The fan-favourite RPG Star Wars: Knights of the Old Republic was the first to introduce a device known as a stealth field generator - a small and portable cloaking device that can be worn as a belt. There doesn't appear to be much mention of these devices outside of the Old Republic era (the only two exceptions mentioned being Star Wars: Battlefront II (from 2008) and Star Wars: Jedi Knight: Jedi Academy).
Why is that?
I understand that these devices have their limits (such as requiring the user to move slowly to remain cloaked, and it would take a particularly skilled user to be able to remain cloaked while running), but it still seems like these devices (or similar devices) would have been useful to the numerous factions in Star Wars (Rebels, the Empire, Sith, etc.) But, not only do these devices not appear in the original or prequel trilogies, they're not even mentioned, with the exception of the type of cloaking devices made for starships. They probably would have been particularly useful to the Rebel ground forces during the Battle of Endor.
It's also worth noting that you can obtain one of these devices in the opening chapter of the first KOTOR (if you spent any points on stealth when creating your character), which would seem to suggest that these probably aren't too difficult to obtain.
Did the technology somehow become lost between the events of the Jedi Civil War and the Clone Wars? Did it become obsolete somehow?