Contact lenses and glasses share one common goal: helping you see the world more clearly. Both options are popular and well-loved for many reasons.
The decision between contact lenses and glasses all boils down to your personal preference. Many people enjoy the benefits of both!
Contacts are helpful for active, busy people on the go who prefer the natural look of contacts and a frame-free face. However, they require more maintenance and care than glasses.
Glasses are more customizable, making them a staple accessory for more stylish and fashion-forward days. Their fuss-free and durable quality makes them a valuable investment you can enjoy for years.
You can’t go wrong with either option. What matters most is having an accurate, up-to-date, and comfortable vision prescription.
Do Contact Lenses & Glasses Share a Prescription?
Contact lenses and glasses don’t share the exact same prescription.
Glasses rest on the bridge of your nose, a few millimetres away from your eyes. In contrast, contact lenses rest directly on the eye’s surface.
The difference in distance and placement affects how light enters the eye and is reflected in the lens. Additionally, contacts require measuring the shape and size of your eye for an accurate and comfortable fit.
It may seem harmless, but the differences are crucial for supporting your comfort and correcting blurry vision. The prescription strength might not align correctly with your eyes’ needs without adjusting for lens distance, leaving you squinting instead of seeing clearly.
Your optometrist will provide 2 distinct prescriptions: one for glasses and another for contact lenses. Keep in mind that a contact lens prescription requires a separate appointment—a contact lens exam—to determine the fit and prescription.
Breaking Down a Vision Prescription
During your eye exam, the refraction test is how your optometrist determines your vision prescription. These numbers are what opticians and lens manufacturers use to craft lenses tailored to your eyes.
If you’ve ever glanced at your prescription and felt confused by all the letters and numbers, don’t worry—you’re not the only one! Each of those values has a distinct purpose.
A typical vision prescription includes the following measurements for glasses and contact lenses.
Sphere (SPH)
Sphere (SPH) is the number that measures the lens power required to correct hyperopia (farsightedness) or myopia (nearsightedness) and is measured in diopters (D).
Every vision prescription will include a sphere value, even at 0.00 D. A negative sign (-) signifies myopia. A positive (+) sign indicates hyperopia.
Cylinder (CYL)
Cylinder (CYL) provides the lens power needed to correct astigmatism. It’s usually negative. If there’s no astigmatism, this column remains blank.
Axis
The axis measurement identifies where astigmatism should be corrected on the lens. It’s measured in degrees from 1 to 180.
Addition (ADD)
When you get multifocal lenses, such as bifocals, you’ll likely see “ADD” on your prescription. The “addition” number tells opticians the extra magnifying power needed in your lenses to help you see clearly up close for activities like reading.
You might also see a value in the ADD section if you need specialized lenses, like prism lenses, to help correct any slight misalignment between your eyes.
OD & OS
OD and OS are Latin abbreviations for each eye. OD refers to your right eye, OD is the left, and OU refers to both eyes.
Contact Lenses Only
A contact lens prescription includes additional measurements relating to the shape and size of your eye for a comfortable and accurate fit:
- The base curve (BC) describes the curvature of the contact lens’s inner surface, measured in millimetres (usually between 8–10 mm)
- The diameter (DIA) measures the width of the contact lens in millimetres (ranging from 13–15 mm)
Pros & Cons of Contact Lenses
Since contact lenses sit directly on the eye, they can offer a broader, more natural field of vision that eyeglass frames can obstruct. When fitted comfortably, your lenses won’t fall out during workouts, sports, or long days, making them a convenient option for people on the go.
Contact lenses help you confidently show your natural face without frames blocking your features.
There are various lens types available, making it easy to accommodate people with severe dry eyes or more complex conditions like keratoconus.
However, some of the drawbacks of contact lenses include:
- Daily cleaning & maintenance to reduce the risk of infection, irritation, & discomfort
- Annual contact lens exams & fittings to verify the health of your eyes & support safe contact lens wear
- Dryness & irritation if worn too long, including a risk of developing chronic dry eye
Pros & Cons of Glasses
Glasses are a tried and true staple for many reasons. They are low-maintenance, customizable, and conveniently stylish for the fashion-forward.
When you take good care of your glasses, you can invest in a high-quality pair that should last years.
Keep up with your routine eye exams to maintain your eye health. Unlike yearly contact lens prescriptions, glasses prescriptions are valid for 2 years.
For many people who don’t like the idea of touching their eyes, glasses are the preferred choice. Plus, glasses don’t require daily cleaning or disinfection, making them ideal for anyone who prefers a fuss-free routine.
Prescription lenses technology is always evolving. Many glasses offer optional lens treatments or coatings like UV protection, blue light filters, or anti-reflective coatings, seamlessly supporting various lifestyles.
Glasses can offer reliability and low maintenance, but they have a few drawbacks:
- Eyeglasses lenses are prone to fogging in colder weather or when wearing face masks
- The frames can be restrictive during high-impact physical activities, like running or playing sports
- A poor fit or extended daily wear can cause discomfort or headaches if the frames press against your nose or ears
Update Your Vision in Style
When it comes to choosing between glasses or contacts, it all depends on how each option aligns with your comfort level and day-to-day life.
Wearing an up-to-date vision prescription matters more. If it’s been a while since your last eye exam, or you’d like to explore your lens options with your optometrist, our team is happy to help.
Connect with us at Forest City Optometry to schedule your routine eye exam.
