Are you over age 40 and unhappy with your current glasses for presbyopia correction?

Most people who need prescription lenses for nearsightedness, farsightedness and/or astigmatism attain clear, comfortable vision at all distances with progressive lenses when they become presbyopic. But some are frustrated by the relatively limited field of view these and other multifocal lenses (bifocals and trifocals) provide for intermediate and near vision.

And people who have clear distance vision without glasses and need only reading glasses when presbyopia occurs have problems, too. They often are frustrated by forgetting to bring their reading glasses with them or are constantly needing to put them on and take them off to see clearly at different distances.

If you're in either of these groups, here's some good news: multifocal eyeglasses are now available that can solve these problems and give you clear, unobstructed vision at any distance...with just a simple turn of a dial inside the eyeglass frame.

These potentially game-changing glasses for presbyopes are called adjustable focus glasses (also called adjustable focus reading glasses and variable focus eyeglasses).

Adlens

Adlens adjustable glasses are an exclusive frame and lens combination with a compound lens system that enables the wearer to focus on objects at any distance.

Called Alvarez Dual Lens technology, this lens system features two thin, wave-shaped polycarbonate "plates" that slide across each other by means of a small knob on the frame. The position of the two plates relative to each other determines the power of the overall lens system.

Adlens adjustable eyeglasses are designed for use as a temporary or spare pair of glasses, and the power of the lenses can be customized instantly to correct from -6 diopters (D) of nearsightedness to +3 D of farsightedness with the simple turn of a dial. They also can be adjusted for special visual needs, including reading and computer use, or used to manage fluctuating vision for people with poorly controlled diabetes or after eye surgery.

In addition to selling adjustable focus eyeglasses to consumers online and via select retailers, Adlens has established philanthropic programs to bring vision correction to the developing world, particularly in areas where little or no affordable eye care currently is available.

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Eyejusters

Eyejusters is another major manufacturer and marketer of adjustable focus glasses.

The UK-based company specializes in adjustable focus reading glasses that enable the wearer to dial the proper amount of magnification for seeing objects from arm's length to very close-up.

Eyejusters launched their line of adjustable focus reading glasses in 2016, describing the eyewear as, "a single pair of glasses to replace all your reading glasses."

The company points out that a single pair of reading glasses cannot be optimum for all the different activities people with presbyopia are faced with every day — including reading, checking texts on our phones, hobby work, using electronic tablets and viewing computer screens — because all these devices and objects are at different distances from our eyes.

Eyejusters adjustable focus reading glasses overcome this problem with two small, hidden adjustment dials (one for each eye) on the inside of the hinge of the eyewear frame. By turning these dials, the wearer can adjust the power of the lenses to be perfect for any reading distance.

The two separate adjustment dials allow even people with different-powered eyes (one eye a little more nearsightedness than the other, for example) to attain the proper, balanced focusing power they need for the task at hand, according to the company.

Each lens of the latest generation of Eyejusters can be adjusted from a power of +0.50 to +4.00 diopters (D) for a wide range of near vision tasks.

Eyejusters adjustable reading glasses are available in a variety of frame designs, colors and materials and the eyewear can be purchased on the company's website.

Like Adlens, in addition to marketing adjustable focus eyeglasses to the general public, Eyejusters manufactures and distributes self-adjusting eyeglasses to combat preventable vision impairment from presbyopia and uncorrected refractive errors in the developing world.

Adjustable Focus Glasses — Humanitarian Efforts

Much of the philanthropic work to correct preventable vision impairment being done by Adlens and Eyejusters in disadvantaged areas of the world has been inspired by an organization called the Centre for Vision in the Developing World. (CVDW).

The stated mission of CVDW is "to help people in the developing world to see clearly, thus improving their quality of life and economic potential."

Adspecs self-adjustable eyeglasses. (Image: Centre for Vision in the Developing World)

The adjustable glasses developed by CVDW are called Adspecs adaptive spectacles.

To change the power of Adspecs adjustable lenses, the wearer turns a wheel on syringes temporarily attached to the sides of the frame. This pumps more or less silicone oil into a chamber formed by two flexible lens membranes that are protected by a rigid outer lens made of plastic. Once the lenses are adjusted for the best vision possible, the user tightens the screws on each side of the frame and removes the syringes.

Adspecs adjustable glasses can correct nearsightedness, farsightedness and presbyopia (but not astigmatism).

More than 100,000 people in 30 countries now wear Adspecs adjustable glasses distributed by CVDW and other humanitarian organizations.

You can learn more about the Centre for Vision in the Developing World and donate to the organization at the CVDW.