[THE INVESTOR] A fingerprint scanner integrated into a physical button on a smartphone will likely become a thing of the past as Samsung Electronics, the No. 1 smartphone maker in the world, is expected to have a fingerprint sensor built into the screen for its Galaxy S flagship lineup in 2019.

Samsung is preparing to adopt the biometric technology that allows users to scan their fingerprints on the screen for all three variants of the 10th edition of the Galaxy S, according to an industry source Tuesday.

Previous reports had claimed that Samsung would use in-screen fingerprint sensors only for the two high-end Galaxy S models, while the lower-end variant would feature a physical button fitted with a fingerprint sensor on the right side.

“The two high-end Galaxy S models will come fitted with an ultrasonic in-screen fingerprint scanner while the other one will house an optical fingerprint sensor beneath the screen,” an official from the display industry told The Investor. The official launch is expected to take place in February, and the phones will likely hit stores in March.

The ultrasonic fingerprint sensor for the S10 lineup will be exclusively supplied by US chipmaker Qualcomm, which first announced the technology in 2015.

The ultrasonic fingerprint technology creates a 3D mapped fingerprint instead of a flat image used by optical and capacitive scanners -- two of the most-used fingerprint scanner types utilized in smartphones.

The ultrasonic scanner boasts more accuracy than traditional ones, as it is not affected by grease, sweat, or light.

An optical sensor, which is three times cheaper than the ultrasound sensor, works like a digital camera, capturing a two-dimensional image of a fingerprint. It is considered relatively easy to spoof as it makes use of a 2D image to authenticate users, and its accuracy rate tends to decrease if the finger being scanned is dirty, too wet or dry and external light gets in the way.

The disadvantages, however, do not mean the optical scanner is too immature to be in place as it works great most of the time, the source said. Samsung and Apple have been using the optical fingerprint scanning technology for their respective flagship models.

The Korean tech giant planned to implement optical in-screen fingerprint sensors developed by Synaptics for its Galaxy S8 in 2017, but the optical scanning technology in the screen was far from perfect at the time.

Despite technical immaturity, some Chinese smartphone makers, including Huawei and Vivo, have rolled out smartphones installed with fingerprint readers that enable users to authenticate by pressing on the screen.

“For market leaders like Samsung and Apple, it is too risky to deploy a technology that is not ready for implementation since the technical immaturity could hurt their brand image,” an industry watcher said.

Analysts forecast the in-screen fingerprint scanner could trigger changes in the overall smartphone market in 2019.

“In-screen fingerprint scanning will take center stage in the smartphone market in 2019,” said Lee Dong-joo, an analyst from KTB Investment & Securities, in his previous investment report, adding most major fingerprint sensor makers are working with Samsung Display, a dominant player in the smartphone OLED display market, to incorporate biometric sensors in organic light-emitting diode displays.

Lee also said deployment of the scanning technology would bring extra value to the self-emissive display, which is currently used for top-tier smartphones, driving up the prices of OLED screens as well as high-end smartphones.

Market research firm IHS Markit forecast shipments of smartphones featuring in-screen fingerprint sensors would hit 100 million units next year.

By Kim Young-won (wone0102@heraldcorp.com)