Till now we have heard a lot about iPhone 8 new technology shift, but fewer know how it works. Although technology shift is not new in tech world but real question arises about changes and working. Apples’ OLED screen is one such example. We can say that it’s a game changer not only for battery life but for related technologies.
Since iPhone 5s, Apple has gained huge success with best in build finger print reader, unless it is moved back to the phone. This technology is need to be changed. Touch ID is developed by AuthenTec, it senses the presence of finger with a detection ring which switches on the sensor when it detects a digit. The sensor itself is clad in a thin sapphire crystal, and uses a complementary metal oxide semiconductor capacitive touch sensor to detect the fingerprint’s whorls and ridges with 500 pixels per inch resolution.
The captured fingerprint is then passed to the Secure Enclave and compared to stored data local to the phone. Should the mathematical models match, the phone is unlocked. There are two major revisions of Touch ID, with the only real difference being sensing speed in more recent version on the iPhone 6 and iPhone 7 families.
The problem is difference between the thickness of sapphire lenses and sensor. Sapphire lenses is not that much thicker whereas, the sensor thickness is 170 macrons. While an OLED screen assembly is thinner than that of a comparative LCD display, the glass cover is about the same thickness between the technologies. At just less than 1 millimeter thick, the screen glass is over five times the thickness of the sapphire lens on the existing Touch ID sensor on the iPhone 7.
With fingerprint sensors used in Touch ID, as separation between the contact surface where a user places their finger and the capacitive sensing array increases, there is a corresponding blurring of the finger’s electric field captured by the Touch ID sensor. In the existing Touch ID implementation, the lens is sufficiently thin that any distortion, or aberration, is minimal.
When a sensor is placed behind a thicker lens, in the case of the “iPhone 8,” behind the screen glass itself, the inevitable blurring without some form of correction can lead to degraded fingerprint image resolutions and decreased recognition accuracy.
There are reports suggesting that Touch ID is what may hold up the shipment of the “iPhone 8,” but not the reveal. There are more claiming that the sensor may get relocated to the back of the device, but given the flak that the Samsung Galaxy S8 is taking for having done so, that may not be the case either.
The road to Touch ID and a virtual home button under a front screen glass was paved with the solid state button on the iPhone 7 . The technology is crucial to Apple’s services, as it is a key underpinning of Apple Pay to say nothing of crypto logical protection of a user’s data living on the phone.
Cook and company don’t ship a product until they feel that what they’ve developed is the best that they can make it, for the widest user base, and as safe as possible. However Touch ID develops on the “iPhone 8” in the next few months for the final shipping version will not deviate from that, perhaps at the expense of not shipping in 2017 at all.