The chrono deflector was a time travel-device invented by a Klingon scientist named Korath in the early-25th century. The device operated by generating a powerful tachyon pulse to form a temporal rift, which could then be directed to a specific time and place. Although able to generate a stable rift, the device also produced a large amount of tachyokinetic energy as a byproduct of its operation, posing the risk that it would burn itself out after a single use, prohibiting a return trip for the user. (VOY episode: "Endgame")
In 2404, Admiral Kathryn Janeway made a deal with Korath to secure him a seat on the Klingon High Council in exchange for use of the chrono deflector. But when Korath demanded an ablative generator in addition, Janeway was forced to steal the deflector. With the help of Harry Kim, Janeway installed the deflector on her shuttlecraft and used it to travel to the Delta Quadrant, the year 2377. Encountering Voyager, she instructed her counterpart to emit an antitachyon pulse towards the rift to seal it, to prevent Korath from pursuing her back in time. Admiral Janeway subsequently collaborated with the Voyager crew to change history and return the ship to the Alpha Quadrant seventeen years before it would have without her intervention. (VOY episode: "Endgame")
The idea for the chrono deflector first came to Korath at a meeting of temporal scientists in 2382 when he realized transporter beams were similar to deflector rays. (DTI novel: Watching the Clock)
- The chrono deflector prop used in "Endgame" was used in the Enterprise episode "Precious Cargo" as a power regulator for the stasis pod.