Choosing the correct types of lens for your vision problem can be tricky and confusing. There are many different types and the differences can be hard to completely understand. Lentricular and progressive lenses are two very common types of eyeglasses that are used. Each serves different purposes and helps to correct unique vision problems.
Information on Lenticular Lenses
1. How They Work
Lenticular lenses are corrective eyeglass lenses that are used in extreme cases. The shape resembles a fried egg, because there is a very high concentration of magnification in on small area. This is done in order to avoid having overly thick lenses. The portion surrounding the magnified center usually has little to no strength and is only there to support the center lenticular part.
2. What They Are Used For
Lenticular lenses are used in correcting of serious vision problems. The most common reason they are prescribed is for the treatment of extreme farsightedness. They can also be used for myopic corrections. They are also sometimes used for the correction of extreme nearsightedness as well.
High Plus : These lenses are trifocal that have between 10 to 15 diopeters centralized in the center.
High Negative : These are inverted versions of the high plus. With a lower power in the center and a higher prescription int he surrounding lense.
Bifocals : These types of lentricular lenses are used to treat people that suffer from both far and nearsightedness. The strength is split in the middle and person uses either the top or the bottom portion depending on what they are trying to see.
Information on Progressive Lenses
1. What They Are
Progressive lenses are lenses that have eliminated any visible transition lines. They have multiple strengths from the top to the bottom and are truly “multifocal”. You look up if you are trying to see something far away, look directly ahead for normal vision, and look down for close up views.
The first patent for progressive lenses was filed in 1907 by Owen Aves. He patented not only the design but the manufacturing process of them. Sadly Owen Aves never actually commercialized his product. That was done by Irving Rips in 1955 and they were called the Younger Seamless Bifocals. Major improvements have been made to the design since the 1980’s including better lens metrological technology and improvements in the modeling of the surfaces.
Progressive lenses have many pros, the biggest is that they are perfect for people with a variety of sight issues. They are also made to mimic the natural positioning of the eyes for certain vision situations. Image jumps have also been eliminated with progressive lenses, which are when things sharply change the way they look.
Differences Between Lenticular and Progressive Lenses
The largest difference between lentricular and progressive lenses is that progressive lenses are suited to multiple prescription strengths and vision needs. Lentricular lenses typically only have one focal point of magnification. Progressive lenses have multiple from top to bottom of the lens.
The design of the lenses are also extremely different. Progressive lenses are suited for multiple vision problems because of its design, they have different prescriptions on the upper portion for distance seeing, in the middle for intermediate vision, and on the bottom for close up. A lentricular lens only has a high strength in one centralized portion, usually in the center. The rest of the surrounding lens is either no or very little power.