Brilliant viewfinder

摘要

The viewfinder superimposes the collimated image of symbols at infinity on a direct view of the landscape. A concave spherical mirror 2 collimates at infinity the projected image of a symbol determined by an object 11 placed in the focal plane. The optical path is bent by a semitransparent plate 3 placed between the object 11 and the mirror 2. The mirror 2 and the plate 3 allow light from the landscape to pass through to the viewer's eyes placed behind the plate 3. Application to gun firing on helicopters. <IMAGE>