A light-splitting device includes a power module, a transmission module and a filter module. Three or more equally spaced rods are provided for guiding the slider, and are arranged to define the vertices of a regular polygon with the center of application of the stem or the center of gravity of the slider, to prevent any torque or rotation moment from building up on the slider as it slides on the rods. A second etching treatment is carried out to the substrate to form a trench region at the base trench so that the trench region has a rounded-off upper edge. A patterned seed metal layer is on the metallization in the window and on the second inorganic layer around the window. The elastomeric sealant coatings provide corrosion protection over the seams and maintain a crack-free surface over a broad temperature range. Also, a coupling, a ledger and a standard intended for such a scaffolding system are disclosed.