses are occupational lenses specifically designed for optimum vision at the intermediate or computer distance. This is accomplished by the doctor prescribing either a single vision lens, which focuses at that precise distance or a variable focus occupational lens.

A computer coating is a multi-layer lens coating, which filters out blue light and reduces glare. Blue light, which scatters on the retina, is emitted from computer screens and digital devices. Blue light scatter causes blurred vision, dry and irritated eyes, headaches and difficulty refocusing. Digital eye strain is the number one computer-related complaint in the United States, ahead of carpal-tunnel syndrome. Computer coatings offer the user more comfort, clarity of vision and reduced eye strain and fatigue.

Fortunately or unfortunately, there is no “one size fits all” progressive lens. At this writing, there are literally hundreds of different progressive lenses available to the consumer. Each manufacturer has a different lens design, corridor length and technology within the lens, which ultimately determines how well you will see out of that particular progressive and how comfortable you will be with your vision. Some progressives have narrow reading areas; some are wider. Some progressives have a lot of peripheral power changes, which result in a “fish-bowl” or “swimming” sensation. The newer digital progressives provide wider visual fields, infinitely better visual clarity and virtually little or no peripheral power changes. Your eyecare professional should be equipped to discuss the differences in design and relative costs to best serve your individual needs.

In the state of New York, prescription (Rx) eyeglasses are required to be measured and fitted in person by a licensed Optician or Optometrist. Rx eyeglasses are highly customized and at their very core, a medical appliance. Proper fabrication of a pair of Rx eyeglasses include:

• Correct fitting of the frame to the face (i.e. bridge size, lens size and temple length).
• Adaptation of the Rx for proper lens design (i.e. single vision versus multifocal lenses, lens materials, lens thicknesses, lens treatments and/or coatings, occupational use lenses, sun or sports protection, and more).
• Accurate grinding of the Rx including spherical and astigmatic correction and axis direction.
• Precise measurements and placement of optical centers and usable optical quadrants.
• Meeting federal safety standards for impact resistance as put forth by the American National Standards Institute (ANSI).
• Adjustment of glasses for proper visual acuity (i.e. proper pantoscopic or retroscopic tilt, parobolic face form, vertex distance and planar alignment).

When purchasing eyewear over the internet, how does one know:

• If the frames fit properly? Do they slip or hurt?
• Are the lenses ground properly? Do they cause eye strain, poor vision or headaches?
• Do the lenses meet the federal safety standard for impact resistance?
• Are the lenses susceptible to shattering, especially if they are produced in a foreign country?
• Who is going to service them?

All of the above daily duties and responsibilities are done by your eyecare professional when they produce a pair of glasses. It is our mission to protect and best serve the health and safety of your visual needs. All eyecare wearing consumers are advised to make wise and well informed decisions.