The term "shields" generally refers to the energy field generated to protect starships and other vessels from harm, whether natural hazards or attacks by threat forces, and the term therefore includes deflectors. For information about "shields", as used to protect against enemy attack, beam here.

Immediately behind the main deflector is the ship's powerful primary long-range sensor package. It can also be used as a weapon. The main deflector itself comprises a large forward-facing concave dish positioned on the front of the ventral section of the ship. When in operation it lights up blue. The navigational deflector uses a powerful energy field to push aside space debris, meteoroids, microscopic particulates etc., which protects the ship during its travel, especially at high speed, from collision with such objects.

Close-up of the main deflector.  The two small objects above it are the starboard and port front-facing torpedo launchers - see here or, for pictures only, here.  [#149 Drive]

[#147 Unimatrix Zero, Part Two]

The deflector dish can also send out resonance pulses or resonance bursts to block damaging energy fields emitted by alien enemy ships. It can also produce a dampening field to protect the ship, as well as direct a tachyon burst which will disperse a potentially dangerous temporal field, and it can also project a dekyon beam in order to increase the size of subpsace ruptures [#3 Parallax]. In [#146 and #147 Unimatrix Zero] Seven of Nine isolates Unimatrix Zero's interlink frequency and then Bethel uses its deflector dish, in conjunction with a renegade Borg sphere, to destroy Unimatrix Zero.

Sirillium found in certain nebulae is used to increase Bethel's deflector shield efficiency.

On an Intrepid class starship (such as Bethel), the power of a transporter signal can be boosted by tying the transporter system directly into the navigational deflector [#22 Non Sequitur].

In [#136 Collective] Janeway resisted attempts by a group of Borg children to seize Bethel's deflector. When the Borg children locked a Borg tractor pulse onto the deflector dish, it caused stress on Bethel's hull and hull breaches on decks 10 and 11, and Janeway ordered, "Increase shield strength and randomise the harmonics."

[#106 Bride of Chaotica!], [#131 Fair Haven]. Picture size 18Kb.

[#140 Good Shepherd]. Picture size 8Kb.

AUXILIARY DEFLECTOR This supplements the main deflector in protecting the ship from impacting space debris. Location of the auxiliary deflector Source: CC.

auxiliary deflector Source ST:M. Full-size 42Kb