CBInsights reported the patent in question would be for a system that would use a smartphone or laptop’s front-facing camera to take brief photos of you while you’re using Facebook. According to the patent, Facebook could then use these temporary photos to determine your emotions when seeing various types of posts on the News Feed. With this information, the social media network could then provide content tailored to keep you on the service for longer.
http://www.ibtimes.com/faceboo