A simple triangular box for displaying 150mm square lithophanes that are no more than 4mm thick on the edges. There is a depression in the center of the base for a tap light from the Dollar Tree. The light is approximiately 69mm in diameter. (seriously, I didn't make that up.)

Once printed, the phanes should just slide down into the slots. Turn on the light, and then settle the top on.

UPDATE v2 of the base added. Now with cable port for wired electronics.