The 9 most impressive social good innovations from October

Solving the world's biggest problems requires creativity and perseverance -- and innovators around the globe are taking up the challenge. From a device that alerts medical workers when to re-bandage a wound to a wheelchair specifically designed for people in developing nations, these inventions are making a massive difference for those who need it most. While certainly not an exhaustive list, here are nine ingenious innovations that made an impact in October. An estimated 2.3 billion people worldwide live with poor vision due to refractive errors, with many living in low-income regions without access to regular health care. The Folding Phoropter, a cost-effective eye-screening tool, hopes to make essential eye health more accessible to these populations.