Red dot

The view through an Red Dot.

Red dot sight is a common classification[1] for a type of non-magnifying reflector (or reflex) sight for firearms that gives the user an aimpoint in the form of a red dot. A standard design uses a red light-emitting dioade (LED) at the focus of collimating optics which generates a dot style illuminated reticle that stays in alignment with the weapon the sight is attached to regardless of eye position (parallax free). They are considered to be fast acquisition and easy to use gun sights for target shooting, hunting, and in police and military applications.