Stimulation and perception of transparency

Summary After a brief exposition of the algebraic theory of transparency and of the various experimental predictions deduced from it, the theory is reconsidered with reference to the paradigmatic case of transparency obtained using an episcotister. The first result of this analysis is that the same local stimulation, described by the same equation, gives rise either to color fusion or to color scission, that is, to transparency. Therefore, the assertion that the same equations (Talbot's law) describe both the color fusion and transparency is not a hypothesis but the ascertaining of a fact. Another important result is that the two parameters of transparency, the coefficient of transparency and the measure of the color t of the transparent layer, correspond to the empty sector of the episcotister and to the color of the episcotister, respectively, both being therefore physical measures.