The high magnification sight is normally equipped with a graticule (or reticule). The graticule, which overlays the field of view, is a pattern of marks which can be used for alignment and gunnery purposes.
For each particular set of conditions (such as charge temperature, air pressure and target speed) a different set of graticule markings would be required, but such an approach is impractical since it would clutter the field of view and render the sight unusable. Therefore, most graticules define the correct gun position for a number of target ranges, but they are only accurate for one particular set of circumstances.
Conventional graticules are etched on to glass and either positioned in the optical path or injected via a half-silvered mirror. If too much information is included on the graticule, the operator's field of view can become cluttered. To overcome this problem, it is possible to have graticules which can be switched in and out or partially masked, although great care must be taken to maintain alignment accuracy. As an alternative, graticules may be generated electronically and these can easily be switched off or masked when not required. As both etched and electronic graticules physically exist, they can provide a reflector for the radiation from a laser sensor damage weapon. In the future, therefore, it is likely that sight graticules will be generated by holograms, which present no reflector for laser light.
Sergyi Way
09.01.2007