Eye contact ties the speaker to the masses with an invisible tether and forces them to pay attention.

眼神的交流能使谈话者的注意力无形之中集中起来。

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Imagine the shell of your tablet, smartphone or laptop also serving as an essentially invisible speaker.

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Move further up and you'll encounter the 12-megapixel camera, flash and nearly invisible speaker grill.

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The membrane is made from optically clear material that allows for totally new, invisible speaker designs.

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