Tech giant Google has said it has developed a prototype contact lense that could make it easier for 350 million diabetics worldwide to monitor their blood sugar levels. The prototype monitors blood sugar levels once every second and the results can be sent wirelessly to a smartphone where alerts tell the person if action is needed. The developers are also considering building tiny lights into the lens, which would also alert the wearer. But Google is not the first company to attempt to develop a so-called smart contact lens. Al Jazeera's Tarek Bazley explains.
