Reading Glass Prescription

A pair of reading glasses is a lot like a pair of shoes; they feel great in the store, but after wearing them for a few hours, the problems show up. They may be too tight and pinch, or rub you in the wrong spots. They may be too heavy, causing them to slide down your nose. Pretty soon your glasses end up tossed in a drawer, and you’re stuck with a headache as you squint and strain. Choosing the right frame and lens is essential to the comfort and successful wear of your glasses. Read on to learn how to make the best choices for your prescription, fashion sense and lifestyle.

The Prescription

The prescription that your optometrist or ophthalmologist hands to you written on a piece of paper tells an optician the exact strength of the glasses you will need. There are four basic measurements: the sphere power, the cylindrical power, the axis, and the PD, or pupillary distance. If you need bifocals, there will also be an additional power written for those. All the powers in a pair of glasses are expressed in diopters. So what does all that mean, exactly?

A typical prescription looks like this:

OD -1.25 -1.00 x 90

OS -2.00 -1.25 x 94

+2.00 ADD PD 64/61

OD is a Latin abbreviation meaning oculus dexter, or right eye. OS, oculus sinister, signifies the left eye. The prescription for the right eye is always written first. In the above example, the prescription signifies that the person is near-sighted with a fair amount of astigmatism, and needs bifocals reading glasses.

The first number written, -1.25, is the sphere power. This sphere power can be written for near or far-sighted powers, and measures how much near or distance power a person needs to see clearly.

The second and third numbers, -1.00 x 90, measure astigmatism, and are read in combination. The second number, called the cylinder, measures how many diopters of astigmatism a person has, and the third number is the axis. The axis tells the optician where in the lens to place the cylindrical power. The axis is measured in degrees, and can be any number between 1 and 180. Astigmatism means that the eye is not perfectly rounded, but shaped more like a football, and causes blurred vision. Most people have both sphere and astigmatism correction.

The next number, +2.00 Add, signifies that the person also needs correction to see close up, or needs reading glasses. The Add power is almost always the same in each eye. Everyone will eventually need glasses for reading or close work. As the eye ages, the elasticity of the eye’s lens decreases, making it harder and harder to focus on near objects. The technical term is presbyopia, also called “long-arm sight,” because a presbyope will start holding reading materials out at arm’s length in order to see them. Presbyopia is usually noticed around 40 years of age, and it happens to everyone.

Finally, the PD, or Pupillary Distance, is the distance from the center of the right pupil to the center of the left. Often, this is measured when you are fit for glasses by the optician, rather than by the doctor. The PD measurement is taken to ensure your lenses are centered directly in front of your line-of-sight. You will see most clearly through the direct center of the lens.

The Lenses

Lenses come in two basic styles: single vision and multi-focal. A single vision lens is prescribed for a person who only needs distance or near correction, with or without astigmatism. A multi-focal lens can be a bifocal, trifocal or progressive style.

Single vision lenses are the least expensive because they only have one focal area. Multi-focals have two or more focal areas, and are for those who need distance as well as near correction. Bifocal lenses have a distance power on top, and then a lined segment that contains the reading power below. A trifocal has an additional intermediate distance, resulting in a lens with two lines. A progressive lens, also called PAL’s or no-lines, have many focal areas, allowing the wearer to see near, far, and most points in-between with ultimate clarity.

In addition to focal styles, lenses also come in different materials. Lenses are available in glass or plastic, as well as many light-weight or safety options. If you have a heavy prescription or are bothered by regular sunglasses due to the weight, you should choose a light-weight lens. Polycarbonate is a popular light-weight material, and has the additional benefit of shatter-resistance, making it an ideal lens for safety glasses, children or athletes.

Lenses can also have coatings applied to make then scratch-resistant (no lens is scratch-proof!), filter ultra-violet rays and reduce glare. All three of these options are recommended for every pair of glasses, as they improve the safety and performance of the lenses. Additionally, lenses may be tinted, polarized, mirror-coated, or made to darken outdoors and lighten indoors. A conversation with your optician about your needs and lifestyle can lead you to choosing the right options for your first pair of glasses.

The Frame

Choosing the right frame can be the difference between glasses that live on your nose and glasses that live in a drawer. A good frame should be lightweight, strong, fit comfortably and suit the wearer’s sense of style.

Plastic Frames vs. Metal Frames

Plastic frames in classic shapes with bold colors are quickly becoming a fashion favorite. Gone are the tortoise and horn-rimmed clunkers you may associate with plastic frames; today’s colors are a veritable rainbow of choice.

Plastic is a stylish and durable choice, and as the frame itself is often thicker than a metal one, plastic frames hide thick lenses better than thin metal frames do. Plastic frames usually do not have adjustable nose pads, making them more prone to sliding down the nose. Plastic frame are also less adjustable; the way they fit when you first put them on is the way they will fit after your lenses have been inserted.

The drawback to plastic is the ease with which the frame material stretches. Plastic frames that are worn on top of the head or are taken on and off frequently tend to lose their shape faster than their metal counterparts. Plastic frames are also a poor choice for sunglasses, which are often left in a hot car during the summer. Heat will cause a plastic frame to expand and contract, bending it out of shape and wearing out the material more quickly. When a plastic frame is broken it is not as repairable as a metal frame, which can be soldered.

The Benefits of Metal Frames

Metal frames are popular due to their sleek profile, thin rims and classic appearance. Metal frames are also more forgiving of the abuses commonly committed by the new wearer.

Today’s metal frames offer a variety of lens shapes not achievable in plastic materials, and can generally be custom fit to the wearer. They are easily adjusted or bent back into shape after an accident. Most metal frames have adjustable nose pads on metal arms soldered to the frame itself, allowing the pads to be fit to the individual nose. Different nose pad styles can cause a frame to sit higher or lower on the nose according to need, and can reduce slippage and improve overall comfort.

Though metal comes in many colors beyond basic gold and silver, the overall look is sleeker and less noticeable than a plastic frame. Metal frames are also more light-weight and can be readily adjusted for comfort. Some metal frames are available in a flexible metal alloy that snaps back from a hard twist without kinking or damaging the frame. Titanium metal frames are strong, lightweight, and won’t cause skin irritation.

Which Frame is Best for You?

If you only need reading glasses or plan to remove your glasses frequently, choose a flexible metal style that will not stretch out of shape. Flexible metal is also best for those who work outdoors, athletes, or anyone who is likely to have their glasses knocked off their face.

If you like bright and bold colors, a plastic frame will offer the most color impact.

The look of a very long nose can be shortened with a plastic frame. Plastic frames are often more comfortable for those with a flatter nose bridge.

If you’d rather not look like you’re wearing glasses, choose a thin metal frame in a color that complements your skin tone. Soft colors like peach and rose blend with almost any skin tone, reducing the appearance of the glasses.

Heavy or thick prescriptions benefit from a lightweight lens and frame. If the sphere power on your prescription is more that +/-3.00 diopters, opt for thinner, lightweight lenses, such as polycarbonate or a hi-index material.

If you have very pale skin and don’t want your glasses to stand out, choose a light-colored metal like silver. If your skin tone is darker, a darker color like burgundy or black will blend better.

Proper Fit

The right pair of reading glasses should rest gently on your nose, and your eye should sit in the center of the lens. The nose pads should follow the plane of your nose, and not sit too far above or below your eye.

Large lenses are not necessary; lenses that cover your eyebrows offer no visual benefit. Lenses that rest on your cheeks when you smile are too big. It’s okay to be able to see over your lenses, but they should offer enough visual area for you to see without having to slide the glasses up or down. If you wear bifocals, you will not be able to wear a very narrow lens, but there’s no need for a very large one, either.

The temple arms should sit comfortably around the bone behind your ear without squeezing the side of your head. Temple ends should not pinch or be too tight. Nose pads should not leave deep impressions on your nose or be splayed too far apart. The glasses should not slide down your nose or rest so close to your eyes that your eyelashes hit the lenses.

The bend of the temple arm should begin directly behind your ear. One of the most common fitting mistakes is choosing a frame that bends too soon, which causes the back to rise and the lenses to drop onto your cheeks. Temples are available in many lengths, and can be special ordered or even cut to fit.

Kids and Glasses

If your child needs reading glasses, be sure to explain to them how important it is to take proper care of them. Glasses should be removed using both hands to grasp them at the temples. Provide your child with a hard case, especially if the glasses spend any time in a backpack or bookbag.

Reading glasses should never be shared or tried on by a child’s friends. Your child’s glasses have been adjusted to fit their face properly; sharing them can bend them out of shape or loosen the fit.

Many people believe plastic reading glasses are more durable for kids. This is not so; flexible metal offers the best durability and is available in children’s styles. It can also be beneficial for a child to have two pairs of glasses. This allows the child to leave one pair at home and one at school, minimizing the chances of loss.

The best pair of reading glasses for your child is the one they like well enough to wear. If your child is uncomfortable in their glasses, they won’t wear them. Let them choose their favorite color or the one that feels the best to them, even if it’s not what you would choose. Many children’s frames now have favorite cartoon and movie characters on them. Some even glow in the dark!

How to Care for Your Reading Glasses

No matter which style you choose, some basic care will be required to minimize lens scratches and keep the frame and nose pads clean.

• Wet lenses on both sides before wiping clean
• Always use a soft, 100% cotton cloth (not a shirt!)
• Launder the cleaning cloth regularly to remove debris
• Always use an approved cleaner, or soap and water
• Wash the entire frame in warm soapy water when dirty
• Have plastic nose pads replaced often
• Always store glasses in the case provided
• Never leave glasses in a hot car or direct sunlight
• Have your glasses adjusted every few months to ensure comfort

If your glasses become loose, crooked or bent, bring them to an optical shop to be repaired. Bending them yourself can cause breakage. The best cases to store glasses in are hard on both sides. Soft, flimsy cases offer less protection. Never use harsh household cleaners on your lenses. These can strip the protective coatings and cause damage.

Even if you’ve sat on your glasses, or they’ve been chewed up by your puppy, bring them in to be looked at before you toss them away. Often they can be restored to wearable condition in the hands of an optician.

With proper care and the right frame and lens combination, a pair of glasses can last for several years. Taking a little extra time when choosing a frame can pay off in comfort and durability, and make your glasses more enjoyable to wear.

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