Most of the fingerprint sensors in the smartphones are now placed under home button. These ‘button type’ modules required you to press a finger on a raised square or circular button for your fingerprint to be read exactly, so the sensor was usually mounted on the front, rear or side buttons of a smartphone.
Today, LG Innotek announced an under glass fingerprint sensor module which will let you just place your finger on the cover glass of the phone and then it identifies your fingerprint. This new module will allow smartphone designers to avoid the home button itself.
LG cut a shallow furrow of 0.01inches (0.3mm) thick on the lower backside of the cover glass and installed the fingerprint sensor inside of it with using their supreme precision and combination technology. Since the sensor is placed behind the glass, OEMs can produce a sleek designed smartphone. Since high-strength cover glass like Gorilla Glass protects the sensor, it also prevents it from coming in direct contact with water or damage from scratches. Most importantly, the fingerprint accuracy of this new module is almost same as the button type with a false acceptance rate (FAR) of 0.002%.
LG developed a proprietary adhesive to be used to attach the sensor to the glass and the adherent side of the sensor and glass is only 0.0098inches (0.25mm) thick, but it endures impact of 4.6 oz (130 grams) of the steel ball dropped from 7.9inch (20cm).
The latest Lumia flagships comes with “biometric authentication” support which allows you to sign in with your face. Even though it works most of the time, having a fingerprint sensor under smartphone cover glass would be the most convenient way to authenticate.