Self-adjustable glasses

Eyejusters

Spectacles designed for use in developing countries, where people do not have access to the glasses they need. These glasses are self-adjustable, using a technology called Slidelens - a revolutionary technology that works by sliding the lenses over each other.

Features:

• READJUSTABLE : The lens power can be changed at any time, allowing the glasses to be fine-tuned or even shared.

• FRAME FOR ALL : The frame is designed to fit on many faces. Moreover, they come in various colours to meet user's tastes.

• POWER RANGE : The lenses provide power from -5D to +4.5D, covering most of the people.

• CUSTOM BUILT TECHNOLOGY : The Slidelens technology is innovative and provides a quality optical experience at low cost.

A video on how to use eyejusters:

Purpose:

 

 

 

How they work:

Try this demo

Basically there are two lenses of a unique shape. When they slide over each other, they act like a single lens with a changing spherical surface.

The power of the SlideLens goes up as you move across it - so you have one side that has a negative power and the other side has a positive power.

Left diagram : Power throughout the regular lens is constant.
Right diagram : Power goes up along the lens as you move across it.

 So, if you take the lens, turn it over, and put the two Slidelens elements together, you get a normal lens, as illustrated in the following diagram:

Both Slidelens elements combine to form a normal lens.

Now, try guessing what happens if you slide one lens over the other?

The power changes!

Power changes as you slide one lens over the other.

However, life isn't all that simple.

Aberrations, distortions and problems in peripheral vision can give you a headache.

So we went back to the optical calculations and did clever stuff. By custom-designing the lens surfaces using state-of-the-art in-house software, we've been able to reduce the aberrations and distortions, make the lenses as thin as possible and extend the power range so that as many people as possible can use SlideLenses to correct their vision.

 Further reading