What is TouchID?
In simple words, “TouchID is fingerprint identity sensor functionality that will allow a user to open a iPhone by identify their fingerprint”.
That means now you need not to remember your password to unlock your iPhone. Your fingerprint will act as an identity proof for you.
How TouchID works?
Apple is smart enough as they have implemented this TouchID functionality on most used home button. It is not easy to fit a perfect fingerprint sensor system in such a small place.
In iPhone 5S they have created the home button from laser-cut sapphire crystal. Fingerprint identity sensor system works as below.
1- User put its finger on home button.
2- The surface of the button directs the image of user’s finger to a capacitive touch sensor, which reads beneath the outer layers of your skin to get a detailed print.
3- Surrounding the home button there is a stainless steel ring that detects the user’s finger, wakes the sensor, and improves the signal-to-noise ratio.
4- Finally software reads the ridges of print and if it finds the perfect matching fingerprint in the system then it’s unlock your phone.
You have to store your fingerprint sample while configuring your iPhone first time.
Architecture of fingerprint identity sensor
It has four basic components
1- Laser cut sapphire crystal (your home button made of it)
2- Stainless steel detection ring (it detect your finger and start the sensor)
3- Capacitive single touch sensor
4- Tactile switch
Benefit and Key features of TouchID
1- You need not to enter your password while making a purchase from iTunes Store, The App Store or iBook Store. Your TouchID will approve all your purchase.
2- Touch ID is has 360-degree readability feature; which means no matter what its orientation — portrait, landscape, or anything in between — your iPhone reads your fingerprint and detect your identity.
3- You can store separate fingerprint sample for each user.