Anyone who wears glasses covets lighter and thinner frames over heavy cumbersome frames. It is possible to make high index eyeglass lenses as much as 50% thinner than lenses made of plastic or traditional glass, and the wearer will commonly find such glasses are lighter to wear.
The light index lens material is more visually pleasing and practical. The lenses are beneficial if a person has a very strong prescription for eyeglasses, but still wants a lightweight frame. With high index lenses, light bends with greater ease, in fact better than it does with plastic or glass lenses. Basically, this means that you can use less lens material and have thinner glasses as a result.
The price points associated with high index lenses differ greatly and are based on the thinness of the lens as they compare to conventional lenses crafted out of plastic. The lenses are categorized by refractive index, otherwise called the index of refraction.
If the refractive index is higher on a set pair of lenses, the items will have a thinner structure. The thinner the lenses, the higher the costs, especially when compared to lenses with a lower refractive index. For regular lenses made of plastic, 1.50 is the refractive index. Ranges between 1.53 and 1.74 are associated with plastic high refractive index lenses. The lenses that range between 1.53 to 1.59 are actually a full 20% thinner than traditional lenses made of plastic. Meanwhile, the high index lenses in the 1.74 range are about 50% as thick as standard plastic eyeglass lenses.
Some of the most coveted lens styles, including photochromic, progressive, bifocal, and single vision, are available in materials consisting of a high index. You must speak with your eye doctor to find out if your prescription is available in high index material. Trifocals and bifocals are also crafted with high index materials, however, the selection you have will be somewhat limited.
Note: If you opt for high index lenses we recommend that you also opt for anti-reflective coating (AR coating) as well, since high index material has a tendency to reflect light to a greater degree than traditional lenses.
Aspheric Lenses with a Slim Design
An aspheric design is used to increase the visual elements of high index lenses. Rather than featuring a spherical or round structure for the front surface curve, the high index lenses are crafted with a gradually-changing curvature moving from the lens’ center to its outermost edges. Thus, the lenses feature a thinner, lighter, slimmer, more visually pleasing profile.
The aspheric design offers some benefits for every kind of prescription, and this is very true for those who get the lenses for correcting farsightedness. Theses lenses with aspheric structures reduce the “bug-eyed” effect that a regular lens curvature produces. What’s more, the bulge of the lens frame is minimized, and the wearer’s peripheral vision is greatly improved, especially when compared to traditional eyeglasses.
Please Note: Aspheric lenses feature flatter curvatures that are prone to producing reflections that the lens wearer may find noticeable. Once again we highly recommend the couple of AR Coating features with aspheric lenses to reduce reflection and glare.
Durable Lenses – Trivex & Polycarbonate
Trivex and polycarbonate high index eyeglass lenses offer the wearer lenses that are highly resistant to impact. In fact, if you compare Trivex and polycarbonate lenses with other lenses, they are ten times stronger than plastic lenses: This being the case the lenses are perfect for children who may be a bit rough on eyeglass wear, and for anyone who participates in sports or lives an active life. The lenses are safe, light, and allow for thinner eyewear as well.
Trivex lenses are thicker than the lenses crafted out of polycarbonate. The impact resistance level of both style lenses is the same. What’s more, both style lenses help in blocking out 100% of harmful ultraviolet rays. Polycarbonate lenses are roughly 30% lighter and 20-25% thinner than regular lenses and have a 1.59 refractive index. If you have a sensitivity to heavy eyewear, polycarbonate lenses are an ideal selection for you.
Improve Vision with AR Coating
Lenses for eyeglasses are reflective, but will not allow all light to enter into the eye. Due to this fact the visual images that form in the eye are not perfect and the reflective properties in glasses and reduce one’s visual acuity. The effect on one’s vision is definitely effective if the lighting in the environment is low or during times when you are night driving. The reflective properties of lenses can cause issues with glare, which further lends to issues with vision during certain conditions.
The lens material used to craft the lenses defines how reflective the lenses are; plastic and conventional lenses will reflect roughly 8 percent of the light striking the lenses’ surface, thereby making roughly 92% of the light accessible to the eye for visual interpretation. If the lenses are high index, thinner, and lighter, they can reflect as much as 50 percent more of the light that strikes’ the surface of the lenses, when compared to plastic and conventional lenses, which allow for about 12 percent more available light.
AR coatings or anti-reflective features minimize the light the lenses reflect and, therefore, allow more light to get through the lens into the eye for visual interpretation. Whatever material is used to create the lenses makes no difference because AR coating makes it so as much as 99 percent of the light gets into the eye for visual interpretation.
AR coatings eradicate issues with reflections and also helps in lending an element of invisibility to the lens as well. Thus, the appearance of your lenses improves and lets others really look at your eyes rather than your glasses and the reflections cast on the lenses’ surface.
Your optician while guide you on how to clean your lenses if they feature an AR coating. You want to take considerable care not to get any scratches on the lens as such scratches will be more visible than if scratches that appear on lenses absence of the AR coating.
There is no such thing as scratch proof lenses, no matter what material your lenses are made of; Nevertheless, you can get lenses with a special treatment that is applied to the back and front of the lenses. The treatment will help make your lenses scratch-resistant, and my prevent scratches from occurring if your lenses are accidently dropped, or if they are cleaned with a rough paper towel or other material. Children can always benefit from scratch resistant lenses.
If you have polycarbonate lenses, the manufacturer adds a coating of scratch resistant material – this is true of many high index lenses. The scratch resistance makes the lenses more durable. It’s a good idea to have the scratch resistance feature to any lenses you buy as a way of protecting your investment.
We recommend you store your glasses in a protective case whenever they are not in use. We also recommend that before you clean your eyeglass lenses, you rinse them off with water or a cleaning solution. If you dry clean the lenses you are rubbing dirt, dust, and other debris against the lenses surface. In doing so, you run the risk of scratching them – this is true even if you opt for a scratch resistant coating.
Protection from UV Rays
Your eyes require protection from ultraviolet rays, just as your skin requires sunscreen. There are lenses that can block out ultraviolet rays so your eyes remain protected. Excessive exposure to UV rays is cited as one of the causes of a number of eye conditions, including retinal damage and cataracts. If you opt for high index lenses, they usually offer 100% UV protection. With other lenses, however, a treatment needs to be applied to make them block out harmful UV rays. The treatment is very expensive and does not change how the lenses look.
Photochromic (Transitional) Lenses
When you wear lenses that change from regular, clear lenses when indoors to tint lenses when you go outdoors, you are wearing photochromic lenses. Such lenses offer 100% protection from UV rays. You can get photochromic lenses as progressive lenses or bifocals in an array of designs and styles. The shade of tint you get depends on what you choose, and the tint will darken to a degree that is dependent on how much UV light strikes the lenses. If you are driving, your lenses will not change color as a general rule since the windshield already blocks out much of the UV rays from the sun.
Let Us Guide You!
We understand that when it comes to lenses you have so many options. The lenses you need will be dependent on your visual health and your budget. We are happy to help you explore your options, and invite you to come discuss your options with one of our trained vision specialists. We will help you find the perfect lens wear solution for your needs.