Irritating though this may seem, it's a simple reflection of the fact that there is no one ideal design for all software.

这看起来可能很令人恼火，但它反映了一个简单的事实：没有任何一种设计可以理想到适用于任何软件。

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It's sweet and simple: the camera captures the reflection of light on the user's eye, and image processing technology then calculates the user's viewing angle to allow for hands-free navigation on-screen.

ENGADGET: Fujitsu eye-tracking tech uses built-in motion sensor, infrared LED for hands-free computing (video)