It is also shown that only when the gratings are cylinder or plane ones, the second order sagittal anastigmatic circular field and meridional non defocus flat field spectral images can be formed.

还指出仅当柱面或平面光栅时，才能形成二阶子午无离焦平场和弧矢无象散圆场谱面。

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Many of the semi-finalists' redesigns are as simple as adding multitouch gestures or bending the traditionally square playing field into a more circular court, but a few ambitious developers mixed it up with 3D playing fields, anthropomorphic paddles or augmented reality multiplayer.

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"We've had our field services team out on the 5km of right of way, the circular route, clearing trees to get it all open, " he said.

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