Scientists have developed a camera that can see through the human body.
A beam of light from a slit-lamp microscope focused on a cataract.
Cataracts are the single biggest cause of blindness and are responsible for almost half of all cases worldwide. A new laser probe, originally developed for the U.S. space program, has been shown to detect the condition earlier than is otherwise possible. Its developers say that the technique can tell that a cataract is forming even when an eye looks perfectly clear.