Photon pulse
From Memory Alpha, the free Star Trek reference
A photon pulse was a type of starship-mounted weapon or weapon modification.
The shuttlecraft Magellan fired photon pulses from its type-4 phaser emitters, into the pocket of null space, to chart the anomalies perimeter. (TNG: "The Outcast")
Entharan starship was equipped with photon pulses. When Kovin fired a spread of photon pulses, from the bow of his ship, at the USS Voyager. In the opening volley, the pulses lowered Voyager's deflector shield strength down to 82%, and by the time his assault was complete, he had completely disabled Voyager's shields.
His ship was ultimately destroyed after he had shunted all the power to his ship's photonic emitters, while attempting to fire on Voyager. (VOY: "Retrospect")
Unlike the Starfleet photon pulses, Entharan pulses were depicted as bolts of energy. It is unclear if the photonic emitter is related to the photon pulses, or if the reference was intended to be associated with the photonic pulse. The dialog seems to support the former, while the naming seems to support the latter.
