Entry tags:
Emergency spectacles
This is fun, and it works - I just tried it. (the practical value may be limited, but I can actually read text that I can't otherwise read without my glasses)
A good one if you ever want to show the kids some instant science.
A good one if you ever want to show the kids some instant science.
no subject
And the pinhole sunglasses were one of the things I think Tomorrow's World mentioned years ago as eye trainers as they allowed you to see but also encouraged your eye muscles to work to help keep them healthy and better able to focus on things (though those of us with astigmatism need more than strong eye muscles!)
http://www.jdharris.co.uk/product_info.php?pName=pinhole-glasses