Razer DiamondBack

@ 2004/12/24
In order to maintain the highest possible motion accuracy, the mouse must gather as much information as it can while it is moving, which is achieved using a special image processing engine, that provides a scan resolution of up to 1600dpi. Such resolution allows the mouse to scan a square inch with the highest level of accuracy (in comparison with the other products in the market), so even the slightest movement will receive a reaction on the screen, and be much smoother than ever before. The image that is scanned by the optical sensor is analyzed by the microprocessor and translated into the cursor's motion on the axis system.

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Comment from jort @ 2004/12/24
i've got that mouspad too