Abstract: A multilayer laminated body has a determinate system of hollow passages and is formed by an assembly of flat layers of polymeric materials having major dimensions in orthogonal X and Y directions and a thickness dimension in a Z direction perpendicular to the X and Y directions. Selected ones of the layers have openings extending through in the Z direction, and other layers have canals formed in an X-Y plane. The openings and canals form parts of hollow passages so that assembly of multiple layers joins openings and canals forms complete and continuous passages through the assembled layers. Layers joined in pre-laminate assemblies are assembled together in precise relative positions for desired alignment of the canals and openings. The passages can be filled with optically conductive material or electrically conductive material and electrodes can be appropriately positioned for acting on fluids passing through the body.