Optical under-screen fingerprint sensor and ultrasonic under-screen fingerprint sensor, which will be the mainstream in the future?

Nowadays, espcially in phone field, the two new technologies for under-screen fingerprints are becoming hot topic. One is optical under-screen fingerprint sensor and the other one is ultrasonic under-screen fingerprint sensors. We usually use fingerprint  under the optical screen. Now only few of Samsung models use ultrasonic fingerprint sensor under screen.  Which of the technologies has the advantages and disadvantages?

Then what is under screen fingerprint recognition?

Under-screen fingerprint recognition is widely used in today's mobile phone unlocking field. The screen emits light to illuminate the user's finger, and then the sensor below the screen receives the reflected light from the user's finger, recognizes and unlocks it; the light acts as a medium during the unlocking process. The ultrasonic fingerprint is just to replace the light module with ultrasonic.

The advantage of the fingerprint under the optical screen is that it is fast and not easy to break like the physic fingerprint sensor built in the phone main body.  Now the fingerprint recognition under the screen is very mature, and it can almost unlock in seconds, which is no different from the physical button fingerprint.

When you are about to unlock the phone, the fingerprint scanning area would light automatically, just a simple touch would unlock it.

When unlock under the ultrasonic fingerprint sensor, we cannot feel the existence of the ultrasonic wave, but the error rate of this unlocking method is relatively high, and the speed will be slower. But it wont be affected by water drops and mositure.

The fingerprint recognition under the ultrasonic is 3D information collection data, which is more secure than optical sensor, trust one day when the technology goes more mature and cheaper, it may be one day replace the optical fingerprint sensor.