Here's one major feature that the iPhone 8 will be missing

Just like Samsung, Apple was unable to get the technology perfected in time before its 2017 flagship.

Also Read: A revamped feature by Apple in iPhone 8 could make a lot of people unhappy

After failing to integrate the on-screen fingerprint sensor, Apple doubled up its facial ID recognition system and dropped Touch ID entirely.

A leaked look of Apple's upcoming iPhone 8 (Courtesy: @MacRumors on Twitter)

US Patent no 9,747,488, titled as “active sensing element for acoustic imaging systems,” apparently describes the method of reading a fingerprint for authentication through ultrasonic detection.

How will Apple's new fingerprint sensor work

The acoustic system sends out a pulse which can pass through a second layer (“substrate”) and this in turn is reflected back to the piezoelectric transducers which determine the image of whatever object is touching the substrate.

The ridges and valleys of the fingerprint create acoustic boundaries that will now allow them to be told apart.

Also Read: Apple drops a clue, iPhone 8 to sport bezel-less screen and facial recognition

The patent also mentions how Apple intends to regulate the technology that will need high voltages. For this purpose, Apple's technology will control the drive signal, voltage bias and ground reference for each unit, for its “active sensor”.

iPhone enthusiasts can expect Apple's on-screen fingerprint reader to roll out with Samsung’s upcoming Galaxy s9 or Note 9 in 2018, or Apple’s next year iPhone upgrade, a Plus model of which is expected to carry a display of 6.46-inches.