That hasn't stopped it from filing yet another one though, as the latest application reveals a fingerprint sensor apparently embedded into the iPhone itself.

ENGADGET: Apple files patent application for fingerprint sensor that can be transparent or opaque

As with a fingerprint sensor, you'll be required to recreate the same hand motions several times as a way of setting up a user profile.

ENGADGET

Rather than using a passcode or swipe pattern to unlock the phone's screen, the new handset's fingerprint sensor allows users to simply press and slide a finger across a switch to quickly unlock it.

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Of course, take any of these patent applications with a generous pinch of salt -- we haven't seen an Apple stylus yet, for example -- but perhaps this is the reason Apple bought fingerprint sensor maker AuthenTec back in July.

ENGADGET: Apple files patent application for fingerprint sensor that can be transparent or opaque

While AuthenTec is known best for its fingerprint-sensor chips, it also has a number of security products.

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Art Stewart, vice president of wireless products at sensor maker AuthenTec, which provided fingerprint sensors for the phone, says LG had "antenna issues" with the device.

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According to the filing, the biometric sensor in question might indeed be a fingerprint reader.

ENGADGET: Apple files patent application for fingerprint sensor that can be transparent or opaque

When the sensor's cap had ridges, like a fingerprint, it was able to amplify and filter certain vibrational frequencies, the authors said.

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