Wearing prescription eyeglasses is very common in today’s world. In fact, there are more people who need corrective lenses to see clearly than those who do not. According to statistics supplied by the Vision Impact Institute, approximately 75% of Americans rely on some type of vision correction. If you are one of these individuals who need to wear glasses, you may be curious about the science behind lenses and how they trade in a distorted, blurry view of the world for one that is clear and defined.
The History of Prescription Eyeglasses
While it’s hard to imagine a time in history where people with poor eyesight had to live with blurry vision on a regular basis, the first pair of eyeglasses were not invented until the 13th century in Italy. These first glasses were not nearly advanced as what we have today and were essentially composed of two magnifying glasses connected with a bridge piece.
Several advancements were made to this technology over the course of several hundred years, including developing different lenses for nearsightedness and farsightedness and the addition of temple arms to the lenses to allow the glasses to stay on the face, leading to the development of eyeglass frames. In the late 18th century, the first pair of bifocals were invented. It was around the same time that John McAllister opened the first American optical shop.
The Anatomy of the Eyes
The eye is made up of several essential parts, which work together to allow humans to process their surroundings and see images. The first part of the eyeball which interacts with light is the cornea, which is the transparent, curved outer layer of the front of the eye. It serves the function of protecting other parts, such as the pupil and the iris. The pupil, the center black dot, then allows the light access the back of the eye while the iris, the surrounding colored area, controls how much light enters by causing the pupil to either dilate or shrink.
Next, the lens works to focus light onto the retina by either thickening or becoming thinner to focus on objects near or far. Once the retina receives this information, the photoreceptors within the retina, called cones and rods, can process the information and send it to the brain via the optic nerve to perceive a complete image.
Common Vision Issues
Most vision issues addressed by prescription eyeglasses fall into the category of refractive errors, which happens when the eye is not able to properly focus light onto the retina. As a result, the image sent to the brain is distorted and blurred. There are several factors that can contribute to refractive errors, including the shape of the lens, the length of the eye as a whole, and the curvature of the cornea. Refractive errors typically fall into four main categories:
- Myopia: Nearsightedness due to an elongated eyeball or a cornea or lens that is too curved
- Hyperopia: Farsightedness caused by an eyeball that is too short or a flattened lens
- Astigmatism: Distorted vision caused by an irregularly shaped cornea that may curve in one or more direction
- Presbyopia: Age-related farsightedness caused by inflexibility in the lens of the eye
Treating Refraction Errors
Vision problems caused by refraction errors can often be treated by prescription glasses, contact lenses, or surgery. There are several components that affect how a prescription lens is used to correct these problems.
Concave and Convex Lenses
Prescription lenses are categorized into either convex or concave lenses. Convex lenses address issues with farsightedness by converging light at a focal point and bending the rays towards the retina, instead of behind it. These lenses are thickest in the center of the lens and are identified with a plus sign on a prescription. Concave lenses, marked with a minus sign, are thinner at the center and correct myopia by diverging light.
For convex lenses, a stronger prescription places the focal point closer to the lens, and concave lenses require the focal point to be placed farther from the lens. The strength of the lens, or the spherical base strength, is measured in diopters.
Cylinder Strength and Axis
A cylinder measurement indicates the degree of astigmatism detected. To correct this issue, a cylindrical lens is used to focus the light into a single line. The axis measures the position of astigmatism in degrees.
Reading Glasses and Multifocal Eyeglasses
All adults experience some degree of presbyopia as they age. For people with no other refractive errors, reading glasses can be worn when reading or during other activities that make it difficult for people to see at farther distances. Multifocal lenses, which can be bifocal lenses, trifocal lenses, or progressive lenses, correct vision at multiple distances.
Living with less-than-perfect vision can make normal activities such as reading, using a computer, or driving difficult or near impossible to do. Explore our inventory of affordable prescription eyeglasses at Marvel Optics to find a new pair of corrective glasses you love.
How Do Glasses Work FAQs
How do prescription eyeglasses work?
Our eyes work by focusing light reflected by an image over several structures within the eye and brain that result in a clear image. Those whose eyes cannot focus clearly can wear prescription glasses that are designed to precisely focus light in a way that suits the specific needs of an individual.
What does a vision prescription mean?
A prescription for eyeglasses indicates the specific curvature and dimensions of the lens needed in order to help focus light over an individual’s eyes so that they can see clearly. Depending on an individual’s needs, there can be multiple aspects that make up a vision prescription and there may be differences between the left and right eyes.
Do you need a prescription to order glasses?
To order prescription eyeglasses, you will need a valid prescription from an eyecare professional. This ensures that the lenses are created with the correct specifications for your eyes. Wearing prescription lenses that are not right for you may be problematic as well as uncomfortable. Individuals who do not require vision correction can order glasses with non-prescription lenses without requiring a visit to an eyecare professional.
Can my prescription be read from my glasses?
An eyecare technician can use special tools in order to determine the prescription on a current pair of glasses. Prescriptions specifications are typically not written on lenses or eyeglass frames. The best way to determine your prescription is to visit your eyecare professional to have your eyes and/or current glasses checked. Alternatively, you could call your eyecare professional’s office to get the prescription if you do not have a paper copy on hand.
What is considered a strong prescription for glasses?
In general, the further your prescription strays from zero means that the prescription is getting stronger. Many frames for prescription eyeglasses can accommodate a variety of prescription strengths from very strong to very weak. However, some styles may have a more limited range, so be sure to read the descriptions on the products you like to ensure that they can accommodate your prescription.
Best Prescription Glasses
WileyX Profile
The WileyX WorkSight series of frames includes prescription-ready safety glasses. The Profile style has rectangular frames with full rims. Triloid frames and polycarbonate lenses meet the American National Standards Institute Z87.1-2010 high velocity and mass impact requirements and U.S. federal Occupational Safety and Health Administration 1910.133(b)(1)(1) standards. These glasses come with a fold-over case, removable side shields and a drawstring storage pouch.
Profile frames may be available in several color choices such as Gloss Brown Demi, Gloss Green Demi, Matte Hickory Brown, and Matte Black. This eyewear can accommodate single vision, bifocal and progressive lenses. Check the frame size and dimensions to determine whether Wiley X Profile can provide the best fit for daily, occupational or activewear.
ArmourX 6001
Another popular frame style ready for prescription lenses is ArmourX 6001. These plastic glasses with polycarbonate lenses meet ANSI Z87.1 safety standards. Large black rectangle frames wrap around the wearer’s face. While these glasses are compatible with single vision, bifocal or progressive lenses, the base curve may not be the best choice for high Rx lenses.
The 6001 style frames from ArmourX are suitable for on-the-job or activewear. A lightweight frame design is paired with lenses treated to resist dust, fog, reflections and scratches. When fitted with clear or tinted lenses, this eyewear provides protection from ultraviolet rays. This style is popular because it is comfortable and stylish enough to wear inside and outside while doing a wide range of activities.
Shellshore
A double bridge distinguishes Shellshore by Marvel Optics apart from other metal rectangular frames. This small feature draws attention upward toward the browline, which can be helpful for balancing the features of a round, oval, triangle or diamond-shaped face and adding an element of style. These full-rim glasses come in a small size and accommodate single vision lenses.
Rectangle-shaped frames with a double bridge are ideal for oval and oblong face shapes. Check the measurements of these frames to determine whether Shellshore is the right safety prescription glasses style for you. These frames may be available in colors such as blue, gunmetal or jet black.
M-Line Brave
Brave frames by M-Line have on-trend vintage styling at an affordable price. These round acetate full-rim glasses have spring hinges. Some versions combine black frame fronts and colored temples. Single vision, bifocal and progressive lenses can all be fitted into these frames, as can high Rx prescriptions. An anti-scratch coating maintains optical clarity for comfortable wear and value.
Check the dimensions of Brave frames to determine whether this style is the best choice for your face. Men and women can both sport this retro style. Choose from several shades such as matte black with navy temples, matte black with red temples and matte black. You can also customize this style with clear or tinted lenses.
Katelyn
One of the most popular prescription frame styles for women is Katelyn by Marvel Optics. These cat-eye full-rim frames are another vintage style updated for modern wear. Plastic frame fronts and temples feature textural details for a unique look. The best online prescription glasses for women are compatible with single vision, bifocal, progressive lenses and high Rx prescriptions.
If you have an oval or pear-shaped face, you may want to consider Katelyn frames. These glasses can be fitted with clear or tinted lenses with an anti-scratch coating for vision correction or sun protection. These glasses come in a medium size. Check the dimensions of this eyewear to determine whether it will provide the best fit. Marvel Optics makes more prescription-ready styles for women.
