Why is my contact lens prescription a different strength than my glasses prescription?

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Many contact wearers notice that the numbers on their contact lens prescription are different from the numbers on their glasses prescriptions. While some patients may think this is a mistake, there is a very simple explanation: distance.

The distance at which a corrective lens sits from the eye causes a notable difference in the strength of the prescription. This can easily be demonstrated by taking one’s glasses and extending them further away from the surface of the eye. If you have a nearsighted prescription, you will notice the power of the lens becomes weaker as you move it further away, and a farsighted prescription becomes stronger as you move it further away. Because of this, it is important that glasses prescriptions be tested at a similar distance to where a frame sits from a patient’s eye. During an eye exam, your doctor uses a phoropter to present multiple lens options at approximately 12 millimeters from the surface of the eyes.

When fitting contact lenses, the prescription must be adjusted, because contacts are placed directly on the eye, which is 12 millimeters closer than eyeglass lenses.  For nearsighted prescriptions, this means that the minus power of the contact will need to be weaker than in a glasses prescription. For farsighted prescriptions, it means the plus power of the contact will need to be stronger than in a glasses prescription. This difference varies depending on the strength of the prescription and only affects prescriptions over four diopters.

From the eye doctors, opticians and staff at Rinkov Eyecare Centers. We’ve provided comprehensive eye exams, contact lenses, eyeglasses, sunglasses and medical treatment of eye disease such as cataract treatment in Columbus, Ohio, for over 35 years. Come see an optometrist at one of our Columbus locations – Downtown, West, East, Westerville, Dublin, Bexley, Worthington and Nationwide Plaza.

What is astigmatism?

Understanding AstigmatismA lot of our patients ask us what astigmatism is. We find that most think it is a disease or growth in the eye. It is actually just a refractive condition similar to near-sightedness or far-sightedness. It is caused when the cornea or lens of the eye is not perfectly spherical like a baseball, but instead has two curvatures like a football. The curvature is one of the main things to give power to the cornea or lens. Therefore if they have two different curvatures, they have two different powers, and they bend light rays to two different points in the back of the eye. This causes distortion or blur. This can be accommodated for by prescribing glasses or contact lenses with two different curvatures to counteract that of the eye. What to learn more? Check out our website www.rinkoveyecare.com for more information.

From the Eye Doctor, Opticians and Staff of Rinkov Eyecare Centers. Providing quality comprehensive eye exams, contact lenses, glasses, sunglasses and medical treatment of eye disease. Eye exams and eyeglasses in Columbus, Ohio for over 35 years. Come see an Optometrist at one of our Columbus Ohio locations – Downtown, West Columbus, Dublin, Westerville and Reynoldsburg. www.rinkoveyecare.com

CARE : 20|20 : LIFE

*this advice is general in nature and does not constitute an exam. For specific advice, see your eye doctor or healthcare professional.*

Polycarbonate and Trivex Lenses

For many years, most patients have been using glasses lenses made of a material called polycarbonate. The advantage of polycarbonate is that it is thinner, lighter, and most importantly, more impact resistant than regular plastic lenses. The disadvantage of polycarbonate is that the optics of the material are not quite as good.This is especially true in prescriptions that require a lot of astigmatism correction. There is now a newer material available at your optometrist’s office called Trivex. It has all the advantages of polycarbonate, including equal impact resistance, however the optics are much superior to polycarbonate. When Trivex is combined with an anti-reflective coating, patients will notice they have much better vision.

 

From the Optometrists, Opticians and Staff of Rinkov Eyecare Center. Providing quality comprehensive eye exams, contact lenses, glasses, sunglasses and medical treatment of eye disease. Eye Doctors serving Columbus, Ohio for over 30 years. Downtown Columbus, West Columbus, Dublin, Westerville and Reynoldsburg.

www.rinkoveyecare.com

What is Presbyopia?

Presbyopia is a condition in which the lens of the eye becomes hardened.  As this happens the eye slowly loses it’s ability to focus objects from distance to near.   Individuals usually start to notice a difficulty focusing at forty and it usually worsens until the mid sixties when it stabilizes.  It will eventually affect everyone and can easily be monitored and treated with yearly eye exams.  Different treatment options may include glasses, contacts or different types of refractive surgery.

From the Optometrists, Opticians and Staff of Rinkov Eyecare Center. Providing quality comprehensive eye exams, contact lenses, glasses, sunglasses and medical treatment of eye disease. Serving Columbus, Ohio for over 30 years. Downtown Columbus, West Columbus, Dublin, Westerville and Reynoldsburg.

www.rinkoveyecare.com

Downtown – 614-224-2414 West – 614-878-7771

East – 614-861-7771 Westerville – 614-890-3577

Dublin – 614-978-9940

*this advice is general in nature and does not constitute an exam. For specific advice, see your eye doctor

Halos and Starbursts!

Many people have trouble with Christmas lights looking like they have a halo around them or are star bursts. Our patients often notice similar issues with headlights at night. We see this all the time and it is typically due to uncorrected near- sightedness, far-sightedness, or astigmatism. Updating your glasses prescription can help as does a high quality anti-reflective treatment for your lenses. There is also something called higher order aberrations, which requires special equipment to diagnose (we have such equipment available at Rinkov Eyecare Center!).

Near-sightedness, far-sightedness, and astigmatism are lower order aberrations. Lower order aberrations are all that are corrected in typical glasses. Your eye doctor and his/her technicians can also perform tests to determine whether or not you have high order aberrations. If so, there are premium lenses available that do a wonderful job of correcting higher order aberrations (these lenses are especially great for eliminating glare at night).

Want to learn more about high order aberrations? Give your eye doctor a call (or call any of our offices!)

From the Optometrists, Opticians and Staff of Rinkov Eyecare Center. Providing quality comprehensive eye exams, contact lenses, glasses, sunglasses and medical treatment of eye disease. Serving Columbus, Ohio for over 30 years. Downtown Columbus, West Columbus, Dublin, Westerville and Reynoldsburg.

www.rinkoveyecare.com

Downtown – 614-224-2414 West – 614-878-7771

East – 614-861-7771 Westerville – 614-890-3577

Dublin – 614-978-9940

*this advice is general in nature and does not constitute an exam. For specific advice, see your eye doctor.

Attention Parents – You can help your kids feel GREAT about their glasses!

In honor of back to school we have some advise for parents and teachers to help kids feel more comfortable about wearing their glasses.  Sometimes parents and teachers will tell us they need help getting kids to wear their new glasses.  This can be the case, especially for older teenagers who are nervous about standing out, but young children are usually excited to wear glasses.   If kids are use to seeing their parents and teachers look good and want to wear their glasses, the kids are usually excited too.  If they have parents at home with old glasses they feel ugly in and don’t want to wear, the children will probably adopt their preferences.  Glasses have come a long way from the old thick, BCG’s of the past.  People can express their fun, cool personalities now with all the fun styles that are available.  We love to hear how cool a child thinks their new glasses are.  How they love the pink and purple fade with the peace signs.  Glasses can differentiate you and that is very cool no matter your age.  A quiet complement on how good someone looks in their new glasses goes a long way.  The child will be one of many wearing glasses, so don’t worry about them standing out, they won’t.  Try not to make a big fuss about them having to wear the glasses and instead focus on how cool they look in them.  It might even work with the teenagers.

From the Optometrists, Opticians and Staff of Rinkov Eyecare Center. Providing quality comprehensive eye exams, contact lenses, glasses, sunglasses and medical treatment of eye disease.  Serving Columbus, Ohio for over 30 years. Downtown Columbus, West Columbus, Dublin, Westerville and Reynoldsburg.

www.rinkoveyecare.com

*this advice is general in nature and does not constitute an exam. For specific advice, see your eye doctor.