iPhone 5S may sport sapphire crystal capacitive Home button with fingerprint sensor

The Home button has got to be one of the defining features of the iPhone’s clean rounded rectangular design. Whereas some other manufacturers add a bunch of physical buttons to their gadgets, Apple instead has moved all controls to the iOS software, leaving only the Home button on the iPhone’s face.

That could change with the iPhone 5S, the next iPhone refresh expected later this year. If a new rumor is to be believed, Apple will for the first time replace the iPhone’s Home button – prone to failure after long periods of use – with its capacitive counterpart.

This isn’t new: many Android handsets have touch-enabled “buttons” like Samsung’s Galaxy S series, for example. Apple’s innovation, the story goes, involves using sapphire crystal to prevent scratches and dings and protect the integrated fingerprint sensor…

Taiwanese publication TechNews Tuesday (via Cult of Mac) quoted Apple supply chain sources who are adamant that Apple has opted to use sapphire crystal for the Home button on the iPhone 5S.

Analysts think fingerprint scanning is one of the killer features of the iPhone 5S. Just yesterday, PayPal said it expected the next iPhone to kill passwords once and for all by focusing on a more reliable and stronger fingerprint-based authentication method.

Replacing the current Home button with a non-moving counterpart wouldn’t be out of character for Apple. Remember, the company replaced the original iPod’s mechanical click wheel with a touch-sensitive variant on the second-generation model.

Notably, Apple currently uses sapphire crystal to protect the iPhone 5′s back camera lens from scratches.

Sapphire crystal has a hardness second only to diamond and is used because of its compatibility with optic sensors, Apple explains on the iPhone 5 web page:

Although the surface of the iSight camera is as clear as glass, it’s not made of glass. It’s actually sapphire crystal, whose hardness is second only to diamond on the scale of transparent materials. That means the surface of the lens is far less likely to scratch.

The rumor actually makes a whole lot of sense.

If Apple is to integrate fingerprint sensor right underneath the Home button, as rumored, while at the same time move to a capacitive touch-enabled Home button variant, protecting the whole sensitive assembly from physical damage would be prudent.