Choosing the Right Index for Your Glasses
The index rating for your glasses is more important than you might initially think. The higher the index, the more efficient it’s going to be at helping you correct your vision without a lot of extra material.
Where to Begin
It’s obviously not the case that index is the only thing you need to worry about when it comes to pick glasses whatsoever, but it is an important consideration without a doubt. Not all index types are going to appeal to all people, and there’s definitely a sense in which different people with different needs are going to gravitate to different types of glasses.
Essentially, you have to choose where your areas of highest needs are going to be. If you care more about how the glasses look including from the side perspective as well as the distortion that high prescriptions have when looking dead-on, there’s going to be a particular index that will appeal to you the most. If you have concerns more about aesthetics instead, then
Lower Index (1.5-1.57)
Compared to high-index lenses, the more standard glasses have a low index of 1.50 for plastic lenses and something like 1.52 for those with glass. The advantages here include the following:
- Less Expensive-It is true that in many situations, the standard lenses with the standard index are going to be less expensive. This isn’t absolutely universal of course, but it Is true that the trend has a tendency to be in this direction.
- Easier to Locate-A lower index for glasses is also going to be easier to find since it’s standard. It may not be the case that every place you go to in order to find glasses is going to have a higher index. So, if you need glasses right now or for the short-term especially, then you may want to settle for the lower index in general.
- Higher Familiarity-Techs may also have a higher familiarity with glasses that use this type due to its common nature. Having thin glasses that have the higher index and that don’t have to use additional layers of thickness may be beyond what some professionals know how to handle.
- Sufficient for Significantly Low Prescriptions (-2.00 Diopters)-The recommendation is that if you have a really low prescription, then you really may not need the advantage associated with higher indexes. In this case, you can go for the lower index and save a little bit of money at the same time.
Higher Index (1.61-1.67 index)
For those who have a prescription that starts moving up the scale at -6.00 diopters, you may want to try out the higher index glasses such as the 1.67 version. If you have lenses that are a bit thicker either on the edges or in the middle, upgrading to lenses that have this type of index could be of considerable significance.
Here are some of the characteristics of the 1.67 index lenses that help to differentiate them from the other lens options:
- Medium Thickness-Unsurprisingly, lenses with this index having less thickness than the lower index rating lenses, but more than what you would get at 1.74. If the thickness is a bit of a problem for you in your standard glasses, but not a top priority, this could be the right index, in other words.
- Style/Color Options-There are often different options for colors and styles between the 1.67 lenses and the others, so it’s a good idea to check this if this element is significantly important to you. This will obviously vary based on where you buy them, but generally, these lenses have more colors than the higher index ones, including the brown tinted ones, the gray tinted version, totally clear or the special transition lenses which you can choose gray or brown depending on what you like.
- Appearance-Maybe you like a little bit of thickness in glasses as long as they aren’t too thick. Since these lenses are going to be a bit, but not maximally so, you might like them if they are in the middle.
- Medium Weight-Again, if the standard glasses you have sit just a bit too low on your nose and or only sliding off sometimes, in certain situations, then an index like this might be the one that works.
It’s also worth noting that the 1.67 lenses are often the only choice you have if you want the Transition type that can go from sunglasses and back automatically depending on the sunlight. If you want both this effect as well as the high-index, then you have to stick with 1.67, depending on the store.
High Index (1.74 and Higher)
There may be glasses that have a higher index than 1.74 at some point, but in general, these are the highest that you’re going to get. Some of the reasons you should go for this index level include the following:
- Distortion Correction-Glasses with a high enough prescription for corrections tend to have the effect of making your eyes look either larger than normal or smaller than normal depending on whether you’re farsighted or nearsighted when it comes to people look at your eyes. However, a high index option like this one allows you to reduce this effect so it’s virtually invisible. Again, this effect will only be particularly bad for very high prescriptions.
- Eye Strain Reduction-There have also been reports that if you have a high enough prescription that has a lot of optical distortion, this could aggravate eyestrain as well. However, the highest index lenses can help you with this by reducing the strain with the efficiency of just about the thinnest high prescription glasses you’ll be able to find.
- Highest Comfort-You’ll end up with the lowest weight and thinnest profile of these options if you go for this index level. Those with the highest prescriptions could find this to be a lifesaver due to just how much it tends to reduce the way thick glasses press on your nose and weigh down your face.
It’s also worth noting that the 1.74 high index lenses are going to be the most ideal for those who have a prescription coming it at -8.00 diopters or more. Spending the extra amount here is definitely going to be worth the extra cash considering what the alternatives tend to be in terms of trying to have something that corrects at higher prescription without as much of an index for the lenses.
Overall, the important thing is to make sure that you’re going to be personally comfortable with whatever glasses you choose, including both the index of the lenses and the other aspects of the glasses like the material, frame type, and other factors. There are a few ways that you can do this, including making sure that you explore what lens index works for which general preference. For example, you can also try to head to places in person before you commit to buying anything in order to see how the high index lenses and frames actually feel on your head. Additionally, some online sites will allow you to get the frames in the mail and try them on for a few days while still having the option to send the back if it turns out that you don’t like them so that you aren’t stuck. This obviously varies from site to site.