Someone has put up a post on imgur claiming to demonstrate unlocking a Galaxy S10 by 3d printing a fingerprint based on an image of the fingerprint,
First I simply took a photograph of my fingerprint on the side of a wine glass. I used my smartphone to take this picture, but it’s certainly not out of the question to use a long focal length DSLR camera to snag a fingerprint image from across a room…or further.
I then pulled the image into Photoshop and increased the contrast, and created an alpha mask.
I exported that over to 3ds Max and created a geometry displacement from the Photoshop image which gave me a raised 3d model of every last detail of the fingerprint.
I popped that model into the 3D printing software and began to print it. This was printed using an AnyCubic Photon LCD resin printer, which is accurate down to about 10 microns (in Z height, 45 microns in x/y), which is more than enough detail to capture all of the ridges in a fingerprint.
As the author of the post notes, if a smartphone is stolen, it is likely that a fingerprint of the owner will be found on the phone itself (especially if the user is repeatedly touching a specific area of the screen to unlock it, as someone using the ultrasonic fingerprint reader would be doing).