What are the parameters in ALFA

I use ALFA that is Plug Ins of Rhino.
https://www.solemma.com/alfa

I don’t know what the parameters indicate when I assign materials by layer.
For example, R(photopic) and R(melanopic) of opaque materials, and Rf(pho), Rb(mel), Rb(pho), Rb(mel), T(pho) and T(mel).