Circular screen: a glass halftone screen having a circular outside frame, to permit screen rotation, for convenient screen Angle selection.

圆网屏：是玻璃制的半色调网屏。它有着可以旋转的圆形外框，方便调换网线角度。

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For the method, the threshold value matrix of a second screen with a different screen Angle and width is read out and compared with the color values of a halftone image presented.

对于该方法，将具有不同加网角度和加网线数的第二网屏的阈值矩阵读出并且与所提供的半色调图像的色值比较。

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