1.67 high-index lenses surpass in thinness and lightness when compared to 1.61 high-index lenses. It helps with eye distortion caused by stronger prescriptions and is ideal for individuals with an SPH correction between +/- 7.00 and +/- 9.00, and a CYL correction between +/- 3.25 and +/- 4.00.
What is the difference between 1.6 and 1.67 lens?
A mid-index lens of refractive index 1.6, approximately 20% thinner than a standard lens. A high-index lens of refractive index 1.67 will be approx. 33% thinner , whereas a lens with a refractive index of 1.74 will be around 42% thinner.
Is 1.61 A high-index?
High-index lenses have good optical clarity, 100% UV protection, and excellent durability. They currently come in indices of 1.61, 1.67, and 1.74. All three lenses are made with similar materials, so the choice of index comes down to your prescription strength. A 1.61 high-index lens is best for +5.00/- 7.00 or above .
Are 1.67 lenses worth it?
The difference between 1.67, which is considered regular index and 1.74 is quite small, and really, the only way you’ll notice the difference is if you have a prescription below a -6 or above a +4. However, if you are in need of a very strong prescription, it is absolutely worth the additional cost!
What index lens do I need?
A high-index lens may be recommended if your optical prescription is above 2.00 diopters. High-index lenses have a refractive index above 1.50 — ranging from 1.53 to 1.74. The image below compares the lens thickness of a regular plastic lens (1.50) to the most commonly prescribed high-index lenses.
Is there a big difference between 1.67 and 1.74 high index lenses?
1.74 high index lenses are thinner and lighter than 1.67 high index lenses . ... Though both reduce the eye distortion caused by strong prescriptions (making your eyes look bigger or smaller than they are), 1.74 high index lenses accomplish this better than 1.67 high index lenses do.
What is the thinnest lens for high prescriptions?
1.74 index lenses are the thinnest lenses for high prescriptions available. These ultra-light, ultra-sleek lenses are the thinnest kind developed yet, and accommodate the highest prescriptions possible.
Do high index lenses make eyes look smaller?
We think this is probably where the misconception around them is why people are asking whether high index lenses make their eyes look smaller. The short answer is no, they won’t.
How can I tell if my lenses are high index?
There are no telltale signs to distinguish high index lenses from standard material lenses; no industry-required stamp or barcode to set high index lenses apart. For the most part, confirmation is a matter of visual inspection.
What is the highest index for glasses?
The Highest Available Index
1.90 is the highest index lens available. Since any high index lens at or above 1.80 are made of glass only, 1.90 lenses are, obviously, available only in glass and not in the plastic high index format.
Why are high index lenses so expensive?
Why does all of this matter? Ultimately, high index lenses are more expensive than other types of lenses due to their inherent material . The material that is used to produce high index lenses is from a chemical synthetic blend, and the cost to simply produce sheets of the material is high.
Are high index lenses worth the money?
In less technical terms, this means that high index lenses are better at bending light rays for vision correction . As a general rule of thumb, the higher a lens’s refractive ability is, the less material is needed to achieve a particular prescription strength.
What prescription is legally blind?
Eye prescriptions are given depending on the severity of correction needed to restore normal vision. Normal vision is 20/20. The U.S. SSA uses the term “legally blind” in people whose vision is 20/200 with glasses or contacts , or whose visual field is 20 degrees or less than the normal eye.
What are the thinnest high index lenses?
1.74 index lenses are the thinnest eyeglass lenses for high prescriptions. These ultra-light lenses are the thinnest kind developed yet, and accommodate the highest prescriptions possible. They’re much thinner and lighter compared to 1.67 index lenses, and offer a certain level of cosmetic value too.
How thick is a 1.67 lens?
1.67 ( Thinnest and Lightest ) 1.74 (Thinner and Lighter)
Are Bluelight lenses worth it?
The American Academy of Ophthalmology says you don’t need them and has gone on record as not recommending any kind of special eyewear for computer users. The organization says blue light from digital devices does not lead to eye disease and doesn’t even cause eyestrain.
