Self-Adjusting Eyeglasses

"Self-Adjusting Glasses Ready for Distribution to Developing Nations"



"...[E]ach lens in a pair of Eyejusters actually contains two lenses. Turning a dial on one of the temple arms causes the lenses to slide across each other, changing the overall spherical surface and thus changing the prescription. It works for those with myopia or presbyopia, and the glasses can be adjusted by the users themselves or anyone with very basic training."  

Update: Some adjustable liquid-based eyeglasses.