The quantum field focus controller was a piece of technology aboard Vesta-class that allowed the starship to keep shields and communication online and at 100% during slipstream travel.

It could also be used as a beam intensifier. If the ship is heavily damaged and the field focuser is still online, power from the phasers and shields could be rerouted to the main deflection system and be used to ether create a shield bubble or a high intensity phaser beam which could be sustained for as long as power can be routed to the deflector array.