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Since their introduction by G. Gr\"atzer and E. Knapp in 2007, more than fourdozen papers have been devoted to finite slim planar semimodular lattices (inshort, SPS lattices or slim semimodular lattices) and to some related fields.In addition to distributivity, there have been seven known properties of thecongruence lattices of these lattices. The first two properties were proved byG. Gr\"atzer, the next four by the present author, while the seventh was provedjointly by G. Gr\"atzer and the present author. Five out of the sevenproperties were found and proved by using lamps, which are lattice theoretictools introduced by the present author in a 2021 paper. Here, using lamps, wepresent infinitely many new properties. Lamps also allow us to strengthen theseventh previously known property, and they lead to an algorithm of exponentialtime to decide whether a finite distributive lattice can be represented as thecongruence lattice of an SPS lattice. Some new properties of lamps are alsogiven.

Notes on congruence lattices and lamps of slim semimodular lattices