But Wall Street valued Sony incorrectly for the same reason that Sony continued to misunderstand its own value: In 2000, Wall Street and Sony both believed that Sony was a device maker and that ever-improving devices would rule the world.

BBC: Viewpoint: How Sony slipped back

The new rule will allow screeners to focus on finding explosive device components and other things that can be "catastrophic" to a plane, speed trips through security checkpoints and "address the hassle factor, " Pistole said.

CNN: March 7, 2013 -- Updated 0312 GMT (1112 HKT)

Some eye-care offices have a device called an accommodation rule that allows a technician to slide an eye chart back and forth to simulate different distances.

WSJ: How Technology Tries Our Eyesight