From left to right, Zongfu Yu, Ang Chen and Efram Khoram developed the concept for a "smart" piece of glass that recognizes images without any external power or circuits. The sophisticated technology that powers face recognition in many modern smartphones someday could receive a high-tech upgrade that sounds -- and looks -- surprisingly low-tech. This window to the future is none other than a piece of glass. University of Wisconsin–Madison engineers have devised a method to create pieces of "smart" glass that can recognize images without requiring any sensors or circuits or power sources. "We're using optics to condense the normal setup of cameras, sensors and deep neural networks into a single piece of thin glass," says UW-Madison electrical and computer engineering professor Zongfu Yu.

Earlier this week, Apple unveiled its new flagship smartphone, the iPhone X. Its marquis feature is a front-facing array of sensors it calls the TrueDepth camera, designed to recognize and track a user's face. It replaces the fingerprint scanner as the biometric method for unlocking the phone. The iPhone X isn't the first device to include this feature. Windows Hello (which is mainly for laptops and tablets), and the Samsung Galaxy S8 also incorporate a facial recognition login, though the latter is based around an iris scanner rather than a whole face match. But Apple has especially made the security of its iPhone a critical aspect of its marketing, refusing in 2016 to unlock the San Bernardino gunman's iPhone.

Apple's recently revealed feature, the Face ID, which scans a user's face to unlock its iPhone X device has raised privacy concerns -- Sen. Al Franken (D-Minnesota) called on the company's CEO, Tim Cook to address these concerns in an open letter Thursday. Franken believes biometric data that Apple is accessing, needs to be guarded by privacy and security guidelines. Apple will actually store a face print -- a scan of your face to match up with the biometric lock on your phone. Franken has raised concerns about the use of these face prints. "To benefit other sectors of its business, sell it to third parties for surveillance purposes, or receive law enforcement requests to access it facial recognition system -- eventual uses that may not be contemplated by Apple customers," the lawmaker said in an open letter to Cook. Face ID uses a dot projector, infrared technology, and a flood illuminator along with a bionic A11 chipset to create a depth map and image data of a user's face.