Presbyopia has been frustrating people for thousands of years, causing sharpness of near objects to blur. As the eyes age, presbyopia worsens and that has inspired inventors throughout the ages to get creative for the ultimate fix.
Bifocal types have evolved, from the originals (celebrated by and even credited to Ben Franklin) all the way to trifocals, and most recently, progressive lenses and their variations.
You may know the story. Franklin and his contemporaries were tired of carrying around multiple pairs of specs, one for viewing far-away objects, and another pair for up-close purposes like reading, needlework and drafting the Declaration of Independence.
Up to Specs
The invention was a remarkable achievement, but neglected to address two problems: first, as presbyopia progresses, intermediate distance objects blur as well. So while the early bifocal types sharpen near and far objects, the most-used field of vision would still be blurry. Trifocals were invented to help this issue, but actually exacerbated the second problem.
The other problem that early bifocals had was the appearance of jumping images. That is, when the user shifts from viewing a far-away object to, say, his hands, the near object appears to jump up, as the brain scrambles to make sense of the newly-corrected focal length. If you've used traditional bifocals or trifocals, you know the disorienting sensation of experiencing this "image jump".
Enter progressive lenses, now the most popular lens choice for correcting presbyopia. Engineers have crafted a lens that does it all: sharpens images near, far and in between, without image jump or the huge size previously thought necessary to contain the multiple prescriptions. Progressive lenses smooth out the transitions between fields of vision so that your eyes can glide seamlessly from an approaching intersection, for example, to your speedometer, and then to your printed map. And the best part: your glasses no longer identify you as a 40- or 50-something.
Within the classification of "Progressive lenses", you have a number of options.
- Standard Progressive lenses are just that: Standard. They don't cost much more than traditional bifocal types, and they provide a wide reading area. The drawback is the size required to fit the vertical distance required for your eyes to travel between distance vision and reading. The result? Bigger lenses than you may have otherwise chosen.
- Next are Computer Progressive lenses, for the purpose - you guessed it - of working with computer-screen distanced objects. The sweet spot for clear vision with these lenses is between 16 inches away and 6 feet, perfect for a workday in the office. These cost about the same as Standard Progressive Lenses.
- Short Corridor Progressive lenses are for the fashion-forward consumer, who loves the fact that progressive lenses nix the tell-tale "bifocal line". This option will be about $100 more than standard progressive lenses, depending on the brand, short corridor progressive lenses offer that same seamless transition between distance vision and reading, but in a smaller frame.
- Premium Progressive Lenses are at least twice the price of Standard or Computer Progressive lenses, but that's because engineers and manufacturers have thought of - and eliminated - all issues attached to the other options. Known as "free form design", they offer a distortion-free reading area that extends farther both left and right.
Like most things, you have a few buying choices, and can opt for the option that "does the job," or the one that dazzles you. But unlike most things, your vision is vital to quality of life. Your doctor and our optical shop can help you decide which progressive lens is right for you.
For questions or comments, contact Woodhams Eye Clinic.