Shield generators produce the power needed to create and maintain deflector shields, then focus those shields around a given object, be it a ship, building, or even parts of an entire planet. There are two types of deflector shields: ray shielding and particle shielding.

Most starships carry some form of shielding technology, to protect it not only from the natural hazards of space travel, but also enemy attacks. Since smaller ships have limited power with which to generate deflector shields, they often only protect set areas, or arcs, of the vessel and rely on maneuverability to avoid fire.

Ground-based installations use immense projectors to generate a deflector shield, like the one that protected the Rebel base on Hoth from orbital bombardment. This shield worked in both directions, however, and had to be lowered momentarily to allow the launching of evacuation ships. During the Battle of Hoth, Imperial ground craft landed beyond the shield perimeter, and marched over land to destroy the generators powering the shield.

A huge generator complex with a parabolic emitter dish projected a defensive shield around the second Death Star. The generator was located on the surface of Endor's moon, enveloping the Death Star high above in protective energy. A Rebel strike team managed to knock out the shield generator in time for Alliance starfighters to fly into the Death Star's superstructure and destroy the station.

Alien cultures have developed their own native analogs of deflector shield technology. The Gungans of Naboo adapted their energy bubble containment technology to form a protective umbrella over their Grand Army. Huge reptilian fambaa creatures carry the emitter and projector drums on their backs. The shield can deflect laser and artillery fire, but can be permeated by objects with less kinetic energy, such as battle droids on foot.