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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"That is the case today. And it is the first time any president has acted outside the June 1 time frame,".

VOA: standard.2009.04.15

The frame lines frame precisely the shot the photographer envisages, while allowing a clear view of the scene outside the viewfinder frame.

ENGADGET: Leica M9-P looks like it costs a fortune, doesn't disappoint

If anything, their confidence was bolstered once they had a chance to examine the drawing outside the dusty old frame, and found a small signature hidden under a mount.

FORBES: The Ultimate In Reality TV? Try Televised Art Forgery. [Book Excerpt #2]

But the most powerful light seems to come, appropriately and mysteriously, from outside the picture's frame, above and to the right of the window.

WSJ: The Calling of St. Matthew | A Dramatic Enlightenment | Masterpiece by Willard Spiegelman