WHAT ARE PROGRESSIVE LENSES?
Progressive lenses (PALs – progressive addition lenses), often called multifocals, are lenses that are used to provide good vision at distance, intermediate and near distances at the same time. It should not be mistaken for an invisible bifocal or trifocal. At the top of the lens, there is the distance prescription, which gradually increases in power (hence, “progressives”) to the near portion of the lens at the bottom, which is one’s full reading power. A progressive lens is common amongst an aging population where reading glasses are generally warranted. It is a multipurpose lens that can be used for driving, using the computer and reading, without the need to change the glasses. How good is that?
HISTORY OF PROGRESSIVE LENSES
Progressive lenses have come a far way. The first version of a multifocal lens was the Franklin bifocal, created in the 1780s, which was a lens where a slab of refractive material (glass) was stuck onto one’s distance prescription lens to create the near proportion for reading. This eventually paved the way for the first progressive, whereby it became a race between lens companies in Paris and East Berlin in the 1950s to create the first progressive. Eventually, the first progressive lens was invented in 1959 by Bernard Maitenaz and was used to correct the same condition, presbyopia, where the aging eye is unable to view objects up close (it will happen to everyone!). Progressives now have revolutionised vision, and helped to incorporate together a multidistance lens which is both multifunctional, and reduces the need for switching between different pairs!
ADVANTAGES OF PROGRESSIVE LENSES
If the fact that not having to swap your glasses for near and far work wasn’t good enough, there are more advantages to progressive lenses! Another benefit to progressive lenses is that there is no distinct line, like bifocals, that indicate a change in lens prescription. Some wearers are quite wary of the visible line of the lens, as it may be indirectly associated with old age. There is also no image jump in your vision.
DISADVANTAGES OF PROGRESSIVE LENSES
Progressive lenses are truly a remarkable piece of engineering as three prescriptions are combined in the one eyepiece. However, it is not without its kinks. Due to the incorporation of multiple prescriptions within the one lens, there will be areas of distortion in the lens. In the bottom two corners of the lens, there is what is called a “swimming effect” where the contours of the world will look distorted and dizzying. The size of these areas of distortion will depend on the lens design selection you make with the lens company. They will never be in your central field of vision. In fact, with good adaptation and viewing habits, you will not even notice these areas when wearing progressives at all!
At Eyecare Network, our lenses are Japanese-designed, custom lenses which offer 3 tiers of progressives, Dynamic Premium, Lifestyle V+ and Mystyle Profile. Of the three kinds, Mystyle Profile is the most premium lens design, and offers the least amount of lens distortion in the periphery. It is a fully unique lens where the distance, intermediate and near regions can be customised based on the wearer’s specific needs.
EXTENDED FOCUS LENS
An extended focus lens is another form of PALs, but with a different purpose. The extended focus lens is used primarily for reading and computer use, being that there is an intermediate portion at the top of the lens which increases to a near portion at the bottom of the lens. Again, the extended focus lens can be customised for a range of intermediate distances. They are primarily beneficial for office workers, and people who use the computer a lot during the day.
If you are considering your first pair of progressives lenses or simply want to upgrade from your current pair of glasses simply call to book in to see one of our optometrist on 9728 7288.
