A method and system for designing and implementing a finite impulse response filter to create a plurality of output signals, each output signal having the same frequency but at a different phase shift from the other output, is described. The filter element collapses into the outer end of a catheter for deployment and retrieval through a vascular system of a patient. The oxidation solution can include one or more of: water, ozone, hydrogen chloride, sulfuric acid, or hydrogen peroxide. The change in states in the latter case results in a change in electrical conductivity. If the buy-out provision condition is satisfied, the seller retakes the product from the original purchaser and resells the product to a subsequent purchaser. In preferred embodiments, a direct write process, such as ebeam lithography, is used to define defects and functional elements, such as waveguides and cavities.