A camera at the bottom of the lens tracks the viewers by collecting light coming the other way through the lens and the Angle of the LEDs changes to correspond to the viewers' movements.

透镜底部的摄像头通过收集反射回来的光线定位观众的位置，同时发光二极管的角度根据观众的移动发生改变。

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Light enters at the thinner, bottom end of the lens and bounces around until reaching the desired Angle and emerging from the front of the lens.

光线在确定合适角度以后，经透镜底部较薄处折射后从透镜前端发出。

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Humans are wired to calculate the distance of an object by using the vertical Angle between its top and bottom.

人类通常是通过一个物体上下间的的垂直角度来计算与它相隔的距离。

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And instead of a drag on the bottom line, Roomba has subsidized the development of what Angle hopes is the next big step for iRobot: health care.

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There's not much good to say about the built-in "tilt stand" at the bottom, either -- it only alters the angle of projection slightly and feels too plasticky -- but at least it gives you an extra option.

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The center of the screen shows video from the landing and graphics at the bottom show the lunar model's angle.

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