A sight or sighting device is any device used to assist in precise visual alignment (i.e. aiming) of weapons, surveying instruments, aircraft equipment, optical illumination equipment or larger optical instruments with the intended target. Sights can be a simple set or system of physical markers that serve as visual references for directly aligning the user's line of sight with the target (such as iron sights on firearms), or optical instruments that provide an optically enhanced—often magnified—target image aligned in the same focus with an aiming point (e.g. telescopic, reflector and holographic sights). There are also sights that actively project an illuminated point of aim (a.k.a. "hot spot") onto the target itself so it can be observed by anyone with a direct view, such as laser sights and infrared illuminators on some night vision devices, as well as augmented or even virtual reality-enabled digital cameras ("smart scopes") with software algorithms that produce digitally enhanced target images.
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Gun sight in the context of Nuclear technology
Nuclear technology is technology that involves the nuclear reactions of atomic nuclei. Among the notable nuclear technologies are nuclear reactors, nuclear medicine and nuclear weapons. It is also used, among other things, in smoke detectors and gun sights.
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