Deflector shield

The Enterprise deflector shields take a hit from the Klingons.

The deflector shields (or more commonly referred to simply as shields) are an electromagnetic force field that can be projected around a starship, starbase, or planet by technological means and act as the first form of defense against enemies or natural hazards, using deflection to protect said body from various forms of radiation and matter collisions.

Description

Most starships are fitted with deflector shields, often projected from a deflector dish, to protect them from particle impacts which, particularly at high velocities, could cause huge amounts of damage. While basic deflectors and deflector beams could provide minimal protection from weapons fire and basic mishaps, the majority of advanced starships were also fitted with more powerful shielding which could be activated in tactical situations. However, these shields were sufficiently powerful that they also blocked out transporter beams. (TNG movie: Star Trek: First Contact, et al.)

Shields could be configured in two forms; ellipsoid form shielding, common in Federation starships in the 24th century, which projected a shield bubble around a starship. Or contour-conforming shielding which was projected much closer to the ships hull providing more specifically localised protection. Some shielding systems also allowed shielding over specific areas of a ship to be activated or deactivated to provide protection for a specific area only and presumably reduce power consumption not protecting the entire hull. (TNG movie: Star Trek: First Contact, et al.)

Horta were seemingly invulnerable to even very powerful shields, being capable of passing straight through them with very little effort. (DS9 novel: Devil in the Sky)

While conducting operations in the Badlands in the early 2370s, the Maquis discovered a way to apply regenerative tuning techniques in order to keep their shields operative in the extreme magnetic and radiation flux of the region. In early 2372, the USS Enterprise-E applied some of these techniques to their shields while inside the Pantera Nebula. (TNG eBook: A Sea of Troubles)

In addition to standard deflectors, there a number of other shielding technologies that were developed including:

• Regenerative shields, used by the Borg, which analyze weapons fire and adjust shield frequencies to better resist oustide forces. Other races have subsequently adopted this technology, but presumably have had less success than the Borg, not having the Collective's processing power to analyze incoming weapons fire. (TNG episode: "The Best of Both Worlds", et al.)
• Metaphasic shields, developed by the Ferengi Dr. Reyga, are capable of withstanding the pressure, radiation and energy of a star's corona. (TNG episode: "Suspicions")
• Multi-adaptive shielding, developed by Erin and Magnus Hansen, was a shielding system specifically designed and used to mask a vessel from Borg sensors. (VOY episode: "Dark Frontier")

Frequencies

257.4 was the shield frequency of the USS Enterprise-D in 2371. The Klingon Duras sisters had previously captured Geordi La Forge and while under their captivity had Tolian Soran (a scientist they were working with) modify La Forge's VISOR to transmit a video stream to them. When Geordi returned to the ship, the sisters were able to expose the frequency and fire through the Enterprise's shield. (TNG movie & novelization: Generations)

Earth and Federation shields

By the 22nd century, humans had only developed basic deflector dish technology, which allowed them to operate more safely at warp speeds, but had to resort to polarized hull plating in tactical situations. Many species in the Alpha and Beta Quadrants had developed more advanced shielding technology by the 2150s, these included the Andorians and the Klingons. (ENT episodes: "Sleeping Dogs", "Proving Ground")

Earth and Federation shield types

FSB-type

Scorpio-class class II corvette

FSD-type

Makin-class mark II class VII assault ship • Continent-class class IX assault ship

FSL-type

Andor-class mark II class IX cruiser

FSS-type

Excelsior-class class XIII-XIV battleship

Klingon shield types

KSC-type

T-3 D'aka-class class VI assault ship

KSG-type

T-5B Mas To Gal-class class VII assault ship

KSH-type

L-13A K'el Ri'anda-class class IX battleship

KSJ-type

T-5A Mas To Gal-class class VII assault ship

KSL-type

L-13C K'el Ri'anda-class class X battleship

KSN-type

T-12 Na Ra'den-class class IX assault ship

KSP-type

L-13D K'el Ri'anda-class class XI battleship

Appendices

Connections

• polarized hull plating
• ablative armor

External links

• Deflector shield article at Memory Alpha, the wiki for canon Star Trek.