Note 9 won't have in-display finger scanner, but the Galaxy S10 might
The Note 9's finger scanner could still look like this
It turns out that, while there is already a phone with in-display scanner, the Vivo X20 Plus UD, and it does come with OLED display, Samsung's efforts in the field had to deal with its current curved Infinity Display design, which has been challenging, to say the least. If an optical reader of this type was embedded under the display, it had issues with the OLED display's semi-transparency, and hence reliability. A more orthodox capacitive type reader, on the other side, could be made relatively transparent, but has to be mounted on top of the display, which presented issues with durability.
Finally, an ultrasonic finger scanner could be the Holy Grail of the in-display types, but that technology is still in its nascence to land in the Note 9, which will enter mass production in June, tip insiders. By nascence we mean that it's still very expensive, challenging to produce in mass quantities, and is slower than a rear-mounted scanner would be. Still, there is some progress, it seems, as Samsung has limited its large amount of initial in-display finger scanner suppliers to just a few, and is devoted to working with them on R&D efforts.
"There are advantages and disadvantages of both optical and capacitive or ultrasonic types, so I do not think there is any technology that can be commercialized right now," tipped one industry insider. "Next year, Samsung Electronics I think will succeed to mount it."
source: The Bell (translated)
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