A method of producing a transistor includes providing a substrate including in order a first electrically conductive material layer and a second electrically conductive material layer. The cone portion has a first position concealing the at least two fingers and a second, extended position exposing the at least two fingers. At each combination of input parameters, the system is driven to a \u201cquasi-steady\u201d state, rather than waiting for it to reach a steady state. This system and method also corrects the display system by providing an arrangement that employs a minimum of required changes so as to avoid any changes that can consequently affect the output image of the display system. The devices can be used in vascular channels, urinary tracts, biliary ducts and the like, and filter emboli and other debris generated at a treatment site.