Eyeglass FAQs

Why do some frames cause a reaction on my skin?
- If metal frames cause a reaction, nickel is the culprit. Most metal frames are made of a nickel alloy. Other metals used include aluminum, stainless steel, titanium, zinc, copper, beryllium, gold and silver. Stainless, titanium, gold and silver are usually hypoallergenic.
  
  Some people can also be allergic to the nose pads on metal frames. Most are made of silicone or acetate, but they can also be made out of polyvinyl chloride (PVC), nickel, titanium or rubber. Silicone is tricky. Certain silicones are hypoallergenic (such as medical silicone), but others can trigger allergic reactions. Both PVC and titanium are usually hypoallergenic. Most plastic eyeglass frames are made of zyl (also called zylonite, acetate and cellulose acetate) or propionate. Other materials used in plastic frames include: polyamide, nylon, polycarbonate, carbon and Optyl (a brand of epoxy resin). Propionate, polyamide, nylon and Optyl frames are all considered hypoallergenic.

I see fine, why do I need to see an Eye Doctor?
- Regular eye exams are the only way to catch "silent" diseases such as diabetes, glaucoma and other conditions in their early stages, when they're more easily managed or treated. Many conditions can be discovered in a carefully planned eye exam. Those who consider mass-produced, over the counter reading glasses are truly doing themselves a disservice, both financially and medically.
  
  One-size-fits-all reading glasses not only do not work well for most people who have a different prescription in each eye, and/or astigmatism, or whose lens and frame parameters are not measured correctly, they bypass the opportunity to have their eyes checked for early detection of many manageable diseases or conditions. For those insisting on selecting glasses not measured specifically for there eyes, headaches and eye fatigue are common symptoms.

How do I know if I need bifocals?
- The most common use of bifocals is for the treatment of presbyopia in individuals aged 40 and over. Whether or not a person has needed vision correction when younger, by the early to mid-forties, the ability to accommodate or focus the eyes has diminished.
  
  Bifocals allow the wearer to see clearly both at distance and near despite the reduced focusing ability. Bifocals may also be used to help align the eyes if a person tends to over-cross his or her eyes at near. If you are over 40 or have any difficulty performing tasks at near, ask us whether bifocals or progressive lenses could be right for you.

How can I stop glare at night or at a computer?
- There can be many causes for this condition. However, many times this problem can be alleviated, or even dismissed, with the use of "AR" (Anti Reflective) Lenses. First and foremost, however, annual or semi annual eye exams are the ONLY avenue to your eye health and the ONLY resource to ascertain the correct reason or cause for any eye ailment!
  
  That being said and once any medical or physical condition is removed as a possibility of cause, then the perfect solution for glare on computer screens, or glare from night driving would be AR (Anti Reflective) Lenses.

What's the secret to getting glasses that look great on me?
- We are fortunate to be staffed with fashion professionals. They not only will assist you in your desire to get the "look" that is most flattering to your features and taste, but they will ensure that your new fashionable eyewear will function nicely with your needs and lifestyle as well. This is easier said than done. That is why we have a very knowledgeable staff dedicated specifically with you in mind.

How often should I get a new pair of glasses?
- This is a personal concern that can address many issues. You should change your eyeglasses when you feel that your existing eyeglasses no longer are supporting your needs, lifestyle, or taste.
  
  In any case a visit to your doctor should not be only considered when you feel it is time for new glasses. You should visit your eye doctor at least once every year, unless otherwise instructed by your eyecare provider.

Are the lenses that change colors OK for sunglasses?
- A popular lens in plastics are called Transitions Lenses. When they're exposed to ultraviolet light, they become darker or change to a different color. However most brands are not as effective in a car or in any vehicle with the "blue or gray Stripe" on a windshield. Because of the ultraviolet blocking nature of the windshields, lenses will remain pretty light when you're driving.
  
  The ultimate sunglass experience can be enjoyed with "Polarized" lenses as these lenses offer the most protection and comfort to the eye so strain and fatigue can become a thing of the past. Transitions is a registered trademark of Transitions Optical, Inc.

What is the difference between Visible Light and Invisible Light?
- Visible light is the part of the sun's energy that you can see.
  It is made up of a spectrum of colors: red, orange, yellow, green, blue, and violet. The eye is not equally sensitive to all of these colors. It is most sensitive to yellows and greens which it can see the best. The eye is less sensitive to reds and blues.
  
  Different Ultraviolet Rays have shorter wavelengths and more energy than visible light rays.
  They can have a harmful effect on the eyes immediately or cumulatively from regular exposure over a number of years. The industry has set standards for how much UV may be transmitted (passed) by types of sunglasses. Ultraviolet (UV) rays are strongest at high altitudes, low latitudes, and in open or reflective environments (like sand, snow, or water). They are also strongest at midday. Scientists divide UV rays into three bands according to wavelength: UVA, UVB, and UVC.
  
  They can have a harmful effect on the eyes immediately or cumulatively from regular exposure over a number of years. The industry has set standards for how much UV may be transmitted (passed) by types of sunglasses. Ultraviolet (UV) rays are strongest at high altitudes, low latitudes, and in open or reflective environments (like sand, snow, or water). They are also strongest at midday. Scientists divide UV rays into three bands according to wavelength: UVA, UVB, and UVC.
  
  UVA-short wave
  UVA rays have been shown to penetrate the under layers of the skin, causing damage and contributing to the skin's aging and cataracts. Therefore, it is certainly wise to require protection from them in sunglasses.
  
  UVB-long wave
  UVB rays, the sunburn rays, are the ones that cause the most concern. They can cause keratitis, which is similar to sunburn on the eye, and also have been linked to the development of cataracts.
  
  UVC
  UVC rays are the shortest, the most energetic, and may be the most harmful. Fortunately, they are blocked in the upper atmosphere and never reach the earth. If sunglasses protect against UVB, we can assume they protect against any possible exposure to UVC.

Why are my lenses so thick?
- Your prescription, your personal measurements, and the size of your frame are the three key factors that will determine final lens thickness.
  
  If you are farsighted your lenses will be thicker at their center, in contrast, if you are nearsighted your lenses will be thicker at their edges. New innovative technology in lens designs, and materials, have allowed us to reduce overall lens thickness by as much as 60% in many cases. Our staff will guide you toward the best possible results in helping you choose the best frame-lens combination for your ocular and fashion needs.

Can the thick lenses be made thinner?
- Absolutely! Newer, thinner lens materials are being developed all the time, and we pride ourselves in constantly being up-to-date with the latest developments and materials in the optical community. This, along with the proper grinding and appropriate frame selection could make your new fashion eyeglasses distinctly thinner. Ask one of our doctors or staff about the newest innovations in lenses today.

Can I use no-line bifocals with fashionably smaller frames?
- Yes. Progressive lenses will allow you to use smaller frames while maintaining terrific vision at all distances. The visual channel that progresses from distance vision to near vision is wider, and more accurate for that 'Tween' vision necessary for clarity in the area too far for close, and to close for far.
  
  It is a wonderful lens for desktop and computer use as well. Please note, that in a few of the small frames, not all frames can be a successful candidate for a progressive lens. With this in mind, our opticians will help you with a proper fit.

Can sunglasses help night vision?
- If your eyes are subjected to intense glare during the day, they will "defend themselves" by trying to adapt. This natural built-in defense mechanism will persist for several hours after the glare is removed, resulting in reduced vision.
  
  Studies show that night vision can be reduced by as much as 50% by this exposure. Wearing sunglasses during the day dramatically improves night vision.

Do regular glasses protect my eyes from the sun?
- Plastic lenses do not protect your eyes. You need to have UV protection from UV rays, which are not inherent in a plastic lens. You can have a UV protective coating applied to a plastic lens, but polycarbonate lenses have built-in UV protection.
  
  Glass lenses protect your eyes from harmful UVB rays but not from UVA. Some professionals think UVA rays might have long-term, damaging effects to your eyes and skin.

What are all those numbers for my prescription?
- An eyeglass prescription is written in a standardized format so it can be understood globally. The right eye, is generally referred to as "OD" or "R", while the left eye is generally referred to as "OS" or "L". The right eye is almost always on top in a written prescription with the left directly below. Ignoring for sample sake, the right or left eye, let's look at a example below:
  
  -2.00 -1.00 x 90. The first number (-2.00) tells us the spherical refractive diopter (a unit of measurement) needed to correct (farsightedness or nearsightedness). In this example, a minus sign in front of the number indicates a correction for nearsightedness. A plus sign would indicate a correction for farsightedness. This is generally true when you are talking about the first set of numbers.
  
  The plus and minus signs on the second number, generally indicates what professional examined your eyes. An optometrist usually refracts in what's referred to as "Minus Cylinder, while an ophthalmologists refracts in "Plus Cylinder". For example, an optometrists script would be -2.00 -1.00 x 90, while the same prescription written by an ophthalmologists would be; -3.00 +1.00 x 180. Please note that the second number has a plus sign, and the last number (180, the Axis) has been transposed 90 degrees.
  
  The second number (-1.00) is for astigmatism. If there is no astigmatism correction needed then you would not see the third (180) number. Sometimes you might see the following; SPH written for a cylinder correction instead of a number and nothing written for the third number. SPH stands for "Sphere" which indicates that there is no astigmatism correction needed.
  
  The final number (180, the Axis line) is the direction of the astigmatism. Astigmatism can be measured in any direction around the clock. We use the numbers from 001 to 180 to indicate the orientation of the correction needed.
  
  Depending on your need, there may be additional numbers in a eyeglasses prescription as well. If your prescription has a set of numbers, or a single number with a symbol such as a triangle, or the letters " BI, BO, BU, or BD that would indicate a prism correction. BI = Base In, BO = Base Out, BU = Base Up, and BD = Base Down. It is not uncommon to have different base directions for either eye.
  
  Also, you will see "ADD" numbers for those requiring bifocals or reading glasses. The ADD number is exactly what it indicates...; an ADD, or an additional script to an otherwise already existing prescription. For example, your prescription is -2.00 for the first number. (In this example there is no astigmatism). For the "ADD " number you have a +3.00.This would indicate that by 'Adding" the +3.00 to the -2.00, your reading prescription would be +1.00 (adding a greater positive number to a lesser negative number results in a positive answer).

What is Ultraviolet (UV) and Infrared (IR) light?
- The light we see with our eyes is really a very small portion of what is called the "Electromagnetic Spectrum." The Electromagnetic Spectrum includes all types of radiation - from the X-rays used at hospitals, to radio waves used for communication, and even the microwaves you cook food with.
  
  Radiation in the Electromagnetic Spectrum is often categorized by wavelength. Short wavelength radiation is of the highest energy and can be very dangerous - Gamma, X-rays and ultraviolet are examples of short wavelength radiation. Longer wavelength radiation is of lower energy and is usually less harmful - examples include radio, microwaves and infrared. A rainbow shows the optical (visible) part of the Electromagnetic Spectrum and infrared (if you could see it) would be located just beyond the red side of the rainbow.
  
  Ultraviolet light (UV) is an invisible light that is part of the sun's radiant spectrum. Exposure to ultraviolet light can cause the lenses of the eye to become cloudy, causing cataracts among many other conditions. Ultraviolet light causes the eye to age faster, thus can also cause macular degeneration. You can't see ultraviolet light. It affects the eye without your awareness to its being there, and the effects are cumulative. Almost everything in nature is affected by UV light, and almost everything deteriorates because of it. Not all sunglass lenses block all of the UV light, but the lens we recommend most is a polarized sunglass lens for sunglasses and polycarbonate lenses for dress wear.
  
  Infrared (IR) is an invisible electromagnetic radiation that has a longer wavelength than visible light and is detected most often by its heating effect. Part of the discomfort you feel in your eyes after being out in the sun for a while is caused by IR light. Not all sunglass lenses block all of the UV light, but the lens we recommend most is a polarized sunglass lens for sunglasses and polycarbonate lenses for dress wear. Although infrared radiation is not visible, humans can sense it - as heat. Put your hand next to a hot oven if you want to experience infrared radiation "first-hand!

Do I need an optometrist and or an ophthalmologist?
- Both are eye doctors that diagnose and treat many of the same eye conditions. The American Optometric Association defines Doctors of Optometry as: primary health care professionals who examine, diagnose, treat and manage diseases and disorders of the visual system, the eye and associated structures as well as diagnose related systemic conditions. They prescribe glasses, contact lenses, low vision rehabilitation, vision therapy and medications as well as perform certain surgical procedures.
  
  The main difference between the two, is that ophthalmologists perform surgery, where an optometrist would not, preferring to concentrate in eye examinations, as well as eyeglass and contact lens related services.
  
  Optometrists would be involved in all of the pre- and post-operative care of these patients; collecting accurate data, educating the patient, and insuring proper healing after the procedure. An ophthalmologist is more of a medical related professional. who would need only to be involved if some kind of surgery were being considered. An optometrist can treat most any eye condition, including the use of topical or oral medications if needed. This might include the treatment of glaucoma, eye infections, allergic eye conditions and others, to name just a few.
  
  A third "O" that often is overlooked, is the optician. An optician is not a doctor, and they cannot examine your eye under their own license. However, a highly trained optician plays an indispensable role in the most successful eye doctors' offices. An optician most often handles the optical, contact lens, and glasses side of things. Based on their vast knowledge of lenses, lens technology and frames, they manufacture eyeglasses, as well as assist in the selection of eyewear, based on the requirements of each individual patient.

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