The display self-adjusts to become an ultra-high contrast e-book reader in bright sunlight, and a bright full-color backlit display in normal light.

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It works like bifocals in that you look up to see the display so your normal vision below is never blocked.

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And unlike the bulky Pulse with its ostentatious display, they are practically indistinguishable from normal pens and both come with software that can do a decent job of converting handwriting to text.

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Switching involves looking at an element of the screen and giving a big blink to select -- the display seems adjusted in such a way that normal blinks won't trigger it, so you're less likely to accidentally set something off.

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And, although the downtown installation has an old-fashioned aura that couldn't be further from the sophisticated Park Avenue display, both projects alter the spectator's normal perspective on a well-known neighborhood.

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But in the course of normal business activities, neutral cultures are more careful to monitor the amount of emotion they display.

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At 220 pixels-per-inch, the Retina display's pixel density is so high the human eye cannot distinguish individual pixels from a normal viewing distance, so text and graphics look incredibly sharp.

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