One of the biggest challenges faced by the blind and partially sighted is navigation – finding one’s way around, inside and outside the home.
A colleague who kindly looks out for items I might be interested in recently sent a link to an article about two new navigational devices for the blind that are under development in different African countries. There are similar systems being developed elsewhere.
These are high-tech solutions though, and costly. One uses three-dimensional sensors – I am not sure what is meant here – and the other ultrasound. They are expensive – the cost is estimated at being “as little as” $150.
I think that’s a lot, especially when compared with the traditional low-tech white cane, which can be made at minimal cost, works very effectively for many people, and is quite intuitive to use.
All this got me pondering about the commonest form of visual assistance – glasses. Although refractive error – lack of clear visual focus – is not always regarded as visual impairment, without glasses or other refractive correction such as contact lenses it certainly becomes so and is classified as such by the World Health Organisation.
This brought me on to wondering where and where glasses were invented. At the time they must have been high-tech, so was their cost within the reach of most people? Surprisingly the answer seems to be yes. I think they must have been more affordable than $150 would be to the majority of people in the world.
The precise history of spectacles, like many technologies, is hard to pin down. However Italy is probably the country where glasses in the modern sense were invented (although people may have used various ad hoc forms of focus correction in earlier times). A sermon given in 1305 by Fr. Giordano in Florence convincingly refers to the invention of spectacles as being within the previous 20 years.
And how much did these new spectacle cost? Here I owe my information to a fascinating discussion on Reddit.
In 1384 there’s a record of 1151 pairs of glasses being imported into England. Then as now the lenses were the smaller part of the cost. You could go from leather frames at only 1 d (one old Engish penny) right up to ones made of horn (horn-rimmed has always been a popular style) at 9 ½ d.
According to the Reddit discussion the going wage at the time for someone who worked thatching roofs was about 6 d a day. So in England at that time glasses cost a bit more relative to today, but it wasn’t in a different league.
But moving forward rapidly to the present day we find there are many people in the world who need glasses but cannot afford them, or cannot get the ones they need.
Vision Aid Overseas has a website which listing some shocking facts. Websites that try to raise our awareness naturally try to be hard-hitting, but I’ve extracted just three bullets that I felt illustrate the scale of the disadvantage.
- 10% of the people in the world need glasses they can’t get
- 500 million older people can’t do tasks that involve close vision
- 45 million people of working age risk loss of livelihood because of correctable vision loss
I knew dimly that glasses people no longer require are collected for recycling, but I didn’t have any proper idea of how much this matters.
Over the years I have accumulated a small drawer full of reading glasses I no longer need. I shall donate them as soon as possible. I’m very glad I didn’t just throw them away.