Which Lens Material is Best for Your Eyeglass Prescription?

Boy, there’s nothing like a good old fashioned eye exam to chase away the blues. Pre-testing, dilation, an optometrist just inches from your face. And then, blurry from having unnaturally large pupils, it’s time to pick out frames and lens materials! Thanks to this mind-baffling process, it’s no surprise that we all wonder how we managed to spend $500 on one measly pair of glasses.

You see, many opticians (the folks that sell you the glasses) work for commission. Therefore, they will most definitely attempt to up-sell you into the most expensive lens material known to man. But how do you know what you actually need? By studying lens materials on your own time and making the decision before your appointment. This will allow you to present yourself in an informed manner – and likely save you some cash.

CR-39

Also known as basic plastic, CR-39 lenses are as inexpensive as it gets. Many optical retailers like Lenscrafters and Eyeglass World actually quote the frame price with this lens material in single vision included.

Benefits of CR-39 lens material:
Consisting of plastic, CR-39 lenses are much more lightweight than the old fashioned glass lenses. They provide decent optical quality and are generally affordable on most any budget. These lenses are the most easily tinted of all plastic lens materials, and much less likely to break than glass.

Disadvantages of CR-39 lens material:
With basic comes very few perks. Most optical retailers charge additional fees to add features like scratch resistance and UV protection to CR-39 lenses. While inexpensive, basic plastic lenses are not for everyone. Individuals with prescriptions over -2.00 or +2.00 can expect CR-39 lenses to become somewhat thick. Larger prescriptions can look forward to the “coke bottle effect”. Therefore, it’s necessary to select large, sturdy plastic frames in order to properly hold thicker lenses, as well as protect your nose from possible irritation.

Polycarbonate

A middle-range plastic, polycarbonate lens material is the best fit for most individuals, as it offers much more in terms of quality as opposed to basic plastic.

Benefits of polycarbonate lens material:
Lighter and thinner than CR-39, polycarbonate lenses are generally the most durable of all plastic lenses. They are less likely to break than other materials, and are often recommended to children, athletes and individuals with vision in only one eye as a protective measure. Polycarbonate lenses are typically offered by optical retailers with scratch resistance and UV protection included in the price. These lenses are ideal for moderate prescriptions and provide good optical quality.

Disadvantages of polycarbonate lens material:
As with most things, increased quality and protection comes with an increase in price. Polycarbonate lenses are more expensive than CR-39, sometimes costing as much as twice the price of basic plastic. These lenses are unable to hold dark tint, or anything beyond what most would refer to as a “fashion tint”. Polycarbonate lens material is sometimes known to cause color aberrations, or the appearance of a rainbow in the field of vision. Additional distortion is sometimes experienced by individuals with a high astigmatism. While these lenses are great for mild and moderate prescriptions, those with refractive errors exceeding -4.00 or +4.00 will have thicker lenses.

High Index

The highest quality of all plastic lenses, high index is oversold and sometimes even overprescribed to individuals that don’t require such quality, due to its fat price tag.

Benefits of high index lens material:
Providing the best optical quality of all plastic lenses, high index lens material’s clarity offers a dramatic improvement to all prescriptions. This lens material is ideal for large prescriptions, such as those above a -4.00 and +4.00, as it tends to stay quite thin regardless of prescription. High index lenses generally include scratch resistance and UV protection in price listed.

Disadvantages of high index lens material:
Due to its high optical quality, high index lenses are known to be extremely expensive. Insurance companies often fail to cover upgrades to this pricy material, causing consumers to pay more out of pocket than expected. This material does not hold any tint above that labeled “fashion tint”. High index lenses are often pushed on uninformed individuals as a last resort to improve clarity, which is oftentimes unnecessary.

Glass

Believe it or not, but glass lens material is still available through some optical retailers. This old fashioned material is typically purchased by those that have worn it exclusively for quite some time.

Benefits of glass lens material:
Contrary to popular belief, glass lenses actually provide the highest optical quality of all lens materials. Glass lenses are also the most resistant to scratches, which is why individuals with careers in farming and mechanical fields often prefer to stick with this material.

Disadvantages of glass lens material:
Due to the fact that high end plastic materials have taken the optical market by storm, glass lens material is not as readily available as it once was. This has caused the price of glass lenses to increase, as well as the turn-around time for production. Glass lenses are among the heaviest and thickest of all lens materials, and are more likely to cause serious injury if breakage occurs.

Sources:
Optical training with National Vision, Inc.
http://www.eyes-and-vision.com/eyeglasses.html

Reference:

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