理由是：当你在玩手持游戏的时候，你将不会再显示屏前移来移去的，而是相对比较容易固定在观看3D效果的最佳位置上。

The reason: When you play a handheld game, you are less likely significantly shift your position in relation to the screen, making it easier to stay in the viewing sweet spot.

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在显示屏作平面图形搜索场景，头部固定的试验条件下，绝大多数扫视幅度不大于8度。

The author also found that, in a screen display search scene and fixed-head condition, most saccade sizes are seldom larger that 8 degrees.

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另外，LED点阵屏尺寸多为整块固定的，不能根据需要进行调整。

In addition, most of the LED lattice screen is fixed in dimension and cannot be adjusted according to need.

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