UV, or UltraViolet lightsabers are often considered the pinnacle in lightsaber craft. Boasting a nearly invisible and scorching hot blade, UV sabers can be as much a liability to the user as it is to his enemy.
In order to build a UV saber, you have to have a purple synth crystal, or natural white or purple stone(quite rare). A regular adegan won't do, as it needs to be an exotic one to handle the higher power output. The blade will need at least 2 novae for tuning purposes. It also will need a really good power cell as the shorter wavelength needs more power to activate, so the life of the battery would be much shorter than an average saber. Even with the exceptional power cell, the battery life of the saber would be about half that of a normal saber. Also, the amount of power and the focus would cause the almost invisible blade to run very very hot, possibly hot enough to cut through Phrik. It is 'almost invisible' because the way heat distorts light to the eye. In this way, a person would see the heat waves, and an almost violet tinge where the saber is scorching dust in the air when activated.
Requirements
Only a Jedi of the rank of Dark Jedi Master or higher may attempt to construct, let alone wield an ultraviolet saber.