Optical switching device for a transparent node of high switching degree adapted to spectral equalization

i i i i i i i i A device (D) dedicated to optical switching in a switching node (NC) comprises at least one first switching matrix (MC) and one second switching matrix (MC) coupled to each other and each comprising i) a first stage including Ndiffusion modules each having a first input and Mfirst outputs and ii) a second stage including Nfusion modules each having Nsecond inputs each coupled to one of the Mfirst outputs of one of the Ndiffusion modules via an optical line, at least one third input and one second output. The second stage of at least one of the matrices comprises at least one additional fusion module having Nsecond inputs adapted to apply optical power adjustment and one second output. At least one optical line (LS) couples the second output of an additional fusion module of one of the matrices (MC) to a third input of each of the Nfusion modules of the other matrix (MC).