Pattern buffer, Shattered mirror

The pattern buffer aboard the USS Defiant

The pattern buffer, also known as a transport or transporter buffer, was a key component of transporter systems. The buffer was used during matter-energy conversion to temporarily store the matter stream following dematerialization, but prior to sending the stream to its target. This was done because of the relative motion of transporter and target. By temporarily storing the matter stream, the Doppler compensators had enough time to adjust the targeting scanners.

A matter stream could not be stored indefinitely in the buffer; after 420 seconds(citation needededit), the stored pattern would degrade and the object was lost. The only known occurrence of a person surviving in a buffer longer than the theoretical maximum was Captain Montgomery Scott on board the USS Jenolan. Following the Jenolan's crash landing on a Dyson sphere, Scott, with the help of Matt Franklin, was able to store his pattern in the buffer for 75 years. This was achieved by disabling the rematerialization subroutine, connecting the phase inducers to the emitter array, bypassing the override, and locking the buffer into a continuous diagnostic cycle. Although Captain Scott's pattern suffered less than 0.003% degradation, and was successfully recovered by Geordi La Forge of the USS Enterprise-D in 2369, Franklin was irretrievable, as one of the inducers had failed, causing a 53% degradation in his pattern. (TNG: "Relics")

In 2152, diamagnetic storms saturated with polaric energy were encountered on a planet visited by the crew of the starship Enterprise. The storms interfered with the operation of the ship's transporter, resulting in Hoshi Sato being trapped in its pattern buffer for 8.3 seconds while Malcolm Reed worked to reintegrate the matter stream. (ENT: "Vanishing Point")

A pattern buffer malfunctioning was the leading cause of transporter accidents. In the 2270s, during the V'ger incident, Commander Will Decker and Lieutenant Cleary did repairs on the pattern buffer but it malfunctioned while Cleary was replacing the transporter sensor. Janice Rand attempted to beam Commander Sonak and a female officer aboard the Enterprise but they were both killed. Scotty later repaired the pattern buffer and the sensor in time to beam Ilia and Leonard McCoy aboard. (Star Trek: The Motion Picture)

On Galaxy-class starships, the pattern buffer was located immediately beneath the transporter pad. (TNG: "Realm of Fear", "Attached")

When weapons were beamed to a rebel camp on Krios from a cargo transporter of the Enterprise-D in 2367, Miles O'Brien asked Geordi La Forge if he could check the reliability of the pattern buffers. (TNG: "The Mind's Eye")

When Jadzia Dax decided to stay on Meridian in 2371, the transporter buffer of the USS Defiant was used to bring her quantum matrix in sync with that of the Meridians. (DS9: "Meridian")

When the Orion Syndicate planted a bomb on board the USS Rio Grande, Odo was able to mitigate the damage from the bomb by beaming it out and channeling the explosion through the transporter buffer. (DS9: "The Ascent")

Starships could also transfer patterns from one pattern buffer to another by "locking on" to the target buffer and energizing. (VOY: "Future's End, Part II")

To eliminate the medical condition called transporter psychosis, Federation transporters were equipped with multiplex pattern buffers. (TNG: "Realm of Fear")

The transporter buffer of an Intrepid-class starship performed a version of a microcellular scan every time it was used. (VOY: "Favorite Son")

Cardassian transporter systems were still equipped with active feed pattern buffers in 2367; these were considered outdated by Starfleet. (TNG: "The Wounded")

In 2374, the crew of Voyager overloaded the ship's pattern buffers attempting to transport deuterium from beneath the surface of a Y-class planet. (VOY: "Demon")