If one consciously asked her this question, they might get a response something like...
[Alicia Thorn's]* Prismatic Focus...
... Readily brings Light into the world.
... Is connected to [Alicia Thorn's] Lantern.
... Amplifies Light channelled through it.
... <A complicated intuitive grasp of the White Light constantly rebirthing itself as a metaphor for how to actually anchor a secondary reservoir to this device goes here.>
... Births the colors of the Emotional Spectrum from the White Light as needed.
... Anchors the other Lights to their associated reservoirs as well.
... Is hers, and no-one else's, until she can use it no longer. (Hers to loan, perhaps, but also hers to repossess.)
* Here read to mean Wildcard, actually.
Of course, no-one is consciously asking her this, and this is hardly actually an act of her signature magic (all credit for the idea to the works of Doctor Jenna Katerin Moran) anyway, she wouldn't expect to get more than the top three lines here without actually Doing It Properly, but it's still a decent guideline.