The most important factors are:. Still, contact lens and glasses prescriptions are similar in that they both require routine eye exams in order to be most effective. Eye exams are the best way to monitor vision problems, and they also ensure your prescription is up-to-date and that you continue to see clearly as your eyes change.
Eye care professionals recommend getting annual updates to both your glasses and contacts prescriptions in order to keep your vision sharp. If you have children, make sure they never have to squint at the board during class by scheduling eye exams in August or September. For yourself, the new year is a great time to touch base with your optometrist and get fitted for a fashionable new pair of glasses or a fresh pair of contacts. In , VisionWatch reported that million people all over the United States used some form of vision correction, and about 11 percent alternated between glasses and contacts.
Ready for your yearly eye exam? A minus - sign indicates you are nearsighted. The further from zero the number is on your prescription, the stronger your prescription is.
Power is the same as sphere SPH. BC is the abbreviation for base curve, the measurement of the curvature of the back surface of the contact lens. DIA stands for diameter, and indicates the size of your lends. It works with the base curve to determine how your lens will fit. Your eye care professional will know which one is best for you. What Causes Headaches Behind the Eyes? Are Carrots Good for Your Eyes? Open- vs. What to Know About a Scotoma.
Yours may differ but should contain the same information. Note: not everything shown on the above table will necessarily be included on your prescription.
The above is just an example of what could be found on your prescription and what will not be found on your prescription depending on whether you wear contact lenses or glasses. Contact lenses prescriptions include certain specifications that are not part of a glasses prescription, these include: Base curve : the base curve measures the curvature of the lens; it is determined by the actual shape of your eye and produces the right lens fitting.
Diameter : the lens diameter specifies the overall size of the lens. Along with the base curve, this determines how the lens fits on the eye. Lens material : in days gone by, glasses were made from actual glass, nowadays, most glasses are made of a lightweight plastic. Contact lenses on the other hand, are made from a range of hydrogels. These are split into hydrogel or silicone hydrogel contacts. Those with sensitive or dry eyes generally do better with silicone hydrogel contact lenses as they allow a greater level of oxygen and hydration into the eye.
A glasses prescription contains a sphere indicating the lens power, a cylinder indicating strength of any astigmatism if there is one stated and an axis showing the orientation of the cylinder.
A contact lens prescription may also include an axis and cylinder if it is a toric lens for astigmatism, or an add if it is a multifocal lens, these are the only two measurements that can be found on both contact lenses and glasses prescriptions.
This indicates the extra power you need for astigmatism correction. A higher number denotes a more severe level of astigmatism. The cylinder value for a glasses prescription on the other hand can be a plus or minus. No — you cannot directly convert a glasses prescription to a contact lens prescription. Equally, you cannot convert a contact lens prescription to a glasses prescription.
The simple answer to this question is no — you cannot and should not use your glasses prescription to try to calculate your contact lens prescription.
It should also be noted that not everyone who needs glasses can also wear contact lenses, it is important that you are examined separately. Some people have sensitive corneas or other eye related complications and will simply never be able to adapt to wearing lenses. You can order contact lenses online , but you must have a valid prescription from an optician.
Once you have your prescription, you may order you lenses anywhere you like and it is cheaper to order your contact lenses online. You can order your glasses online from Feel Good Contacts simply by choosing your lens type and then entering your prescription.
If you have already placed an order with us before, you will not need to enter your prescription again unless it has expired.
It is illegal for your optician to withhold your contact lens or glasses prescription from you.
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