From Halopedia, the Halo wiki
A telescopic sight, commonly called a scope, is a device attached to a weapon used to give additional accuracy using a point of aim for weapons such as firearms, airguns and crossbows. Other sighting systems are iron sights and laser sights.
The UNSC uses a scope on a wide variety of its weapons, ranging from its sniper rifle variants, to its battle rifles, and even its handguns, though the handguns employ a "smart-linked" camera. All of these scopes and cameras can transmit their feeds to UNSC soldiers' heads-up displays via smart-linking. The Covenant also use scopes (e.g.; the Covenant Carbine and Type-50 particle beam rifle), though the mechanics of their equipment are unknown.
There are a wide variety of scopes, each differing in type, function, and purpose. For example; the standard scope of an S2 AM Sniper Rifle is capable of 5×/10×, 2×/8× or 2×/10× magnification for long range combat, and are electronically operated. The S2 AM Scope also includes a night vision function in some models for night combat. The scopes on the BR55 and BR55HB SR, however, are only capable of 2× magnification, intended only for short to medium-range accuracy, using focusing lenses for magnification. The M41 Rocket Launcher and the fuel rod gun both have 2× scopes, as well, to better pinpoint targets and to extend their effective range.
Known telescopic sights
List of appearances