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A reflective prism device demonstration unit built with double-sided mirror segments mounted on a dark surface. (A) A photo from the side showing the real target (wooden ruler) marked by a white ellipse. The user’s direction of view is shown by the thin white arrow drawn on the dark surface from left to right. (B) An image of the target is seen in the reflective prismatic device in the direction of the thick white arrow; it is shifted by 36 degrees (∼73Δ).
