Medical Mirror : While it can't tell you if you're the fairest of them all, the Medical Mirror can tell you your heart rate, which is probably more valuable in the long run anyway. A webcam behind the mirror captures variations in reflected light on your face, and an algorithm translates that into heartbeats. MIT PhD student Ming-Zher Poh is the inventor of the medical mirror. How does the technology work? It uses light to measure the information from your body. Every time your heart beats, the blood in your vessels increases very slightly. Blood absorbs light and so this increase absorbs more mono light, decreasing the amount of light being transmitted or reflected by your body. Using optical methods for measuring the flow of blood is not new. You may be familiar with a little clip called a pulse oximeter that the doctor puts on your finger to take your pulse by shining an infrared light under your skin. Our approach is similar but in this case we're not shining light at you, we're just using the ambient light around you: sunlight, room light or anything that's illuminating your environment. The camera then measures the mono light being reflected off you, in this case, your face. Source :MIT Media Lab Medical Mirror - YouTube
