Lens choices used to be simple – “Do you want single vision, bifocals or trifocals?” Today, with increased demand and available technology, there are literally hundreds of lens designs and thousands of combinations available. Choosing the correct lenses for your needs may seem like an easy decision but when faced with the huge array of possibilities, assistance is often required. Our office prides itself on being able to offer professional advice in this area at no obligation.
LENS DICTIONARY:
Plano
� Non-prescription lens used for fashion, splash/impact protection or sunglasses
� Available in all lens materials
Single Vision
� Single refractive power prescribed for a specific distance
� Available in all lens materials
Bifocal
� Bifocal lenses contain two refractive powers prescribed as a convenient way to see two different distances, most typically near and far, with the same device.
� A bifocal is most commonly indicated by a 28mm wide D-shaped segment located toward the bottom of the eyeglass lens. Other widths and shapes are available.
� Available in all lens materials
Trifocal
� Like bifocals, trifocals typically contain a split, D-shaped segment toward the bottom of the lens. This lens has three prescribed refractive powers and can provide clear vision at near, intermediate and far distances.
� Available in most lens materials
Progressive
� Progressive lenses contain a gradually changing “progression” from the top region of the lens (most commonly the distance power), through a narrow corridor into a region at the bottom of the lens used for close vision. Because of the gradual power change of the progressive corridor, patients are able to see at multiple distances simply by looking through different areas of the lens.
� Available in all lens materials
Occupational
� Occupational lenses are prescribed to fit a specific occupational need, be it strictly related to eye protection or to task specific requirements.
� Primarily used as industrial safety eyewear, these lenses often must comply with ANSI Z87.2 standards for impact resistance.
� Typically these products must be ordered from a specialized wholesale laboratory.
� Available in many lens materials, with polycarbonate being the most impact resistant
� Available in specialty designs such as dual-segment bifocals and trifocals as well as some computer-specific designs
Sports
� Used mostly to provide impact protection from flying objects.
� Eyewear is available that will also help protect the bones surrounding the eye from impact.
� Can be made in most lens designs
� Available only in polycarbonate
Cataract
� Specialized lens prescribed after cataract surgery in which an intraocular implant was not possible. This lens is designed to take the place of the crystalline lens inside the eye and can offer good, but limited vision.
Low Vision
� Lenses for the low vision patient range are designed to offer an improvement in the quality of life of the patient.
� Clear vision is not always attainable, but some improvement in visual function is often possible through use of these lenses
� Available in many lens designs
� Available in most lens materials but best results usually are attained with conventional plastic or glass lenses
� Anti-Reflection is often recommended to allow the greatest transmission of light.
� Low vision lenses can also come in the form of lens-mounted telescopes or specialized hand-held magnifiers
� Patients who feel they may be suffering from low vision should schedule a consultation with our low vision specialist, Dr. Jon Forché
Specialty
� Patients who have very narrowly defined visual needs, such as in the case of a computer user, jeweler, hobbyist or pianist can ask their doctor for a prescription that will help them with their specific task(s) and then consult one of our opticians to determine the best lens design for that prescription.
� Available in all lens materials
� Available in many lens designs
� Can reduce eye strain and increase productivity
