Photon pulse

A photon pulse was a type of starship-mounted directed-energy weapon used by the Entharans and Starfleet.

In 2368, Commander William Riker and the J'naii scientist Soren used a series of photon pulses fired from two type 4 phasers, with which their shuttlecraft had been fitted, to chart the outline of a null space pocket into which a J'naii shuttle had disappeared. They were able to obtain a map the perimeter of the pocket by charting where each pulse disappeared into the null space. 

In 2374, an 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 Voyagers deflector shield strength down to 82%, and by the time his assault was complete, he had completely disabled Voyagers 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. 

Also see

 * Antiphoton pulse