Abstract: A device for indicating a definite direction, comprising a screen located in front and a screen located behind, which comprise opaque lines (3) separated by transparent interstices (4), whereby a moire pattern arises when the device is viewed. The screens (8,9) have different division. The opaque lines (3) have the same width in both screens (8,9).According to the invention the device is characterized in that one of the screens (9) is provided with only one opaque line less than the other of the screens (8), that in said one screen the width of a transparent interstice plus the width of an opaque line (3) is greater than or about equal to 1.5 times the width of the opaque line, but smaller than 1.9 times said width, preferably 1.5 times to 1.8 times the width of the opaque line. The two screens, further, are positioned symmetrically in relation to each other so that a central opaque line of one of the screens symmetrically overlaps a central transparent interstice of the other screen.

Abstract: A sight means, particularly for weapons and other objects which are intended to be sighted onto a given point, comprises two mutually spaced and two mutually parallel grid discs (3,4) each of which includes a transparent disc provided with concentrically lying opaque grid lines separated by transparent interspaces, and which grid discs (3,4) are arranged in a tubular housing (2). In accordance with the invention a central region (7,8) is devoid of opaque lines in the center of the discs (3,4) this region having a size of approximately 1/5 to 1/2 of the disc diameter, or a corresponding measurement, the target being intended to be viewed through the aforesaid regions.In accordance with one embodiment one (3;4) of the grid discs has solely one more opaque line than the other (4;3) of the grid disc in the region provided with grid lines.