R&D Director, Fredrik Clementson explains the difference between in and under display fingerprint sensing, watch video:
New mobile design with slick and user-friendly edge-to-edge displays is paving way for new sensor technologies. Ultrasound and optical fingerprint sensors that can read through display, glass or even metal and plastic is being introduced into devices to further improve the convenience and security of identity authentication.
Let’s start with clarifying the difference between a fingerprint sensor placed in or under the display. The first smartphones and concept devices with fingerprint sensors integrated under display or glass, as in illustration 1 and 2, have been introduced on the market this year. For example, Huawei recently launched Honor 10 with an ultrasound sensor under glass and earlier this year Vivo launched its X20 Plus where the fingerprint sensor is placed under the display. These types of solutions provide greater user experience and lower production costs as they can be used for new smartphone designs with edge-to-edge displays, but also placed on the backside of devices, without cut-outs for a sensor.
We are heading towards solutions with sensors fully integrated in the display, as in illustration 3. This is what we can expect to see in 2-3 years, according to industry analysts like Jamie Fox at IHS Markit. The development of in-display solutions is driven by the mobile industry’s desire for more efficient production process, along with improving user convenience and security.
There is an apparent convenience win in placing the finger anywhere on a mobile screen, instead of having to use a thumbnail sized button or hot zone, which is supported by in-display solutions. In-display sensors covering most or the whole screen, furthermore will provide larger images thus enabling better biometric performance and allow simultaneous authentication using two or more fingers. This creates the possibility to add an extra layer of security, which can be used when you’re, for instance, opening a sensitive mobile application or making a payment.
Also, since we use our mobile device several times a day, a larger sensor solution could support frictionless continuous authentication*. This is desirable when the mobile is becoming a device for personal identification, where we do all our personal affairs: from banking transactions to accessing sensitive documents.
A person’s behavior enables a continuous verification of identity throughout a session. By using a mobile device with an in-display sensor that can recognize fingerprints in most of or the entire display, the user is able to be continuously authenticated.