1.67 vs 1.74 High Index Lenses – What You Need to Know
Shopping for eyeglasses can be complex. So many variables play into the equation that, unless you’re an expert, you often don’t know what to choose in order to maximize your opportunities and get exactly what you want and need. So, too often, you choose an option that’s not actually ideal for your needs and wants.
That’s especially true when it comes to high index lenses. The concept itself can be confusing for anyone not used to these types of lenses. And yet, even within that concept, there are a number of distinctions you absolutely need to know in order to find a pair that matches your exact needs.
How do you know what to pick? Where do you even start? One of the most basic differences within this category is the distinction between 1.67 and 1.74 lenses. This article will more closely examine that difference, before going into the various reasons you might want to pick one option over the other.
Back to Basics: High Index Lenses
Lens materials never stop evolving. We’ve certainly come a long way from the thick glass that defined vision enhancement options for people who needed it. Today, new technologies allow for more distinction, clearing your vision even on strong prescriptions without acting as an impediment or fashion faux pas.
Take high index lenses as an example. The basic function of any lens is to bend the light as it passes through the glass (or plastic). As a result, it corrects the vision that requires prescriptions. The stronger the prescription, the more the light needs to be bent.
In addition, most lenses are not equally thick across the spectrum. Instead, if you’re near sighted, they are thinner in the center and thicker on the edges to make up the difference. If, on the other hand, you’re far sighted, your lens will typically be thicker in the center and thinner on the edges.
That, in turn, introduces a number of problems. Above all, as your prescription strength increases, your glasses need to keep getting thicker. But that is only the case with regular lenses. High index alternatives, on the other hand, are designed to keep the thickness to a minimum. Even better, they’re more efficient at bending the light across the entire lens, so that it can evenly thick on both the edges and the center regardless of whether you’re near or far sighted.
The Basic Difference Between 1.67 and 1.74 High Index Lenses
Because of the above reason, many individuals who wear glasses choose high index lenses as their prescriptions become stronger. Doing so helps you not just keep your glasses light, but also thin. As a result, glasses with this lens type tend to be much more attractive to people with strong prescriptions who don’t necessarily want to show off their failing eyesight.
But even as you choose high index lenses, your options are not done yet. As it turns out, not every material or option in this area is created equal. Far from it. Instead, you can choose from various indexes as you pick the perfect pair of prescription glasses for your needs.
Generally speaking, that index ranges from 1.5 to 1.74 and even above for any type of eye-wear. A standard plastic is about 1.5, and glass is about 1.51. High-index options start at 1.53, though at this point, the difference to regular eye-wear is minute. The higher that number, the thinner the lens will be even with the strongest types of prescriptions.
And that is the basic difference between 1.67 and 1.74 high index lenses: the latter is simply thinner, and lighter, than the former. Lenses with a refraction index of 1.7 or higher are at least 50 percent thinner than those with a regular index.
When Should You Go For 1.67 High Index Lenses?
With a basic definition of the difference between both options out of the way, it’s time to more closely look into the reasons you should choose one or the other. Let’s start with 1.67 high index lenses, a common choice in a number of scenarios.
Choose a 1.67 refraction level if your prescription is still at medium level, but rising. Typically, that means a prescription between -6.00 and -8.00 diopters. At this level, you will begin to think about thickness as you evaluate your next pair of glasses. High index options become a relevant consideration.
But you don’t need the highest index quite yet. Choosing it would mean spending considerable money, while the return is not necessarily there. 1.67 refraction index glasses offer a great mix of price, durability, and convenience for your needs at this level.
This option might, for example, appeal to a middle-aged female who wants to dress professionally in an executive-level job. Regular plastic glasses might no longer serve her needs well, because they are becoming thick, heavy, and uncomfortable. High index glasses at the 1.67, on the other hand, offer just the right amount of durability, thinness and light weight without breaking the bank.
When are 1.74 High Index Lenses a Better Choice?
Of course, you might find that 1.67 index glasses no longer work well for you. They are significantly than plastic or regular glass options, but will use their utility at some point. When that happens, it’s time to look at other alternatives that can do a better job while maintaining both fashion and function utility.
Most eye care professionals will recommend looking at this option when your diopter level goes beyond -8.00. Now, high index glasses with lower refraction abilities might no longer do the trick. Instead, you might once again begin to suffer from a lack of comfort, distortion around the edges of your lens, or glasses that just do not look the part anymore.
This is where the more relevant 1.74 refraction index enters the equation. For high index lenses, it’s the highest you can go. In other words, you absolutely minimize the problems you might experience with weight or thickness in the process. Instead, you get a pair of glasses optimized for strong prescriptions.
To stay with the above example, imagine that same professional getting a promotion to CEO. But her eyesight is getting worse. At the first board meeting, she needs to look professional regardless. 1.74 high index lenses are the perfect choice to help her accomplish her goals. They might cost more than the 1.67 refraction alternative, but that added cost comes with significant utility, style, and function advantages.
Adding Lens Options to Your High Index Glasses
Of course, even choosing whether 1.67 or 1.74 works better for you is only the beginning. Your next consideration should be considering exactly what type of lens additions and improvements you want and need to maximize their utility.
Take anti-reflective coating as an example. As a general rule, high index lenses block significantly more light than regular plastic or glass alternatives. But they might still need additional help to minimize the reflection on your glasses. Anti-reflective coating ensures that you can still see clearly, even in glaring sun.
In addition, most lens options also include the ability to add high index materials to them. For example, you can get your progressive lenses or your transition lenses with a higher index. As you minimize the negative effects of bifocals and turn your regular glasses into sunglasses, you can still benefit from the light weight and lack of thickness that high index lenses can provide.
Finding the Perfect Lens Option, Material, and Quality for Your Vision
All of the above are clear benefits for choosing this type of lens for your needs. But of course, you can only realize them if you go through the process the right way. Simply put, you cannot simply buy the first pair of glasses online, and hope for the best. The process needs to be more strategic.
First, that means getting an updated prescription from your eye doctor. Without it, you might not even know if you need high index lenses to begin with. In that process, it also makes sense to ask the professional what refractive index they recommend for you. That alone can help you make the tough decision of choosing 1.67 over 1.74 or vice versa.
Next, consider the context. We’ve already discussed some potential add-on choices above, and they are not the only ones. Make sure you understand exactly how you can enhance your lenses for maximum utility to your unique needs before you buy them.
Another piece of the context is the frame you want. High index lenses now fit in most frames, but it never hurts to double-check. Before you fall in love with a specific frame, make sure that it can actually fit the lens you need for optimum vision and comfort.
Finally, only buy from credible merchants. This might be the most important step in the entire process. Without it, you risk buying an expensive pair that doesn’t hold its promise. Instead, look for warranties, returns policies, and user reviews to find a merchant that’s credible. As long as you do that, you can make your next pair high index prescription glasses and optimize your vision moving forward.